Hi Ted, First off I'm no mathematician but you might be forgetting about the angle change when zeroing, At the lower velocity you tilt the barrel higher to compensate for the distance to zero (50yds) if the velocity increases that angle changes to hit the 50 yds zero. I put your data into the Hornady calculator, here's what it says. 1000fps, BC 0.09, 26gn projectile, scope 3.75" above the bore, 0yds= -3.8", 25yds = -0.6", 50yds = 0", 75yds =-2" 100yds =-6.9". 1100fps, BC 0.18, 26gn projectile, scope 3.75" above the bore, 0yds= -3.8", 25yds = -0.9", 50yds = 0", 75yds = -1.2" 100yds = -4.5". 1100fps, BC 0.09, 26gn projectile, scope 3.75" above the bore, 0yds= -3.8", 25yds = -0.8", 50yds = 0" , 75yds = -1.5", 100yds = -5.5. I read somewhere that the location of the scopes reticle adjustment relative to the triangle created by the barrel and scope axis relative to the projectile start point will make a difference in the amount of clicks needed to reach zero (ATN web site I think), your rifle has the projectile a long way behind the scope reticle adjustments, in other words your adjustments are having a greater effect than if the projectile was below them
First of all, I want to say I am so happy to see new content on this channel. Ted is a top-notch marksman and I have enjoyed these videos for years. Regarding the BC - why not put another chronograph at 100 yards and measure that velocity compared to muzzle velocity and calculate BC that way.
@@TedsHoldOver teddy you have done so much for us you have a patron or donation area? Shit I’d buy your only fans if you do weekly Airguns hunts on it😂
Thank you for the vid; it is quite stimulating --- which makes you the elite provocateur of thoughts, avvocato del diavolo, and rouser of enquiry into the logical/illogical world of Ballistics. This video shows that despite efforts to make sense of logistics with the behaviour of missiles, all pre-conception seems futile. You, sir, have dared to be the Sherlock Holmes of your vocation. "The only thing that remains constant is change," attributed to the Greek philosopher Heraclitus, seems to ring true in your efforts. To reiterate Mr. Holmes, "When one eliminates the impossible, whatever remains, however impossible, must be the truth". Thank you again your efforts. Stay well.
I believe you found the perfect speed and twist rate for that specific lenght and weight over that specific distance. In other words, the slug flies true through the trajectory curve for perfect aerodynamic angle of attack. No nose up or down during the flight through the trajectory curve. Just perfect. The choke of the barrel will also play a big role here on how it releases that slug (angle of attack). It's like finding a needle in a haystack, possible but very rare. Good football quarterbacks have the ability to throw, release and spin the football just right to achieve perfect angle of attack, speed and twist for optimal flight in order to achieve maximum distance with the least effort. Everyone who has thrown a football enough has at some point found that "feeling" of a perfect release. This is very difficult to achieve with a barrel in a gun. I believe you have found your unicorn.
@@Oregon-airguns agree, what Rolfe is saying is kind of right but does not explain Ted results. That’s simply down to incorrect data and operator error!
The inability to find the perfect ammo for YOUR gun is what makes these air guns nothing but cash cows for the manufacturers. You are all chasing the wind! Ted got lucky....after admittingly spending OVER 1K on ammo. REDICULOUS.
As an old high power rifle competitor, 200 to 600yds and 1000 yards. I am enjoying seeing you go thru the exact same testing to achieve the best accuracy you can from your equipment in an air rifle. Your finding that a pellet dia. in ten thousands of an inch can make such a huge difference in performance. My shooting was 50 years ago, and I heard of some top shooters that would go to the sierra factory and mic bullets coming out of the bullet making machine until the die wore down enough to get the dia they wanted and then take the next ten or twenty thousand bullets for reloading because that dia is what their barrel liked.
@@tadracket448 let me give you some advise. Steeer clear of fx… take a look at the Vulcan 3. It’s a straight killer right out of the box. Shooting avs slugs. M channels not nearly good as teds. But I’ve been down the fx road and it was a total nightmare.
Hi Ted. I just tested this with my LabRadar. I used the same barrel, 800mm 1:14 twist and same slugs, NSA 31.2gr .2165 . I shot a 15 shot string at 100yd. Average muzzle velocity was 1,087 and average velocity at 100yds was 941. Taking air temperature, station pressure, and humidity into account I got a G1 BC of .132. RA4 BC was .104.
Ted for me this has just blown my mind your dedication to education of the masses is incredible, thank you . Keep doing all that you do especially nailing the pigeons.
I've also ran into many ballistic "mysteries" but in the end they were simply not taking into account of atmosphere conditions or user error. Temperature and altitude density have HUGE affect on BC/trajectory. Zero one day and not readjust to new weather condition into the ballistic calculation will through you off big time. I've learned the hard way and always validate zero and reset atmosphere conditions in ballistic solver with minimum local weather station information, I try use a weather meter for my ballistic solver and make a point to update the information EVERY HOUR! Ted: Love your show and learned a ton from you especially on tuning the gun. Keep up the great work!
More Spin, Less Drag In this article, we look at how twist rate and stability affect the Ballistic Coefficient (BC) of a bullet. Again, this topic is covered in detail in the Modern Advancements book. Through our testing, we’ve learned that adequate spin-stabilization is important to achieving the best BC (and lowest drag). In other words, if you don’t spin your bullets fast enough (with sufficient twist rate), the BC of your bullets may be less than optimal. That means, in practical terms, that your bullets drop more quickly and deflect more in the wind (other factors being equal). Spin your bullets faster, and you can optimize your BC for best performance. I think what you're seeing is your finding the sweet spot of the spin rate, ,this increased the BC which effectively increased the accuracy for longer ranges. I would almost guess the bullet as two sweet spots one low at the smaller BC and the one you have found...
I agree: it would make sense that a higher initial velocity, and greater rate of spin, would ccause more "lift" from spin "traction" as the bullet bites it's way thru the air. I love this stuff, as I've been an avid handloader for years, and the mysteries keep coming! "What we THINK we know, vs What we find in testing"
@@mikecollins8241 You, sir, are a THINKING man in the best sense. I have echoed your statements for the many years of searching for truth in all things in this world. Thank you for your maxim. Stay well.
The inability to find the perfect ammo for YOUR gun is what makes these air guns nothing but cash cows for the manufacturers. You are all chasing the wind! Ted got lucky....after admittingly spending OVER 1K on ammo. REDICULOUS.
So what about the drag increase in transonic region? At 1100 fps(about mach 0.97 drag on projectile at the muzzle is so much higher than subsonic speeds and its nothing to with spin rate or even type of the projectile (bullet,slug, airplane!....)what you saying could be true in supersonic projectiles like canterfire rifle bullets,but here we are dealing with subsonic airgun projectiles, clearly something is going on in this case,but as ted says, it must be impossible!!
Wonderful video, I've been playing with the neilsen slugs in 21 and 23 grain in my Avenger, I upped my reg pressure about 150 psi to 2250, and I noticed a drastic difference in the amount of drop beyond 75 yards..much more so than I'd expected. Now I'm enjoying some flatter shooting, but I've yet to push them across the chrony..that's the next step 😏 thanks for another great video, appreciate your dedication to the airgun community and sharing what you learn.
I really enjoy listening to ballistics nerds (like you and Matt) heading into the weeds of researching and explaining what's going on with slugs & pellets in flight. I'm not sure what percentage I'm missing, but it's fascinating watching you work on it.
You're going to LOVE that wildcat. I grab my WC a lot more than my impact or any other rifle. It's just the perfect balance of comfort/accuracy/power. If someone were to ask what their first FX should be, I would recommend the Wildcat BT, hands down.
