Mark... I’m really glad you covered this subject because the only explanation for the rebated boat-tail bullet was supplied by the manufacturer (Alco)... They are showing great results at 1k yards. .308 175gr .707 (G1) BC driven at 3050fps out of my 300WSM...! Thank you for your technical info...!!!
You never cease to amaze me ! You take complicated answers or reasons and simplify them so much and put them in simple layman’s terms even I understand ! You have an incredible gift for that and you should have at least one million followers/subscribers because no one does it as well as you ! THANK YOU !!!
Very interesting subject. Never really thought about energy loss? by using boat tail vs flat base bullet. But your explanation clearly shows how that could happen. Thanks again sir
I have taken up bullet swaging and Ive been gleaning information about this sort of thing where I can. Interesting point about making the crown match the bullet style, I've never really considered that. A couple points worth mentioning is that any boat tail design (depending on other bullet specifics) may not show any benefit at all over a flat base for as far as 500-600 yards. And also you touched on this a bit, but the use of a flat base bullet can actually reduce throat erosion in chamberings that are known to be "barrel burners". I used to be of the mindset that a boat tail is simply better, but since taking up swaging Ive learned that for many shorter range scenarios a flat base actually has many pluses over a boat tail. Thanks for the video, very informative.
base expansion is like the Diablo form used in pellets in airguns. You can often get better performance with them if you spread the base before loading since they're made of soft lead and get dented in. This pressure seal is what the shot-cups are for in shotguns. Interesting to note that just about all .22lr have a cup-tail that both holds the bullet in the casing AND expands on pressure.
Great Information about RBT bullets. I Just bought corbins swaging tools and I will soon use rebated boat dies to produce some bullets in 6 mm caliber. I'll let you know How things work. Regards Patrice
Mark, Good stuff. I had been seeing some stuff from Rex and a few other ELR people about RBT bullets lately. I remember... however many years ago Corbin was talking up the benefits of RBT bullets, at the time it seemed more like something he was pushing as it was what his tooling was capable of making. Given the amount of experience I've had since then, and lack of anyone else really doing anything with it, I wasn't super convinced to even revisit the idea until recently. After seeing your video, I'm still not sure it's an idea worth revisiting. Maybe when I get some more time. It's interesting recounting the changes we've gone through as far as hunting crowns, to target crowns, to muzzle brakes, to suppressors (at least here in the states, as well as scandinavia). Brakes and suppressors have really made a massive difference both in terms of recoil, and accuracy for so many calibers, I use them even in places that seem silly. Putting a brake on my .22LR does nothing for recoil,, but makes a massive difference i group size.
I agree with all you’ve said, I’ve always viewed rebated BT’s as a potential bandaid to a hardware issue. I also question manufacturing consistency when another shape process is introduced. In an age when we’re using added and accurised processes in hand loading to reduce tolerance variation round to round I’m wary of potential inconsistencies in all consumables.
Very interesting video mark I had never actually heard of a rebate boattail bullet I do see the logic behind it but I also don't see a need for it If a gun is set up and maintained properly Thanks for all your great videos hope you and Sam are having a wonderful summer
crazy as it sounds i use rebated boat tails in my double rifle . They seem to be quite slippery and I get the same velocity from a 168grn rebated boatail as I do from 150 grn fb
Interesting article. It seems to me that the flat based bullets would offer longer barrel life over the boat tails, due to the flat base creating a better gas seal.
I had a 308 Norma magnum that would shoot flat bases bullets more accurately than boat tails ,after checking the bore with air gauges it had tight and loose spots in the bore ,changing to Lapua step boat tails brought the accuracy back with the better trajectory at longer range.the bore variations were minute .
Hi Mark, Thank you for the always informative videos. You mentioned David Tubb. What do you think of the ring that he puts on the tip of a bullet? He claims that it pushes up the BC?
