How to Choose the Best Bullet Weight ~ Sectional Density!
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- Опубліковано 29 сер 2024
- Bullet sectional density has always been the first and reliable guide to proper bullet weight selection, but because ammo manufacturers don't describe it on their boxes, it remains a secret to most shooters. Learn how understanding this very old and simple number, known by experienced shooters for decades, can unlock the mystery for you!
I watch many youtube videos but I learn more about firearms from yours than any other. Thanks for that.
👍🏽quality content. You can’t find this on TV
Love the fact that GunBlue 490 has no commercial interest in firearms so his information is non biased and comes from a lifetime of passion for the sport.He is a very honourable man with a placid nature who states exactly what hes found works over the years. A true asset for anyone into firearms particularly hunting
Cheers.
Thank you for the solid advice. No hype just facts, rare these days.
Another great video. A very good friend who was a retired Border Patrolman and shot on the BP pistol team, explained SD and its application to me about 25 years ago. His explanation mirrored yours and I have loaded rifles using his guidance. A 180 grain bullet for my 300 WM for use on bull elk, a 160 grain bullet in a 7MM Rem Mag for use on game ranging from deer to bull elk. A 140 grain bullet in a 280 for use on game ranging from antelope to deer. He once told me that accuracy and the correct application of SD were very important and velocity was truly secondary. I am sure you would have enjoyed conversing with him. It’s too bad he passed ten years ago. Thank you for continuing your information packed videos.
Dear GunBlue490. Another winner. Nice
Dear Sir,
You added sectional density to my vocabably at the very beginning of my Gunblue education in All Things Firearms.
Thank you for furthering my knowledge of the subject.
May you, your family, and your beloved Benny have a Merry Christmas.
I am looking forward to your Christmas based video and the celebration of the birth of Jesus.
God bless,
Warmest regards,
Rick Mansberger and family
GunBlue is hinting at something I've recommended to hunters for awhile: the idea of "sectional momentum." It's just sectional density times speed. Bullets of identical sectional density and construction at identical speeds will have nearly identical penetration and performance on game. The magic .240 SD he advocates here assumes similar speeds as the classic cartridges with which those bullets were mostly used and also assumes the classic cup and core soft point construction. If you are using a particularly fast or slower cartridge, the ideal SD can change. For example, a faster cartridge should use a slightly higher SD because it will flatten more on impact. (ironically, yes, but often higher speeds mean LESS penetration). Conversely, a slower cartridge can get away with a lower SD because the bullet will deform much less on impact and as it traverses the animal.
A bullet of very high SD at moderate speeds can have pretty extreme penetration-- think of the classic 160gr load in the 6.5x55 Swede. Modest speeds in the 2300-2400 range yield extreme penetration with a basic cup and core bullet adequate for moose due to the high SD and low speed. Conversely, your varmint loads use low SD and high MV and give poor penetration as the bullet dumps energy as it disintegrates.
Also, bonded or monolithic bullets can have performance very different from what the SD might predict, usually they behave like higher SD bullets. Generally they are tougher bullets and one should drop down in SD a bit on lighter built game (deer) and save the high SD bonded/monolithic bullets for elk/moose.
This is the best explanation of sectional density l have seen...keep sharing your wealth of knowledge with us! God bless👍
Good info!! What I really like is that this guy doesn't stick to one or two cartridges and say "that's all you need". He gives you the factors you need to consider, what effects them and their effects on your situation and let's you figure out what you want to choose for yourself.
Christmas came early this year Boys and Girls, Every time you post a new video I feel like a kid who just got the Sears Wish Book in the mail. THANK YOU.