Internal ballistics are a funny thing. Barrel whip can throw the same bullet to two sweet spots at different velocities. The first (lower velocity) shot may be whipping the muzzle down slightly and giving you a stable muzzle exit at with the muzzle low. The higher velocity may be throwing your groups higher. This gives you a different number to calculate BC than the 'accurate' number. You'd have to check velocity at multiple points on the trajectory and see if the velocity is dropping with the BC. The other alternative is that the BC is changing due to transonic interactions with your bullet profile. Bullets do weird things whey they try to push air around them at supersonic speeds, even though the bullet itself isn't supersonic. You could be getting a better BC because of the supersonic flow characteristics of this particular profile. Me, I avoid transonic as much as I can. With my .44 Magnum rifle loads, I stay at about 1,050 FPS. Bullets that fly much faster risk running into weird stuff, as you may have experienced. Only strike against this theory with your bullets is that they slow down REALLY quick to full subsonic flow.
yeah, you missed the point - he measured the difference with the same velocity 1100 at 100 and 50 and compared the difference. Pay attention, focus and don't speculate
Great video Ted ! I’ve watched you from the start , and you got me with you never ending quest for top performance. With the right equipment, and understanding the science the hours you spend on target make it all come together .thanks for sharing your system and how it works ! I’m still amazed at shooting nickels at that distance………with air…….. !
Good god! Your still the goat! I was like 👍 2k btw. I’ve noticed the same thing with different lots of 22lr some lots come out to .170 bc and others .123 same exact bullet, even weighed them. Billets we’re Norma Tac they vary in velocity a lot from lot to lot. Some lots 950 others 1100. Thx again Ted!
I remember when I was a kid, my grandpa would talk to me about a “magic velocity” for his .22 cal while I sucked feverishly on a werthers original. He was a professor in physics and told me some jibberish about how at a certain velocity and twist rate, outward forces such as the effect of wind and even RAIN would have little to no effect. Those numbers I suppose, would apply to slugs from an air gun as well. Matter of fact, I know they do “;) Dam, those Werther originals are good…
Hi Ted, What you are observing is the effect the speed and hollow point has on the BC. Higher the velocity of the projectile = higher BC and the hollow point traps air (bubble) and the higher the pressure the harder the bubble is and the more it's aerodynamically shaped which results in reduced drag and higher BC. Mythbusters "golfball effect" and "tailgate" has very nice visualization of the phenomena.
Hi Ted, great info on the airgun and new slugs. That is pretty cool what you are getting with these slugs! I had one thought which is - why introduce the scope change into your calculation? Simply shoot at 50 yards and it impacts the target, you can make it near zero but quite honestly it does not destroy the point of aim if it hits a few inches low. Then simply back the target up, continue to shoot at the same aiming point. Measure the difference between the two groups and you have the drop at 100 yards. The aiming point is quite irrelevant so long as the aiming point is the same each distance, I actually prefer to make a cross with a heavy marker or even tape depending on what I am doing. That way no scope calibration issues are introduced, etc. The drop is what the drop is. Just have to shoot at the same point, leave the scope alone. Keep on killing those starlings!
Hi Ted. You're the man broseph. Come on out to new Hampshire and we'll rip up some grey squirrels. I love all your videos I love how you get in depth and explain all the math in a way that's made simple. Keep up all your good work and keep up all the videos Ted. You are the balls and I always look forward to your next video. Let me know if you are ever in New England we can tear it up
Good to see you back Ted!! On the BC is it possible that the hollow point is creating a slip stream affect like a pickup truck box does with the tailgate closed air moves freely over the truck. With the slug the cup fills with air that is compressed whether going fast or slow causing the slug to stabilize.
BC is defined by change in velocity between 50 and 100 yards. Delta in POI could be deceptive because it includes the effect of barrel harmonics. Summary of insightful statement by RyeOnHam
nope, what he wrote was dumb because he doesn't pay attention and makes up crap that sounds smart to other people that don't understand basic math and don't pay attention. Barrel whip is not a variable because he was shooting at the same speed at 100 and 50 yards. The barrel harmonics doesn't change because of the distance you shoot or because you aim at different thing....
Ive watched you since the edgun matador days. The 130 yard pigeon shot got me into the air world. Ive got an impact m3 .30 cal shooting knockouts 900-905 sub moa out to 150. Jsb pellets 50.15 gr also mostly moa to 150 with some flyer. Stx standard barrel @910-915. Wish I could post pics here. Great to see the content again
I wonder if the air hitting the hollow point at that speed combined with entire shape of the projectile is creating some form of aerodynamic effect that is producing this. Or maybe airflow that is hitting resistance just before transonic across its body is stabilizing it even more? Who knows? The only thing I know is that I'm excited to see more!
High powered rifles in competitive shooting use hp rounds bc of this effect. It causes a high pressure air bubble on the tip that goes through the atmosphere more efficiently than a pointed tip does. His data is showing that somewhere above 1000fps is where this effect shines
For those looking to get the .2165's, keep in mind that the performance here is specific to his setup. Each gun has it's own personality so to speak and what works incredibly well in one will not work as well in another. Replacing a worn-out barrel or regulator, etc can and will affect performance with any load. You also need to consider lot number. For example, my M24 clone shot the first lot of Federal SMK BHTP 168 gr at an incredible 1/3 MOA. When I moved to a different lot of the same load the groups opened up to 3/4 MOA. So, definitely consider the load(s) Ted is recommending, but YMMV.
That's what I was gonna say but you condensed it nicely. Wonder if the shockwave forming in front of the slug is displacing some of the air, or letting the slug ride the lower pressure air right behind it. Also the group tightening with the increased speed can be due to barrel harmonics and (or) a reduced follow through time.
First let me say Ted, I love your channel/ posts, Keep it up. Thank you. This is a great example that shows that BC is not a constant as is too often believed. This might be an example of better stability. or I will have to refer to the boys at Sierra bullets. Sorry I cant put it into words but give them a call they will explain this very well, how or why BC IS dependent on Velocity. There are computer simulations that show what the air does around a projectile in flight at differing velocities I just can not find one right now to refer you too. BE
The air bubble on/in the HP is trapped creating a "tip" on the slug. The higher the velocity the more efficient it becomes because the air bubble is under more pressure from the on coming air. This in turn lowers the resistance the actual slug is facing because of the twirling air inside the HP is under more pressure getting push through the atmosphere by the slug. High powered rifles used for competition shooting use hpbt and not pbt rounds for this reason. How fast is to fast before this has diminished returns? I don't know but with pcp's it doesn't matter but clearly you have just proven that this effect starts to really have benefits around 1100fps and not so much below 1000fps.
This is the channel that got me to buy my first large bore air rifle. I wish I could afford a higher quality one because I have a Benjamin and it's not super great or super accurate..
Hi Ted, great to see you back, making a fantastic video and sharing your knowledge/information with us again. I’m shooting Neilson’s (as I’ve found these the most accurate 24.8gr 217’s) out of my M3 700mm superior @ 974f/s. Zeroed at 50m, they are bang on out to 80m then start to go a little sketchy beyond that. Maybe I need to get them going a little faster?
Another great video Ted. I have more experience of centrefire projectiles and its common for the BC to change with velocity so no surprise here. Keep up the good work !!
Great stuff here Ted you will find that the 1:14 twist shoots really well out at farther distances and the faster twist has a lot to do with that BC number you came up with here
Probably the same concept like an arrow flying. You perfectly found the speed needed to stabilize the slug in the air. When a arrow is shot at a slow speed the fletchings need to be larger to get the same bite as the smaller fletchings at a higher speed. Like a fighter jet. They use 100% power as slow speeds because they are falling from the sky. When they actually get to optimum flying speed they stabilize. I'm pretty sure that's what you are witnessing with your slugs.
to a point but if the bow is correctly tuned the arrow will fly straight with no fletchings in other words the only thing on the shaft is a nock and a field point and no fletchings that is the correct way to tune a recurve or longbow it must be in harmony
Amazing Ted! Would be interesting to try another barrel (the same) and see if you get the same results🤔 This would then show you have found your nirvana combination. Also cleaning the barrel to see how that affects your groups. It is amazing how far air rifle technology has come in a few years! Great video!