I don't shoot long range and know it's not the norm for jacketed bullets but have you thought about or tried a gas seal on a boat tail? Maybe a bullet shaped like a football with a gas seal? Would that help with the "problem " of pushing the bullet or the point where bullet leaves the crown? Anyway just some thoughts love the vid as always and appreciate what you take the time to tell us about things!
What If The Rebated Boattail Was Machined In Step Down Fashion Then There Would Be Multiple Flat Edges To Push Equal Down The Barrel But As It’s Stepped Down It Would Behave Even More Like The Boattail In Flight Since There Are Several Smaller Square Edges To Produce Less Drag Instead Of One ?? Mark 😀 Great Video and Subject
Doesn't work. Remember, bullets spin at about half a million RPM, and travel well past the speed of sound. I have no doubt golfballs acquire quite a spin, just much less than a bullet, and don't travel at supersonic velocities for very long. Because of the rotational speed, dimpling doesn't work, but sometimes having rotated features that mimic dimpling can have an effect. Usually you see this in hypercavitation based projectiles, which is a whole different topic.
It is such amazing time, when we can get such high quality, well presented information for free. Excellent work with all of your high quality content.
Cheers Mika
Your illustrations along with the explanations aid immensely in understanding. Thanks.
Thanks Mike, Cheers
Been learning heaps from you Mark and Sam, thank you so much!
Thanks Man, cheers
Got it. Good insight from a guy who is not just behind a desk or in some lab. Great Video.
Thanks
I want to thank you folks for the educational experience. When I watch your videos I feel enlightened and not confused. Keep it going...
Thanks Vernon
I've been in the shooting sports, and a student of guns and ammo, for over 50 years. Yet, I've learned so much from you!
Awesome, Cheers
You make extending one knowledge easy to understand and very entertaining
Thanks Colin, Cheers
Mark... I’m really glad you covered this subject because the only explanation for the rebated boat-tail bullet was supplied by the manufacturer (Alco)... They are showing great results at 1k yards. .308 175gr .707 (G1) BC driven at 3050fps out of my 300WSM...!
Thank you for your technical info...!!!
Thanks Tommy
I"m really happy to se your blogs get so many views so quickly. Almost at the 100K
Thanks Bor, yes getting there, Cheers man.
You never cease to amaze me ! You take complicated answers or reasons and simplify them so much and put them in simple layman’s terms even I understand ! You have an incredible gift for that and you should have at least one million followers/subscribers because no one does it as well as you ! THANK YOU !!!
Your welcome, glad you liked, Cheers
honestly that's probably the best explanation of it I've ever heard
Thanks Allen, Cheers
Very interesting subject. Never really thought about energy loss? by using boat tail vs flat base bullet. But your explanation clearly shows how that could happen. Thanks again sir
Thanks Brian
I have taken up bullet swaging and Ive been gleaning information about this sort of thing where I can. Interesting point about making the crown match the bullet style, I've never really considered that. A couple points worth mentioning is that any boat tail design (depending on other bullet specifics) may not show any benefit at all over a flat base for as far as 500-600 yards. And also you touched on this a bit, but the use of a flat base bullet can actually reduce throat erosion in chamberings that are known to be "barrel burners". I used to be of the mindset that a boat tail is simply better, but since taking up swaging Ive learned that for many shorter range scenarios a flat base actually has many pluses over a boat tail. Thanks for the video, very informative.
Cheers
How the hell do they not have millions of views? Extremely great content coming from this channel. Was just introduced to it today.
Thanks Jonathan, Cheers
Lots of science, great info. Cheers!
Thanks Mike
Interesting , there is always a trade off
In any bullet shape
Very informative video thx 🙏
Cheers Islamdo
Thanks Mark you always do a good job of explaining a topic👍
Thanks Joe
base expansion is like the Diablo form used in pellets in airguns. You can often get better performance with them if you spread the base before loading since they're made of soft lead and get dented in. This pressure seal is what the shot-cups are for in shotguns. Interesting to note that just about all .22lr have a cup-tail that both holds the bullet in the casing AND expands on pressure.