I love this video. With the recent ammunition shortages I stocked up on some Sako Superhammerhead 308 win in 180 grains. The muzzle velocity for this bullet is about 2493 fps and I have read people complaining about that online. So much so that Sako seems to have discontinued this particular weight loading but when you take a closer look at the ballistic coefficient (G1=.342) and the sectional density for this bullet you realize it is a superb design for the short to medium distance hunting. As usual the Finns got it right but those of us in America are so fixated on speed that we miss the point entirely. In the arboreal and broad leaf forests of the East Coast of North America you are not likely to be able to get a clean shot at anything beyond 200 yards. Too many trees or brush will be obstructing the line of sight and you won't be able to see the big game until it is about 50-100 yards anyway. I did the calculation and even at 250 yards this bullet/velocity combo still has close to 1500 ft-lbs of energy. The drop is around 4-6 inches which puts it right into the point blank range category when zeroed at 200 yds. The sectional density however is 286 making it a fantastic choice for moose, bear, elk or any other big game you care to go after. I am so glad I purchased this ammo as I now have a sufficient supply for 308 Win for Eastern North America hunting. When I go hunting out west I will take my long range rifles like the 270 win, 7 mm Rem Mag or 300 Win Mag with me but for the East Coast of North America the 308 Win will always be my first choice!
I have as many books written by Jack O’Connor as I could find. I don’t recall him writing about B.C., but it’s interesting how closely his personal experience with different calibers and bullet weights matches what you’ve taught here. Thank you for all of these videos.
Dear sir, your videos are amazing. I love how you tell it like it is and see through all the crap marketing that’s out there these days. Please keep them coming!
Thank you for the deeper knowledge.
Merry Christmas,
You should make a video on your preferences in caliber and weight for each of the game you hunt, or have, with an explanation of your choice. You have so much knowledge to share and are a great teacher
Thank You sir. You make good sense and that is an uncommon trait these days. I look forward to going thru
what you have posted on your channel. I understand the information SD provides, and only when i started to reload
my own brass did i understand it. As soon as i saw .243 the bell went off. Took me 20 years to fully get that with some clarity.
Off the shelf you only get bits of information, selling points i guess you could call it.
You have to respect someone who follows the rules and doesn't remove the big white tag from the lamp cord that says, "Do Not Remove." But you're right, this fellow knows his stuff, and he doesn't blast us with heavy metal in the background.
I like the loading manuals that categorize their ballistic charts based on sectional density. I don’t hunt, but I like the numbers.
Firearm technology genius..Please tell us how Benny is doing? Thank You for sharing your vast amount intellect on firearm technology! You are such a valuable asset us. Merry Christmas to you, and your family..Give Benny a hug for me...
I'm hooked. I just watched 5 of your videos straight. Of course I'll recommend you to others in my family. We're in western sage brush country. As you know momentum actually is defined as mass (M) x velocity (V)...i.e MV. The info on sectional density is great. Thxs for a well presented video.
Thank You Sir! So refreshing to see sound common sense in all your videos! Please continue teaching and making these videos.
As always, the knowledge you impart is greatly appreciated
Dear Sir,
May you and your family enjoy a wonderful upcoming New Year.
Thank you for all of your videos, especially your faith based videos.
Bless you and may God bless your family and Benny.
Best regards,
Rick Mansberger
Excellent video, I hunt with a 44mag rifle with 240gr flat point bullets. I would have to go to 300gr to get into the 240's of Sectional Density. I have shot them before and they act like a hard cast, no expansion & just plow through. I got similar results from the265gr fp they go straight through and the deer run a ways before dropping, with the 240sp the bullet expands and seems to transfer energy into the animal better, I understand that 2 holes are better than 1, but the 240 fp unlike the hp generally penetrate completely, and the deer seem to drop faster than with the 300gr bullets.
I don't care about the foot pounds of energy numbers, I use the Taylor Knock Out numbers, they are more realistic to the killing power and capability's of a given round.
Thanks for taking the time to share your knowledge with the rest of us, keep the videos coming.
Good video. You can get by with less sectional density for deer, maybe even for a long time, but eventually it will be the wrong choice. Part of this topic is the 150 gr. v. 170 gr. 30-30 bullets for deer.