Rotation of the slug makes the air travel a longer distance along it. This would make the slug virtually longer. With 335m/s the slug should rotate about 20k times per minute.
Great to see you posting again sir! I''m always tickled when I see a Ted notification on my phone...lol. As for what's happening, I've watched your video twice now and am definitely going to give it some thought. Great content as always! Take care my friend!
Ted, I have encountered something similar to this shooting .216 KOs when upping the speed from (normal) 960 fps to over 1020 fps. Had to change the BC from .89 to 1.25 to get Strelok to "match up" predicted vs actual POI. Didn't make sense, so I re-checked all my input data and found that the scope height value was no longer correct(by shooting a target 10 yards away) when shooting at the higher speed. When I input the new scope height and returned to using a BC of .92, all the Strelok click info "trued up" again. You can test if your scope height is correct or not with your new faster setup by shooting at a target that is much closer(10 or 15 yards) than your scope zero(50 yards) where BC doesn't matter that much. See if the Chairgun predicted holdover match actual POI or not.
Here is the response I put up on my group Precision Airgunning So, does anybody want the answer and explanation? Its really quite simple! Ok So, Teds theory of a .22 calibre 30 grain slug with a manufactures published BC of 0.095 having a BC of 0.180 is not only wrong, but absolutely bonkers. So lets start with some basic ballistics. Using a G1 standard BC drag models the BC is not fixed, it is in fact dynamic and changes with velocity and bracketed into velocity bounded segments. BC is normally the first thing an inexperienced user/shooter will manipulate, mainly because its the one thing that they least understand. I mean people find comfort in that they believe their velocity is 100% correct because their chronograph tells them so, we wont go into chronograph read error in this subject but just keep in mind that it does exist! A few other things to keep in mind on this sort of situation is - Range error, velocity error, environmentals, false zero and scope tracking error, to name a few, they all exist. Anyway moving onto the mysterious issue that has got all the top dogs confused! In shot ill just go out ad say it - Scope height, yes it is that simple folks an here is why. If you look firstly at Ted's Rifle set up he has a Saber Tactical back bone rail with inbuilt 20/30 MOA built in, some sort of scope base with built in adjustable elevation,, scope mounts and then the scope, just look at the scope height its crazy high. Then move over onto his Chairgun Pro data where his inputted data states that his scope height is 3.75",crazy high! Essentially what this is causing is excessive or an acute angle with regards to line of sight relevant to bore line. So some more basics, when any projectile leaves the bore regardless of velocity (500 - 4000fps for example) the projectile slows down and and begins to fall away from the line of sight (Gravity) immediately and continues to do so. So how do we hit targets at 100,200,500,1000 yards away, well we add trajectory into the equation via the scope, effectively adding ark into the equation, or lobbing bullets in laymen talk. So in order to order to hit a target at distance the projectile has to leave the barrel and leave the bore line to meet or match the line of sight, (primary (1st) or secondary (2nd) zero) With airguns, because generally they are used at closer ranges when compared to long range centre fire rifles we have to be a little more, lets call it aggressive with the angle created through our scopes in order to match our POA vs POI. This only seems to effect airguns, largely because of what I said above and their close range usage. Im sure some of you guys who shoot either sub 12ftlb air rifles, or a better example is night shooting close range rats at say 20 yards with a perfect 20 yard zero, notice how if you aim directly at a 30 - 40 yard rat you will shoot clearly over the top of it, but then a 50 -60 yard rat you can aim straight at it and hit it, this is the primary (Close) and secondary (far) zeros \I was talking about before. In Ted's situation he has come across the exact same problem but at just a further distance out, this is due to his excessively high rifle scope. To meet his 50 yard zero he will have to have some serious angle dialled to mach his POI vs POI. Once he shoots and hits his zero at 50 yards, the slug, particularly at higher speed will shoot through the line if sight and continue on its upward path above the line of sight to around 70 yards before coming back down through the line of sight back town to his distance of 100 yards. this gives the impression that the projectile is shooting flatter when it is not, its just got a greater arch due to the excessive built in scope height. I hope I have explained it in a way that it can be understood, ill add some Strelok screen shots to demonstrate that just by changing scope height can manipulate the POI down range. Ted simply has just hugely manipulated the BC value of the projectile to the point that it matched his real world DOPE - wrong on every level! I hope this clears this mystery up, just take note that we can simply explain Ted’s findings by simply matching his Correct scope hight and manipulating various scope hight settings to vary results and not BC, if you take one thing from this, make sure you pay attention to scope hight!
You can get the same results by slightly altering far zero. Also when he shot his 50 yard shot after dialing 5moa for 100, his shot at 50 is exactly 5moa high.
I ran a trajectory test on the .177 JSB KnockOuts, with a posted BC of about .047 at 970 FPS. Then I fed the data into Strelok Pro. Of course using the BC provided by JSB didn’t match the real world data I’d collected, so I used the BC truing function and came up with a BC closer to .09. The shot chart in the app was within a click of my data as far out as I had data so far collected. BC is speed dependent. Are manufacturers shooting at slower speeds? Are they using a conservative “at least this good” number? Are they calculating over longer distances which leads them to use a lower average speed in the calculation? Is Wisconsin’s dairy air magically slipperier? Thanks for raising questions Ted!
Chris Turek did some groups at around 1200 fps. He had some pretty good success I thought. There is potential for airguns to operate at supersonic speeds. I get that the whole point of air is to keep it quiet, but I'm absolutely sick of everyone defaulting to "you can't shoot air projectiles over 1000 fps, it won't work". That's a pile of malarkey. I truly believe you can and it's going to become a lot more normal one day.
To be clear I'm not saying you can just launch things out there at 1400 fps. I think you need several things in harmony to still maintain good grouping / accuracy / precision. Most important being twist rate. What's perfect for 100 yards may not be perfect for 40 or 50 though. Everything is a trade off. Either way, keep pushing the envelope Ed. You're work is, and always has been quite important and we appreciate you.
Hey Ted Have you tested your number with Strelok Pro? Double is better than one BC calculator... And it would be interesting to shoot at 300 yards now. if the settings are correct... Greetings Rick
Oh Ted...total geek speak. Now I'll have to watch this again...or more. Hopefully I'll get it better but either this is great. Missed you at Trenier Outdoor shoot. Hope to see you in September.
Hi Ted, i know this is an old (relative post) but hers is my idea, the ballistic coefficient on some shapes of "slug" is NOT LINEAR !! as the slug approaches the speed on sound and we know the destabilisation issues of traversing the speed of sound. Drag is caused by the air stream going past the side of the pellet. The nose of the slug or pellet builds up a pressure cone in front that helps the airflow around the projectile. But it still allows the air to slide down the projectile so your changes in speed are affected by the shape and "balance" of the projectile. ( look at a Sherman tank shell when fired, its not flying straight !!! but pointed up slightly against the ballistic curve !!) but that's not the point, im just saying different projectiles act differently. ( How some pellets FLY by different shapes and C of G positions is another subject) The air stream is working with the projectile shape and affecting its coefficient as a result but in a linear fashion. Up to a point, When you are very close to the speed of sound and you were right on the edge, you are now starting to create a real shock wave and although the airstream is not creating a sharp edge that produces the destabilisation and CRACK sound, it HAS created a deflection in the airstream that has started to leave the side of the pellet.. that's where the shockwave phenomenon starts by the airflow leaving the side of the pellet, and moving forward eventually creating a hard shockwave. This is what changes the coefficient dramatically from the predicted drag figures.. suddenly the drag drops in this small zone when the speed increases. Inversely when the speed drops around this point the drag slope changes and drag increases as the skin effect is re-established. This reverse curve is only there for a very slight variation on speed and is dependant on the profile weight and C of G of the projectile. This is why Chuck Yeager had the reverse control phenomena just as he approached the speed of sound, and had to fly through it by increasing the speed to regain control. Also affected by temperature, humidity and earth rotation etc. it's not a useable zone as the natural drop in speed over a few tens of meters will have left this variable zone.. That's why aircraft don't fly just below the speed of sound in that slightly better efficiency zone because it's so small.. Ive watched all of you videos and loved and learnt from all of them, and ive seen you shoot shell casings at the range just a little too hot where some pellets were flying dead straight and others were getting destabilised as they were affected by traversing the speed of sound. You said then that they were a little hot, and we all know the effect, but the little blip just before this critical speed is affecting the drag coefficient and upsetting your figures...just lower the speed by 10 fps and the curves will be predictable again. That's my theory, I do electronics and there is often a negative reaction in oscillations just before a positive one. colin
Hi Ted. Great video as always. Is it possible that with the change in velocity that your barrel is vibrating differently and the slugs are exiting while your muzzle is pointing higher? Sidenote: You could verify if the BC is actually increasing if you had another chronograph at your target to measure the velocity at 100 yards. Thanks!
The .216 is amazing in my Liberty and my Avenger. The .2165 isn’t to bad either but not as good in a Nova Vista barrel. Really happy around 900-940 with 20.1 grain. That said they my not like another barrel from the same company. Pays to buy variety when testing👍💯. All that aside I believe what your experiencing has to do with twist rate, sectional density, and speed. A slower twist rate and lower velocity will produce more drag if I have my head wrapped around this right. Hopefully you will do a follow up video on this.
Is the faster speed creating a "slip stream" type effect turning the slugs more into a boat tail? Creating a pressure pocket in front, AND in the back?
I don't know what's happening either... but I like it. ;) What it means to me is that shooting slugs 200+ yds without massive hold-over may be possible... and slug BC may be massively underestimated giving us even greater potential accuracy. I'll have to try this with my Airforce Condor. Thanks Ted! :)
Calculate the arc of flight, trajectory. Find the highest point and sight in zero at that distance. If you shoot further adjust up AND the closer you get you will need to adjust up again.
Ted have you measured the barrel rifling to see what depth the engraving is on the soft led slugs? I plan to use javelin 40gr gen 2. Building a custom barrel on my fx m3
Thank you. Yours is the information I trust the most and look forward to each installment. My M3 factory 700mm shoots pellets great but is giving me fits with slugs. Not sure where to start. 22cal.
I only shoot pellets, but I still adjust my BC to get it spot on. And I have yet to find a manufacturer BC that's actually perfect. And the BC I end up with after shooting/testing a pellet is always lower than what they say! The actual BC number is kinda weird to me because just to change the POI an inch at 100 changes the BC number a lot! But I don't really care what the number is, or how my BC compares to the one given by the manufacturer... all I care about is that it's correct for me! Thanks for the video! I always enjoy listening to you & learning! ✌️
Enjoyed the vid, and you did explain it clearly enough for me to follow along. I'm sorry I can't help with the ballistic question, so my best suggestion is to perhaps add some Benny Hill music when high-speed scope-cam Ted heads to the target.
Hi Ted , really great and interesting video, with that BC confirmed at 100 yards and add to the fact that the slugs are shooting 100 plus fps faster than what Nielsens do at say 1000fps I think it would be safe to say that you are flattening out the trajectory or ballistic curve , so then enter your average speed into something like strelok shoot at say 200 yards or even at 250y which ever you feel comfortable with but it has to be quite a bit further than 100 yards and see where strelok tells you to dial for say 200 or as far as you are willing to shoot and see if the ballistics match up , the reason I say this is because if 100 yards is the longest distance you are going to shoot then that’s great but like most of us we all like to test ourselves to hit things further away whether that’s cans of pop golf balls or hunting you will need to see how that BC matches up to your turrets at further distances , sorry if this is a boring long ass comment lol but I would like to hear your thoughts on it , all the best G.
I am seeing exactly the same. FX Maverick 700mm, Superior liner, H&N HP 27gr .218. Claimed factory bc 0.95. @920fps I see bc of .097, when I crank them up to 1000fps bc leaps to 0.131. Used same method to verify as you did, also did verification at every 10m from 40m zero all way to 100m. Not complaining, but shocked me. Just managed to get first supply of H&N HPII 27gr Slugs, so will need to try with them???
Since the sectional density is related to the ballistic coefficient by the form factor, could it be that the determination of the form factor is the issue? I mean is there a standard form factor that we can apply to a pellet or a slug? Also, are using a G1 or a G7 calculation for the ballistic coefficient? You may have said it on the video and I just missed it. And I definitely agree that you should put a chronograph downrange. I think it would be important to understand what the integral would look like for the change in velocity over time and distance. It's possible that the slug coming out at 900 ft per second has close to the same velocity and 100 yd is the slug coming out at 1100 ft per second.
I notice in your BC calculation, you have the temperature as 0 degrees Fahrenheit. Was this correct, as it will make a difference to the calculated air density and the Mach number for the reference drag law which in turn could have a big effect on the calculated BC (it will be much larger than it should be).
Hi Ted, First off I'm no mathematician but you might be forgetting about the angle change when zeroing, At the lower velocity you tilt the barrel higher to compensate for the distance to zero (50yds) if the velocity increases that angle changes to hit the 50 yds zero. I put your data into the Hornady calculator, here's what it says.
1000fps, BC 0.09, 26gn projectile, scope 3.75" above the bore, 0yds= -3.8", 25yds = -0.6", 50yds = 0", 75yds =-2" 100yds =-6.9".
1100fps, BC 0.18, 26gn projectile, scope 3.75" above the bore, 0yds= -3.8", 25yds = -0.9", 50yds = 0", 75yds = -1.2" 100yds = -4.5".
1100fps, BC 0.09, 26gn projectile, scope 3.75" above the bore, 0yds= -3.8", 25yds = -0.8", 50yds = 0" , 75yds = -1.5", 100yds = -5.5.
I read somewhere that the location of the scopes reticle adjustment relative to the triangle created by the barrel and scope axis relative to the projectile start point will make a difference in the amount of clicks needed to reach zero (ATN web site I think), your rifle has the projectile a long way behind the scope reticle adjustments, in other words your adjustments are having a greater effect than if the projectile was below them
First of all, I want to say I am so happy to see new content on this channel. Ted is a top-notch marksman and I have enjoyed these videos for years. Regarding the BC - why not put another chronograph at 100 yards and measure that velocity compared to muzzle velocity and calculate BC that way.
Yep. Time to bite the bullet and buy a damn LabRadar.
@@TedsHoldOver teddy you have done so much for us you have a patron or donation area? Shit I’d buy your only fans if you do weekly Airguns hunts on it😂
Yes! Verry interesting to know what speed the pellet/slug has on impact, at 50 and 100m.
@@TedsHoldOver You spent over $1000 on slugs... lol
@@mikecollins8241 not just slugs, all the slugs 😂. Thats what happens when you find “The One”
Thank you for the vid; it is quite stimulating --- which makes you the elite provocateur of thoughts, avvocato del diavolo, and rouser of enquiry into the logical/illogical world of Ballistics. This video shows that despite efforts to make sense of logistics with the behaviour of missiles, all pre-conception seems futile. You, sir, have dared to be the Sherlock Holmes of your vocation. "The only thing that remains constant is change," attributed to the Greek philosopher Heraclitus, seems to ring true in your efforts. To reiterate Mr. Holmes, "When one eliminates the impossible, whatever remains, however impossible, must be the truth". Thank you again your efforts. Stay well.
I believe you found the perfect speed and twist rate for that specific lenght and weight over that specific distance. In other words, the slug flies true through the trajectory curve for perfect aerodynamic angle of attack. No nose up or down during the flight through the trajectory curve. Just perfect. The choke of the barrel will also play a big role here on how it releases that slug (angle of attack). It's like finding a needle in a haystack, possible but very rare. Good football quarterbacks have the ability to throw, release and spin the football just right to achieve perfect angle of attack, speed and twist for optimal flight in order to achieve maximum distance with the least effort. Everyone who has thrown a football enough has at some point found that "feeling" of a perfect release. This is very difficult to achieve with a barrel in a gun. I believe you have found your unicorn.
who better to explain than a slug designer.