Excellent discussion. Great explanation of a topic that I've been confused about; especially now that I have moved to a part of the country where I'm not making 200 yard shots with my .270 and instead hunting in the woods at much closer ranges. Thank you for this.
The hornady book does an excellent job of showing the SD for every bullet at the top of every page for each caliber.
This guy is a true teacher. Magazines and other print media is full of complicated discussion attempting to always explain what confuses people. However, usually it leads right back to confusion. This is because things are not thought out thoroughly and tested. Media expects us to eat what ever is thrown on to the dinner table. I've heard numerous explanations given to the ballistic debate. And has always been a ping pong discussion. But this fine gentleman here lays it out in good spirits with humility and simple charm. I love his videos. It's like sitt'n down with that uncle mike guy every family has. That guy you approach when all elese has failed and the old world wisdom is what you need. If this guy made his video's around a campfire then it might be a daily watch for me.
Very well said 165 grain bullet and even the 180 grain bullet are the nice weights for 30 cal.
Read the comments and see if you can figure out who the thumbs down is lol.
Good video as usual Blue
This year I used a 129gr 6.5mm bullet and got excellent penetration and terminal performance on whitetail.
If you desire a flatter trajectory, the bullet that fills the bill in the 240 SD is the 120 grain. You don't need the 139 or 140, which is a large game bullet, but too much won't hurt.
Thanks for another very educational video. I have hunted Whitetail Deer for 40 years with everything from .223 to .300 magnums and I don't really know why but over the years. I have found the .270 with a 130grain bullet has simply dispatched the deer faster than anything else. Almost every deer I have killed with it never took a step just flopped down stone dead. I'm in WV btw so most shots have been well under 200 yards.
It's a great round. But physics are universal and unrelated to head stamps. The 130 grain 270 bullet travelling at 3,100 fps would be bettered by a 280 bullet of 140 grains if it struck at identical velocity. Similarly, a 165 grain 30 caliber bullet would better each. All have identical sectional density, but the bullet with greater frontal area will always be more destructive if of the same construction, striking at the same velocity. The 270 advantage is less recoil, and less but sufficient destruction. Most folks shoot the 270 better because they don't flinch as they would with heavier rounds.
Thanks for the video. I'm attending SDI and this explanation has been excellent help in my studies.
EXPERTLY ADDRESSED! THANK YOU AND MERRY CHRISTMAS!
Even with all the technical aspects of this subject, you managed to make it very simple to visualize and comprehend.
Another great video, thanks for sharing your experience!
PS - Merry Christmas and a Happy New Year, hope Benny's doing well!
Merry Christmas! Yes, thanks be to God and all the prayers from his friends, Benny is full of himself, and doing wonderfully.
@@GunBlue490 Glad to hear it.
Thank you for taking the time to make this video. Very good information.
You are the Professor Emeritus of firearms.
How did you make Sectional Density into an enjoyable video? I watched it twice. Cheers!
haha. yep
Most people don’t know all the science behind the guns like this fella . Pretty darn good from the little I knew before I started watching this channel . I ve probably learned the most form this channel . Most importantly to be a good decent person at all times . I am a believer 👍👍
Thankyou Sir! Hope you and yours have a Merry Christmas!
This is soooo Good! Here is a sound basis to make a solid decision. Thank you Mr. GB. You are a legitimate guru of the Internet.
So much wisdom...thanks mate
It's like talking to your grandpa that knows everything about hunting, but dumbs it down for you😂.
Please keep making these videos, they're all great and dont get anywhere near enough views. What do you think about 7x57?
Zachary Estep, Gunblue has a video on the 7x57, you should easily be able to find it, if you search for it :)
Merry Christmas to you Sir an a very happy an healthy new year.
Fascinating. Thanks for sharing and have a very Merry Christmas.
A wealth of knowledge. Thank you sir, really appreciated.
Well said, a man with few words ,gets to the meat of the matter, easy peasy, Thankyou.
Dear GunBlue 490 . Happy new year. I trust you and yours are well.
Excellent information. thank you for this informative video.
Great explanation, you made it simple! Thank you!
Love your videos but if I may make a suggestion concerning video quality. I think a lapel microphone would help tremendously in reducing the reverberation/echo of your voice in such a large open room.
incredible video and info. thankyou
Inertia and penetration. Finally someone who knows the science, I’ve been trying to answer this question for years.
Awesome information.
I am 52 years old and jst learned something new. Wish I new this in my 20s. Thanks. Love yr vedios. Appreciate you ser. God bless. 😁👍🙏🙏
Will be doing some research on my bullets now. 😁👍👍👍🙏🇺🇸🇺🇸🇺🇸
This was great and how I knew it when I was younger. I feel like today with our premium bullets, you have to have a discussion about bullet construction along with this topic. Today’s light Premium bullets have the capability to our penetrate heavy bullets. Example a 308 150gr Barnes, nosler partition or swift A-frame will our penetrate a 180 grain nosler ballistic tip or Sierra gameking or Berger bullet. Premium bullets has changed how we think about SD.
Thank you. That was very informative.
Terrific. Thanks.
Awesome video
Thanks
Thanks Sir, love your down to earth common sense instruction. Learned lots from you, God Bless you and yours , Happy New Years !
Thank you. I watch all you videos and I keep learning new information. 👍
Damn educational to the core! Thank you sir!
Man I love this guy
Merry Christmas to you and yours!!!
Great information, as usual.
Thanks for the video. Can you point me to some sources about .240 being the go to SD for deer, .270 for large elk, and .300 for large/dangerous game?
Excellent as always
Outstanding! Thanks.
Thank you for all of the great knowledge you share with us. Enjoy watching your videos.
Thanks for this video, GunBlue. I'm not all the way through with the video, but you should make sure to include the caveat that your info is for *lead core bullets* as copper monolithics penetrate more even at slightly lower weights. Construction of the bullet is possibly more important than the sectional density.
With your number for S.D., that would preclude any standard .22 caliber bullet for hunting deer size game. I'm not sure how big the deer are where you live, but we have deer down here that weigh a 1/3rd my weight. I don't think I need a .308 for those things... 😑
Wow! Talk about some helpful information. You gave us some very good guidelines to go by. All of my hunting shots are within 100 yards, so I would be well served in a heavy for caliber bullet, to keep velocities down, and sectional density up. What do you recommend for black bear? I'm thinking at least 1200 ft-lbs of energy, sectional density around 160-170, and velocity at least 2500fps. Ive been paying close attention to your recommendations for deer, and elk, but black bear is never really mentioned. So, I'm just placing black bear closer to the "elk" spectrum. Let me know if I'm wrong about this assumption...
Excellent, thanks.
I love your videos! Keep it up!
Another great video! Keep up the good work.
In my opinion, sectional density has a sweet spot around .276 for any type of bullet. Then try to find a bullet around the .276 SD with a good ballistics coefficient BC to support it. A bullet too heavy can be inaccurate and a bullet too light can be inaccurate is what I mean, but if you can find that perfect sectional density and get an aerodynamic structure, you're set. Plus ontop of that find a higher muzzle velocity rifle for the trifecta. I have zero shooting experience, I'm just going off my own research and observation
You sir are a book of knowledge, thanks for sharing
This is a request for a video topic as I couldnt find this in your earlier videos.
I am confused by all kinds of "experts" saying that its OK or NOT OK to dry fire a rimfire/centerfire rifle. (firing the rifle without a round in the chamber)
Can you make a fact based video on the topic?
Best regards
Will add that to my list. You may certainly dry fire most modern firearms, and it's very highly recommended to maintain proficiency. There are exceptions, but they are not the rule. Military and police personnel dry fire as a means of practicing trigger control. It's a very basic part of CMP classes. I wouldn't own a gun that cannot be dry fired. I do it all the time, and it's cheaper than ammo by a long shot.