@@XM913CG lol… great theory, but he’s incorrect
@@Oregon-airguns agree, what Rolfe is saying is kind of right but does not explain Ted results. That’s simply down to incorrect data and operator error!
The inability to find the perfect ammo for YOUR gun is what makes these air guns nothing but cash cows for the manufacturers. You are all chasing the wind! Ted got lucky....after admittingly spending OVER 1K on ammo. REDICULOUS.
The day I found my “perfect release” I started preparing a nursery.
As an old high power rifle competitor, 200 to 600yds and 1000 yards. I am enjoying seeing you go thru the exact same testing to achieve the best accuracy you can from your equipment in an air rifle. Your finding that a pellet dia. in ten thousands of an inch can make such a huge difference in performance. My shooting was 50 years ago, and I heard of some top shooters that would go to the sierra factory and mic bullets coming out of the bullet making machine until the die wore down enough to get the dia they wanted and then take the next ten or twenty thousand bullets for reloading because that dia is what their barrel liked.
Outstanding shipmate. Press on. USS Kitty Hawk CV-63. Jan 1980 to July 1983. Air gunner for life.
After years on UA-cam, this is still my favorite channel. I will by an FX next year because of this guy.
It’s been 1 year. Well darn close! But you should have got your tax return by now. Soooo, how are you liking your new FX???
@@Oregon-airguns lol, I'm working on it. Finally got my air setup ready to go. Bit by bit.
@@tadracket448 let me give you some advise. Steeer clear of fx… take a look at the Vulcan 3. It’s a straight killer right out of the box. Shooting avs slugs. M channels not nearly good as teds. But I’ve been down the fx road and it was a total nightmare.
Hi Ted. I just tested this with my LabRadar. I used the same barrel, 800mm 1:14 twist and same slugs, NSA 31.2gr .2165 . I shot a 15 shot string at 100yd. Average muzzle velocity was 1,087 and average velocity at 100yds was 941. Taking air temperature, station pressure, and humidity into account I got a G1 BC of .132. RA4 BC was .104.
Absolutely spot on Tyler like we have previously discussed. Absolutely no way a projectile can double its BC, it is impossible. Period!
I looked on FX's website and they don't offer an 800mm barrel in 22 cal. Who do i contact to purchase the same set up Ted has?
Ted for me this has just blown my mind your dedication to education of the masses is incredible, thank you . Keep doing all that you do especially nailing the pigeons.
Hope you're doing well Ted, it always makes my day when you upload new content!
I've also ran into many ballistic "mysteries" but in the end they were simply not taking into account of atmosphere conditions or user error. Temperature and altitude density have HUGE affect on BC/trajectory. Zero one day and not readjust to new weather condition into the ballistic calculation will through you off big time. I've learned the hard way and always validate zero and reset atmosphere conditions in ballistic solver with minimum local weather station information, I try use a weather meter for my ballistic solver and make a point to update the information EVERY HOUR!
Ted: Love your show and learned a ton from you especially on tuning the gun. Keep up the great work!
More Spin, Less Drag
In this article, we look at how twist rate and stability affect the Ballistic Coefficient (BC) of a bullet. Again, this topic is covered in detail in the Modern Advancements book. Through our testing, we’ve learned that adequate spin-stabilization is important to achieving the best BC (and lowest drag). In other words, if you don’t spin your bullets fast enough (with sufficient twist rate), the BC of your bullets may be less than optimal. That means, in practical terms, that your bullets drop more quickly and deflect more in the wind (other factors being equal). Spin your bullets faster, and you can optimize your BC for best performance.
I think what you're seeing is your finding the sweet spot of the spin rate, ,this increased the BC which effectively increased the accuracy for longer ranges. I would almost guess the bullet as two sweet spots one low at the smaller BC and the one you have found...
I agree: it would make sense that a higher initial velocity, and greater rate of spin, would ccause more "lift" from spin "traction" as the bullet bites it's way thru the air. I love this stuff, as I've been an avid handloader for years, and the mysteries keep coming! "What we THINK we know, vs What we find in testing"
You right, if you rise your bullet speed you change its gyroscopic stabilizations. You can calculate one and check if its the main factor here
@@mikecollins8241 You, sir, are a THINKING man in the best sense. I have echoed your statements for the many years of searching for truth in all things in this world. Thank you for your maxim. Stay well.
The inability to find the perfect ammo for YOUR gun is what makes these air guns nothing but cash cows for the manufacturers. You are all chasing the wind! Ted got lucky....after admittingly spending OVER 1K on ammo. REDICULOUS.
So what about the drag increase in transonic region? At 1100 fps(about mach 0.97 drag on projectile at the muzzle is so much higher than subsonic speeds and its nothing to with spin rate or even type of the projectile (bullet,slug, airplane!....)what you saying could be true in supersonic projectiles like canterfire rifle bullets,but here we are dealing with subsonic airgun projectiles, clearly something is going on in this case,but as ted says, it must be impossible!!
Wonderful video, I've been playing with the neilsen slugs in 21 and 23 grain in my Avenger, I upped my reg pressure about 150 psi to 2250, and I noticed a drastic difference in the amount of drop beyond 75 yards..much more so than I'd expected. Now I'm enjoying some flatter shooting, but I've yet to push them across the chrony..that's the next step 😏 thanks for another great video, appreciate your dedication to the airgun community and sharing what you learn.
Ted's videos are quality over quantity and once again, we appreciate it. Well worth the wait. Another GREAT video Ted!
I really enjoy listening to ballistics nerds (like you and Matt) heading into the weeds of researching and explaining what's going on with slugs & pellets in flight. I'm not sure what percentage I'm missing, but it's fascinating watching you work on it.
Received my first fx wildcat today, you posting is still the best thing thing that has happened today, Ty Ted!!
You're going to LOVE that wildcat. I grab my WC a lot more than my impact or any other rifle. It's just the perfect balance of comfort/accuracy/power. If someone were to ask what their first FX should be, I would recommend the Wildcat BT, hands down.
I'd be very happy i could get a half-inch group at 50y, never seen such a group at 100 yards, Amazing!!!
Internal ballistics are a funny thing. Barrel whip can throw the same bullet to two sweet spots at different velocities. The first (lower velocity) shot may be whipping the muzzle down slightly and giving you a stable muzzle exit at with the muzzle low. The higher velocity may be throwing your groups higher. This gives you a different number to calculate BC than the 'accurate' number. You'd have to check velocity at multiple points on the trajectory and see if the velocity is dropping with the BC.
The other alternative is that the BC is changing due to transonic interactions with your bullet profile. Bullets do weird things whey they try to push air around them at supersonic speeds, even though the bullet itself isn't supersonic. You could be getting a better BC because of the supersonic flow characteristics of this particular profile. Me, I avoid transonic as much as I can. With my .44 Magnum rifle loads, I stay at about 1,050 FPS. Bullets that fly much faster risk running into weird stuff, as you may have experienced. Only strike against this theory with your bullets is that they slow down REALLY quick to full subsonic flow.
Brilliant comment: Measure velocity drop; not POI shift.
yeah, you missed the point - he measured the difference with the same velocity 1100 at 100 and 50 and compared the difference. Pay attention, focus and don't speculate
Great video Ted ! I’ve watched you from the start , and you got me with you never ending quest for top performance. With the right equipment, and understanding the science the hours you spend on target make it all come together .thanks for sharing your system and how it works ! I’m still amazed at shooting nickels at that distance………with air…….. !