Hey gunblue490 you should do a video on ackley improved not a lot of people know what it is and it’s very interesting
Thank you!
Thank you Blue and God Bless you and your family. If Force = Mass * Acceleration why isn’t this law used in ballistics? Everything seems to be tied to Velocity = Distance / Time. Of course, gravity is constant and always pulling the bullet down to earth. I am guessing that acceleration quickly become zero and deceleration occurs. Deceleration = Final Velocity - Initial Velocity / time taken. Deceleration is acceleration just in reverse, so Force = mass of bullet * Deceleration. So comparing Force by bullet, seems a way to determine killing power of a bullet.
Very good information
Thanks for bringing up this topic on how important sectional density is in taking down game. Maybe you should bring up the fact the 6.5 Creedmoor 140 grain bullet has a SD of .287. Better than any of the bullets shown on the glass table in the beginning of the video. And my h higher the .240 needed to do the job on deer efficiently. Now we know another reason the 6.5 Creedmoor is so popular. Maybe you can bring that up instead of always talking about your old standbys. Thanks
Could you recommend some reading material on various firearm subjects, or perhaps a video tour of your library?
It depends on the sort of material you are interested in. Most current material is of the black rifle wannabe military variety, which is where the writers have found a home. If you have any particular interest, I will perhaps cover it.
GunBlue490 The modern Rambozo The Clown wannabes is exactly what I am NOT interested in. You have probably forgotten more about firearms than most so called experts of today will ever know. I would be interested in the books you read as a young man when you were building your knowledge base. I can't speak for everyone, but I don't think you have ever made a video that wasn't worth watching. Thank You!
@@thetoecutter13 two words jack o connor
Happy New Year’s!
Question. I bought a lot of 180gr Remington Soft Point cartridges for my .44 magnum revolver. I like them because they are powerful (1537fps 6 inch barrel), and accurate. My intended use for this cartridge is on smaller White Tail Deer at distances of 30 yards and in. I am concerned if I should re-zero for Black Hills 300gr XTP cartridge. A more effecient and highly accurate loading @1150fps. In deference to your knowledge and experience, any thoughts? How do things change with respect to sectional density when it comes to handgun cartridges? Are my 180gr bullets too light?
P.S. I would recommend that Black Hills loading. It produced a sliver dollar size group with all 6 rounds at 25 yards. They also averaged the exact advertised velocity on the chrono. I was impressed!
The shorthand practice of dividing the bullet weight by the squaring the bullet diameter for comparative ratio of SD's is fine for saving you a few steps in the calculation of the "actual" SD. But to calculate the "actual" SD, you'll have to divide the weight by the "actual" cross sectional area that is derived by the square of the radius with the coefficient of pi.
Whatever my length of hand was, it's the commonly accepted definition. Comparisons are made from widely published data that has been around for over 100 years that have become accepted norms. Any further computation is meaningless for the hunter.
@@GunBlue490 Of course, that's why I said it's fine for comparatives. It's just a personal pet peeve when people parrot stuff with no true understanding or knowledge of the subject. Classic examples is calling 45 Colts "Long Colts", calling mono blocks "trunnions" when they have nothing to do with Trunnions, defining "Mills" as milli-radians when in reality they're defined as milli-tangent ratios, or calling an Armory an "Arsenal", and so on.
Ok, I've got a question, I've been hunting most of my life with the 308 150 grain bullet on deer. I've used all the different brands and I've got no complaints. So after watching this i went and looked up the SD on all the bullets that I can remember and none of them have a 240 SD! I've also hunted deer with other calibers successfully and none of them had 24 SDs. Is there something I'm missing?
Another excellent video. Thank you.
Great video. Do you happen to have any references for the SD numbers that you mention? Just curious about how folks decided that "0.240" was enough for deer etc. Thank you and Merry Christmas.
Pure experience of decades. The SD is published by every bullet maker, but you can just get an SD calculator on line, and plug in weight and diameter in inches, such as 165 grain, .308". The SD is common to all brands of the same weight and bullet size.
Wow fantastic video. I learnt alot
Happy New Year! I absolutely love your videos and have learned so much from you.
I am eager to learn your thoughts on the long term storage of ammunition. I do keep some in metal ammo cans but was told I should include some moisture absorbing silica packs. My ammo cans as well as my boxed ammo rests inside of various safes here in my office.
Do you feel there is any issue keeping handgun and rifle ammo in their respective boxes long term? Should it all be kept inside of metal ammo cans? I very much look forward to your thoughts.
Blessings!
Great explanation thank you for taking the time to make this video. How does sectional density recommendations change when using a monolithic bullet? For example a 30 caliber 168 grain has a section of density in the 250s but would likely out penetrate a standard cup and core bullet in the 270s on an elk.
Thank you for your videos.
Does the reduced bearing surface of a VLD type bullet compared to a semi-spitzer flat bottom require a faster twist rate?
Thx
Beautiful !
GunBlue, it depends on the bullet. A Barnes .277 110 gr. TTSX has a SD of .205, it goes through and through on antelope and mule deer with no problem. Farthest shot was 320 yards. I have taken 2 deer and one antelope, all went down as if pole axed using lung shots.
Physics are what they are. They cannot be altered by anecdotal evidence. The fact that your bullet did its job does not prove that a standard bullet of correct density will not, nor that you would be better off with a Barnes of the sectional density I stated. A cross-through lung shot is the ideal that hunters don't always have. A good bullet of the correct sectional density should not be minimal, as there is no need for minimizing such issues as the bullet weight, which I suppose might be for the sake of a few feet per second of velocity. You are referring to a bullet construction issue that is not contradictory of the information I provided. You support what I said about bullet deformation and lead loss. A Barnes bullet does not have lead to wash away and thereby suffer loss of mass, but the fact remains that a bullet of .205 is still not as capable as a PROPERLY CONSTRUCTED bullet of .240 sectional density which does not suffer lead loss. I have frequently stated that I am not here to offer advice on brands of shooting products. Barnes bullets are renown and are good, but so are countless others that do exactly the same job. My classes are intended to offer facts based on physical facts that stand alone apart from brand recognition.
Is there a minimal velocity you'd want to hit at? Ie- 220 gr core lokt .308 bullet out of the 30-06 leaves the muzzle at 2400 ft/sec. SD- 330. I figure 200 yards and in, this would take any animal in North America... Thoughts?
Complexity made simple...
Thank you Sir for the knowledge you pass on. I have been using a .270WSM for about 10 years now. I chose that caliber largely in part to it having the reputation of being a flat shooter at longer distances as compared to my 30-06. After harvesting a couple deer , I decided to not use 130gr ammo and instead began utilizing 150 grain ammunition only. I did so because with 130gr , Deer would go a few yards before collapsing as opposed to the 150gr where deer just went straight down without 1 more step. I understand there are other variables such as shot placement that could account for that. My question to you is , am I to understand that the 130gr is not as effective simply because it is traveling too fast as opposed to the 150gr that is just a bit slower?
I think in a world of lead core bullets using SD for a penetration prediction is a good rule of thumb. However, as a long-time copper monolithic fan, I don't think it holds as true 🤔 with bullets that retain their weight while reliably expanding. I will take a reliably expanding bullet that retains almost all of its weight over a higher sectional density bullet for caliber that sheds its weight and effectively ends up at the same if not lower SD in the end. For example, I have dropped plenty of mule deer on the spot with a .243 and an 80gr barnes that had roughly a .19 sectional density. But that bullet always retains the weight where a 100gr core lok is going to have a better SD but lose weight like a teenage girl with a eating disorder the instant it gets to the animal doing the same amount penetration roughly if not less in my experience.
God, I miss my grandfather...