Good god! Your still the goat! I was like 👍 2k btw. I’ve noticed the same thing with different lots of 22lr some lots come out to .170 bc and others .123 same exact bullet, even weighed them. Billets we’re Norma Tac they vary in velocity a lot from lot to lot. Some lots 950 others 1100. Thx again Ted!
I'm a little discombobulated in this one, but somewhere in the rambling there IS a point. ;)
I remember when I was a kid, my grandpa would talk to me about a “magic velocity” for his .22 cal while I sucked feverishly on a werthers original. He was a professor in physics and told me some jibberish about how at a certain velocity and twist rate, outward forces such as the effect of wind and even RAIN would have little to no effect. Those numbers I suppose, would apply to slugs from an air gun as well. Matter of fact, I know they do “;) Dam, those Werther originals are good…
@@2cthetruth this is why I come to the comments. Never would've thought of this. I need to get some werthers.
@@2cthetruth I get the 34 ounce bags from Walmart for best price per lozenge economy. 🍬
They make chewy ones now too! Just found them a couple days ago. They're very, very good.
Hi Ted, What you are observing is the effect the speed and hollow point has on the BC. Higher the velocity of the projectile = higher BC and the hollow point traps air (bubble) and the higher the pressure the harder the bubble is and the more it's aerodynamically shaped which results in reduced drag and higher BC.
Mythbusters "golfball effect" and "tailgate" has very nice visualization of the phenomena.
Great to see you back Ted!
Hi Ted, great info on the airgun and new slugs. That is pretty cool what you are getting with these slugs! I had one thought which is - why introduce the scope change into your calculation? Simply shoot at 50 yards and it impacts the target, you can make it near zero but quite honestly it does not destroy the point of aim if it hits a few inches low. Then simply back the target up, continue to shoot at the same aiming point. Measure the difference between the two groups and you have the drop at 100 yards. The aiming point is quite irrelevant so long as the aiming point is the same each distance, I actually prefer to make a cross with a heavy marker or even tape depending on what I am doing. That way no scope calibration issues are introduced, etc. The drop is what the drop is. Just have to shoot at the same point, leave the scope alone. Keep on killing those starlings!
Hi Ted. You're the man broseph. Come on out to new Hampshire and we'll rip up some grey squirrels. I love all your videos I love how you get in depth and explain all the math in a way that's made simple. Keep up all your good work and keep up all the videos Ted. You are the balls and I always look forward to your next video. Let me know if you are ever in New England we can tear it up
Always a pleasant surprise when you post a new one. Good stuff.
Good to see you back Ted!! On the BC is it possible that the hollow point is creating a slip stream affect like a pickup truck box does with the tailgate closed air moves freely over the truck. With the slug the cup fills with air that is compressed whether going fast or slow causing the slug to stabilize.
BC is defined by change in velocity between 50 and 100 yards. Delta in POI could be deceptive because it includes the effect of barrel harmonics.
Summary of insightful statement by RyeOnHam
nope, what he wrote was dumb because he doesn't pay attention and makes up crap that sounds smart to other people that don't understand basic math and don't pay attention. Barrel whip is not a variable because he was shooting at the same speed at 100 and 50 yards. The barrel harmonics doesn't change because of the distance you shoot or because you aim at different thing....
Ive watched you since the edgun matador days. The 130 yard pigeon shot got me into the air world. Ive got an impact m3 .30 cal shooting knockouts 900-905 sub moa out to 150. Jsb pellets 50.15 gr also mostly moa to 150 with some flyer. Stx standard barrel @910-915. Wish I could post pics here. Great to see the content again
What reg pressure and valve settings? Just curious, I have also found 50.15 knockout slugs to prefer 900-911 fps and 50.15 jsb pellets around 870-875.
@@nobs2767 1:165, 2:127 4+ a few click on tuner 12 on the wheel and 4 lines on the valve
I love the Nielsen slugs in my 177cal. They work so well that I haven't tried anything else.
I wonder if the air hitting the hollow point at that speed combined with entire shape of the projectile is creating some form of aerodynamic effect that is producing this.
Or maybe airflow that is hitting resistance just before transonic across its body is stabilizing it even more?
Who knows? The only thing I know is that I'm excited to see more!
High powered rifles in competitive shooting use hp rounds bc of this effect. It causes a high pressure air bubble on the tip that goes through the atmosphere more efficiently than a pointed tip does. His data is showing that somewhere above 1000fps is where this effect shines
@@adamdearien5975 that is my theory as well, I can imagine he would see decreased BC if the slug was not HP.
For those looking to get the .2165's, keep in mind that the performance here is specific to his setup. Each gun has it's own personality so to speak and what works incredibly well in one will not work as well in another. Replacing a worn-out barrel or regulator, etc can and will affect performance with any load.
You also need to consider lot number. For example, my M24 clone shot the first lot of Federal SMK BHTP 168 gr at an incredible 1/3 MOA. When I moved to a different lot of the same load the groups opened up to 3/4 MOA.
So, definitely consider the load(s) Ted is recommending, but YMMV.
As you get closer to the speed of sound, shock wave is formed. The slug may be drafting in the shock wave.
That's what I was gonna say but you condensed it nicely.
Wonder if the shockwave forming in front of the slug is displacing some of the air, or letting the slug ride the lower pressure air right behind it.
Also the group tightening with the increased speed can be due to barrel harmonics and (or) a reduced follow through time.
I was thinking that too, Ted hasn't responded yet though, Thanks for the content Ted, keep it up dear boy!
^^^Looks like the scammers are on the prowl.^^^
Thank you for your videos! You have taught me so much. I loved hearing you teach the scouts, I love learning from you too
nice to see you again after years
I cant believe how accurate your gun is, its great
First let me say Ted, I love your channel/ posts, Keep it up. Thank you.
This is a great example that shows that BC is not a constant as is too often believed. This might be an example of better stability. or I will have to refer to the boys at Sierra bullets. Sorry I cant put it into words but give them a call they will explain this very well, how or why BC IS dependent on Velocity. There are computer simulations that show what the air does around a projectile in flight at differing velocities I just can not find one right now to refer you too.
BE
Great job Ted, love what you do here.
The air bubble on/in the HP is trapped creating a "tip" on the slug. The higher the velocity the more efficient it becomes because the air bubble is under more pressure from the on coming air. This in turn lowers the resistance the actual slug is facing because of the twirling air inside the HP is under more pressure getting push through the atmosphere by the slug.
High powered rifles used for competition shooting use hpbt and not pbt rounds for this reason.
How fast is to fast before this has diminished returns? I don't know but with pcp's it doesn't matter but clearly you have just proven that this effect starts to really have benefits around 1100fps and not so much below 1000fps.
we hope to see the white glasses back 😎😎🔥🔥 I'm happy to see the legend back
That was awesome, hope you continue to teach us a thing or two thanks for all your hard work.
Awesome ted!! so appreciate your contributions
This is the channel that got me to buy my first large bore air rifle. I wish I could afford a higher quality one because I have a Benjamin and it's not super great or super accurate..
Nearly anyone can afford and Avenger. Get one.
What Benjamin do you have? Try Airgunnationforum as good deals are there all the time for air rifles and PCPs.
Hi Ted, great to see you back, making a fantastic video and sharing your knowledge/information with us again.
I’m shooting Neilson’s (as I’ve found these the most accurate 24.8gr 217’s) out of my M3 700mm superior @ 974f/s. Zeroed at 50m, they are bang on out to 80m then start to go a little sketchy beyond that. Maybe I need to get them going a little faster?
love watching you ted thank you so much for all that you do for us.
so excited everytime i see a new video of yours!
Great info. Will definitely be trying. Thanks for sharing.
Transonic airflow does strange things. You have found one of those things.
Another great video Ted. I have more experience of centrefire projectiles and its common for the BC to change with velocity so no surprise here. Keep up the good work !!
always a good day when we get a new Ted video
Great video Ted, thank youvery much for all the useful info, and data
Great stuff here Ted you will find that the 1:14 twist shoots really well out at farther distances and the faster twist has a lot to do with that BC number you came up with here
Wrong!
Good lord is right.. That disappearing head trick was amazing 👏
Probably the same concept like an arrow flying. You perfectly found the speed needed to stabilize the slug in the air. When a arrow is shot at a slow speed the fletchings need to be larger to get the same bite as the smaller fletchings at a higher speed. Like a fighter jet. They use 100% power as slow speeds because they are falling from the sky. When they actually get to optimum flying speed they stabilize. I'm pretty sure that's what you are witnessing with your slugs.
That is a great concept.
to a point but if the bow is correctly tuned the arrow will fly straight with no fletchings in other words the only thing on the shaft is a nock and a field point and no fletchings that is the correct way to tune a recurve or longbow it must be in harmony
It would be interesting to try a LabRadar chrono and see what it says about the BC.
Yep. Just ordered one. OUCH at the price! :)
Set up an address on Pattoron and I’ll send you a donation
KEEP UP THE GOOD WORK
TOM
Mystery for sure, but your bumble BC math looks right. Love it. Thanks. Jess
Amazing Ted! Would be interesting to try another barrel (the same) and see if you get the same results🤔 This would then show you have found your nirvana combination. Also cleaning the barrel to see how that affects your groups. It is amazing how far air rifle technology has come in a few years! Great video!
You are a mad scientist. Follow the MOA
Rotation of the slug makes the air travel a longer distance along it. This would make the slug virtually longer. With 335m/s the slug should rotate about 20k times per minute.
I will up my speed and try to replicate what you have done here. Great video!
This the guy who got me into air guns
Great to see you posting again sir! I''m always tickled when I see a Ted notification on my phone...lol. As for what's happening, I've watched your video twice now and am definitely going to give it some thought. Great content as always! Take care my friend!
Ted said 1:14. Were you typing instead of listening?
@@rickoshea8138 ah, must have missed it when my daughter came down asking questions. Thanks. 👍
Ted,
I have encountered something similar to this shooting .216 KOs when upping the speed from (normal) 960 fps to over 1020 fps. Had to change the BC from .89 to 1.25 to get Strelok to "match up" predicted vs actual POI. Didn't make sense, so I re-checked all my input data and found that the scope height value was no longer correct(by shooting a target 10 yards away) when shooting at the higher speed. When I input the new scope height and returned to using a BC of .92, all the Strelok click info "trued up" again.
You can test if your scope height is correct or not with your new faster setup by shooting at a target that is much closer(10 or 15 yards) than your scope zero(50 yards) where BC doesn't matter that much. See if the Chairgun predicted holdover match actual POI or not.
Ted's got the same problem as me, haul ass to the target and then be out of breath when I get back to the gun.
I am bumblebeezed by this video
Here is the response I put up on my group Precision Airgunning
So, does anybody want the answer and explanation? Its really quite simple!
Ok So, Teds theory of a .22 calibre 30 grain slug with a manufactures published BC of 0.095 having a BC of 0.180 is not only wrong, but absolutely bonkers. So lets start with some basic ballistics. Using a G1 standard BC drag models the BC is not fixed, it is in fact dynamic and changes with velocity and bracketed into velocity bounded segments. BC is normally the first thing an inexperienced user/shooter will manipulate, mainly because its the one thing that they least understand. I mean people find comfort in that they believe their velocity is 100% correct because their chronograph tells them so, we wont go into chronograph read error in this subject but just keep in mind that it does exist! A few other things to keep in mind on this sort of situation is - Range error, velocity error, environmentals, false zero and scope tracking error, to name a few, they all exist. Anyway moving onto the mysterious issue that has got all the top dogs confused! In shot ill just go out ad say it - Scope height, yes it is that simple folks an here is why. If you look firstly at Ted's Rifle set up he has a Saber Tactical back bone rail with inbuilt 20/30 MOA built in, some sort of scope base with built in adjustable elevation,, scope mounts and then the scope, just look at the scope height its crazy high. Then move over onto his Chairgun Pro data where his inputted data states that his scope height is 3.75",crazy high! Essentially what this is causing is excessive or an acute angle with regards to line of sight relevant to bore line. So some more basics, when any projectile leaves the bore regardless of velocity (500 - 4000fps for example) the projectile slows down and and begins to fall away from the line of sight (Gravity) immediately and continues to do so. So how do we hit targets at 100,200,500,1000 yards away, well we add trajectory into the equation via the scope, effectively adding ark into the equation, or lobbing bullets in laymen talk. So in order to order to hit a target at distance the projectile has to leave the barrel and leave the bore line to meet or match the line of sight, (primary (1st) or secondary (2nd) zero) With airguns, because generally they are used at closer ranges when compared to long range centre fire rifles we have to be a little more, lets call it aggressive with the angle created through our scopes in order to match our POA vs POI. This only seems to effect airguns, largely because of what I said above and their close range usage. Im sure some of you guys who shoot either sub 12ftlb air rifles, or a better example is night shooting close range rats at say 20 yards with a perfect 20 yard zero, notice how if you aim directly at a 30 - 40 yard rat you will shoot clearly over the top of it, but then a 50 -60 yard rat you can aim straight at it and hit it, this is the primary (Close) and secondary (far) zeros \I was talking about before. In Ted's situation he has come across the exact same problem but at just a further distance out, this is due to his excessively high rifle scope. To meet his 50 yard zero he will have to have some serious angle dialled to mach his POI vs POI. Once he shoots and hits his zero at 50 yards, the slug, particularly at higher speed will shoot through the line if sight and continue on its upward path above the line of sight to around 70 yards before coming back down through the line of sight back town to his distance of 100 yards. this gives the impression that the projectile is shooting flatter when it is not, its just got a greater arch due to the excessive built in scope height. I hope I have explained it in a way that it can be understood, ill add some Strelok screen shots to demonstrate that just by changing scope height can manipulate the POI down range. Ted simply has just hugely manipulated the BC value of the projectile to the point that it matched his real world DOPE - wrong on every level! I hope this clears this mystery up, just take note that we can simply explain Ted’s findings by simply matching his Correct scope hight and manipulating various scope hight settings to vary results and not BC, if you take one thing from this, make sure you pay attention to scope hight!
You can get the same results by slightly altering far zero. Also when he shot his 50 yard shot after dialing 5moa for 100, his shot at 50 is exactly 5moa high.
This was a really good video. Keep these up!
I ran a trajectory test on the .177 JSB KnockOuts, with a posted BC of about .047 at 970 FPS. Then I fed the data into Strelok Pro. Of course using the BC provided by JSB didn’t match the real world data I’d collected, so I used the BC truing function and came up with a BC closer to .09. The shot chart in the app was within a click of my data as far out as I had data so far collected.
BC is speed dependent. Are manufacturers shooting at slower speeds? Are they using a conservative “at least this good” number? Are they calculating over longer distances which leads them to use a lower average speed in the calculation? Is Wisconsin’s dairy air magically slipperier?
Thanks for raising questions Ted!
Great video Thanks for all the hard work, you making me want to purchase the FX and putting away my Hatsun Gladius. 25
Did you account for the scope height in your calculations?
Oh yes. Measured with calipers to the mm. 👍
look we all won f...king scammers
Chris Turek did some groups at around 1200 fps. He had some pretty good success I thought. There is potential for airguns to operate at supersonic speeds. I get that the whole point of air is to keep it quiet, but I'm absolutely sick of everyone defaulting to "you can't shoot air projectiles over 1000 fps, it won't work". That's a pile of malarkey. I truly believe you can and it's going to become a lot more normal one day.
To be clear I'm not saying you can just launch things out there at 1400 fps. I think you need several things in harmony to still maintain good grouping / accuracy / precision. Most important being twist rate.
What's perfect for 100 yards may not be perfect for 40 or 50 though. Everything is a trade off.
Either way, keep pushing the envelope Ed. You're work is, and always has been quite important and we appreciate you.
Hey Ted
Have you tested your number with Strelok Pro?
Double is better than one BC calculator...
And it would be interesting to shoot at 300 yards now. if the settings are correct...
Greetings Rick
Oh Ted...total geek speak. Now I'll have to watch this again...or more. Hopefully I'll get it better but either this is great. Missed you at Trenier Outdoor shoot. Hope to see you in September.
Hi Ted, i know this is an old (relative post) but hers is my idea, the ballistic coefficient on some shapes of "slug" is NOT LINEAR !! as the slug approaches the speed on sound and we know the destabilisation issues of traversing the speed of sound. Drag is caused by the air stream going past the side of the pellet. The nose of the slug or pellet builds up a pressure cone in front that helps the airflow around the projectile. But it still allows the air to slide down the projectile so your changes in speed are affected by the shape and "balance" of the projectile. ( look at a Sherman tank shell when fired, its not flying straight !!! but pointed up slightly against the ballistic curve !!) but that's not the point, im just saying different projectiles act differently. ( How some pellets FLY by different shapes and C of G positions is another subject) The air stream is working with the projectile shape and affecting its coefficient as a result but in a linear fashion. Up to a point, When you are very close to the speed of sound and you were right on the edge, you are now starting to create a real shock wave and although the airstream is not creating a sharp edge that produces the destabilisation and CRACK sound, it HAS created a deflection in the airstream that has started to leave the side of the pellet.. that's where the shockwave phenomenon starts by the airflow leaving the side of the pellet, and moving forward eventually creating a hard shockwave.
This is what changes the coefficient dramatically from the predicted drag figures.. suddenly the drag drops in this small zone when the speed increases. Inversely when the speed drops around this point the drag slope changes and drag increases as the skin effect is re-established. This reverse curve is only there for a very slight variation on speed and is dependant on the profile weight and C of G of the projectile. This is why Chuck Yeager had the reverse control phenomena just as he approached the speed of sound, and had to fly through it by increasing the speed to regain control. Also affected by temperature, humidity and earth rotation etc. it's not a useable zone as the natural drop in speed over a few tens of meters will have left this variable zone.. That's why aircraft don't fly just below the speed of sound in that slightly better efficiency zone because it's so small..
Ive watched all of you videos and loved and learnt from all of them, and ive seen you shoot shell casings at the range just a little too hot where some pellets were flying dead straight and others were getting destabilised as they were affected by traversing the speed of sound. You said then that they were a little hot, and we all know the effect, but the little blip just before this critical speed is affecting the drag coefficient and upsetting your figures...just lower the speed by 10 fps and the curves will be predictable again. That's my theory, I do electronics and there is often a negative reaction in oscillations just before a positive one.
colin
Hi Ted. Great video as always.
Is it possible that with the change in velocity that your barrel is vibrating differently and the slugs are exiting while your muzzle is pointing higher?
Sidenote: You could verify if the BC is actually increasing if you had another chronograph at your target to measure the velocity at 100 yards.
Thanks!
The .216 is amazing in my Liberty and my Avenger. The .2165 isn’t to bad either but not as good in a Nova Vista barrel. Really happy around 900-940 with 20.1 grain. That said they my not like another barrel from the same company. Pays to buy variety when testing👍💯. All that aside I believe what your experiencing has to do with twist rate, sectional density, and speed. A slower twist rate and lower velocity will produce more drag if I have my head wrapped around this right. Hopefully you will do a follow up video on this.
Is the faster speed creating a "slip stream" type effect turning the slugs more into a boat tail? Creating a pressure pocket in front, AND in the back?
I don't know what's happening either... but I like it. ;) What it means to me is that shooting slugs 200+ yds without massive hold-over may be possible... and slug BC may be massively underestimated giving us even greater potential accuracy. I'll have to try this with my Airforce Condor. Thanks Ted! :)
for the BC, it could be the point of impact change because the harmonic change in different spring settings.
Calculate the arc of flight, trajectory. Find the highest point and sight in zero at that distance. If you shoot further adjust up AND the closer you get you will need to adjust up again.
Ted have you measured the barrel rifling to see what depth the engraving is on the soft led slugs? I plan to use javelin 40gr gen 2. Building a custom barrel on my fx m3
HELL YEAH! Needed a dose of Ted!
Thank you. Yours is the information I trust the most and look forward to each installment. My M3 factory 700mm shoots pellets great but is giving me fits with slugs. Not sure where to start. 22cal.
Twist rate is to slow with factory liner for slugs.
I only shoot pellets, but I still adjust my BC to get it spot on. And I have yet to find a manufacturer BC that's actually perfect. And the BC I end up with after shooting/testing a pellet is always lower than what they say!
The actual BC number is kinda weird to me because just to change the POI an inch at 100 changes the BC number a lot! But I don't really care what the number is, or how my BC compares to the one given by the manufacturer... all I care about is that it's correct for me!
Thanks for the video! I always enjoy listening to you & learning! ✌️
What is that calculator at the 14:45 mark??
Ted is that a regular shroud over your barrel or do you have tension carbon fiber then a shroud plz let me know ty 😊
Awesome explanation 🤯
Ted are you using and barrel tension kit under that shroud????
Enjoyed the vid, and you did explain it clearly enough for me to follow along. I'm sorry I can't help with the ballistic question, so my best suggestion is to perhaps add some Benny Hill music when high-speed scope-cam Ted heads to the target.
Holy crap I'm getting old... Ted's hair is going grey.
I've been listening to this dude for 12 years.
Hi Ted , really great and interesting video, with that BC confirmed at 100 yards and add to the fact that the slugs are shooting 100 plus fps faster than what Nielsens do at say 1000fps I think it would be safe to say that you are flattening out the trajectory or ballistic curve , so then enter your average speed into something like strelok shoot at say 200 yards or even at 250y which ever you feel comfortable with but it has to be quite a bit further than 100 yards and see where strelok tells you to dial for say 200 or as far as you are willing to shoot and see if the ballistics match up , the reason I say this is because if 100 yards is the longest distance you are going to shoot then that’s great but like most of us we all like to test ourselves to hit things further away whether that’s cans of pop golf balls or hunting you will need to see how that BC matches up to your turrets at further distances , sorry if this is a boring long ass comment lol but I would like to hear your thoughts on it , all the best G.
Can I lend you a period? Here’s a few……
Ted, I'd love to know the your tune. I'm getting same slugs and same barrel.
Welcome back!
I am seeing exactly the same. FX Maverick 700mm, Superior liner, H&N HP 27gr .218. Claimed factory bc 0.95. @920fps I see bc of .097, when I crank them up to 1000fps bc leaps to 0.131. Used same method to verify as you did, also did verification at every 10m from 40m zero all way to 100m. Not complaining, but shocked me. Just managed to get first supply of
H&N HPII 27gr Slugs, so will need to try with them???
Yay! Harry potter of death is back!
Love your vids. They got me into PCP's.
What I took away from moving near the speed of sound when I was in school was throw all your normal assumptions out the window.
Since the sectional density is related to the ballistic coefficient by the form factor, could it be that the determination of the form factor is the issue? I mean is there a standard form factor that we can apply to a pellet or a slug? Also, are using a G1 or a G7 calculation for the ballistic coefficient? You may have said it on the video and I just missed it. And I definitely agree that you should put a chronograph downrange. I think it would be important to understand what the integral would look like for the change in velocity over time and distance. It's possible that the slug coming out at 900 ft per second has close to the same velocity and 100 yd is the slug coming out at 1100 ft per second.
Very interesting and informative video thanks ted 👍🏻
I’m digging the specs! Good vid!
What's both reg settings @ 1100fps ??
I notice in your BC calculation, you have the temperature as 0 degrees Fahrenheit. Was this correct, as it will make a difference to the calculated air density and the Mach number for the reference drag law which in turn could have a big effect on the calculated BC (it will be much larger than it should be).
Nice of you to give everyone a gun, Ted. 😉😂