Thanks Man, cheers
I enjoy learning some new information about bullet ballistics
Cheers man
Corbin Bullet swaging is a big proponent of rebated boattail bullets.
Yep, thanks Man, Cheers
mate, your videos are fantastic. I love the engineering content, and the discussions of the reason why X does what it does.
Thanks Terry, Cheers
Great Information about RBT bullets.
I Just bought corbins swaging tools and I will soon use rebated boat dies to produce some bullets in 6 mm caliber.
I'll let you know How things work.
Regards
Patrice
Awesome, Cheers
Love your stuff Mark. Very informative as usual.
Thanks Man, Cheers
Terrific explanation. Great graphics. I really appreciate your work.
Thank you, cheers
Thanks Mark. Another interesting presentation.
Cheers Dave
Great information as always. Your views are very well thought out!
Thanks Rich
Very good video. You're a good teacher I just learned something About Bullets I do a lot of reloading.
Thanks Steve, Cheers
Thanks Mark.
Cheers
Mark, Good stuff. I had been seeing some stuff from Rex and a few other ELR people about RBT bullets lately. I remember... however many years ago Corbin was talking up the benefits of RBT bullets, at the time it seemed more like something he was pushing as it was what his tooling was capable of making.
Given the amount of experience I've had since then, and lack of anyone else really doing anything with it, I wasn't super convinced to even revisit the idea until recently. After seeing your video, I'm still not sure it's an idea worth revisiting. Maybe when I get some more time.
It's interesting recounting the changes we've gone through as far as hunting crowns, to target crowns, to muzzle brakes, to suppressors (at least here in the states, as well as scandinavia). Brakes and suppressors have really made a massive difference both in terms of recoil, and accuracy for so many calibers, I use them even in places that seem silly. Putting a brake on my .22LR does nothing for recoil,, but makes a massive difference i group size.
Thanks Drew, glad you liked, Cheers
a keep it simple stupid very understandable explanation Mark
thankyou
Thanks folks
I agree with all you’ve said, I’ve always viewed rebated BT’s as a potential bandaid to a hardware issue.
I also question manufacturing consistency when another shape process is introduced.
In an age when we’re using added and accurised processes in hand loading to reduce tolerance variation round to round I’m wary of potential inconsistencies in all consumables.
Cheers Tony, thanks
Very interesting video mark I had never actually heard of a rebate boattail bullet I do see the logic behind it but I also don't see a need for it If a gun is set up and maintained properly Thanks for all your great videos hope you and Sam are having a wonderful summer
Thanks Matt, and winter here, lol, glad you liked, Cheers
crazy as it sounds i use rebated boat tails in my double rifle . They seem to be quite slippery and I get the same velocity from a 168grn rebated boatail as I do from 150 grn fb
Cheers
Love your videos mate, keep them up.
Thanks Andrew
I’ve never used them. Any issues with catching on case mouth during seating? Good info. 👍🏻
same as flat base, Cheers
Interesting article. It seems to me that the flat based bullets would offer longer barrel life over the boat tails, due to the flat base creating a better gas seal.
Cheers
RWS used to make their TIG and TUG bullet designs that had full 90 degree cone shaped bases that terminated in a sharp point.
Thanks Ken, Cheers
Thanks for sharing your insite.
Cheers
I had a 308 Norma magnum that would shoot flat bases bullets more accurately than boat tails ,after checking the bore with air gauges it had tight and loose spots in the bore ,changing to Lapua step boat tails brought the accuracy back with the better trajectory at longer range.the bore variations were minute .
As mentioned, probably about the crown rather than the bore, Cheers
Every time you put up a vid I learn something thanks mate take care and stay safe both of you cheers Yogi 🤙🤙
Awesome, thanks Yogi, Cheers
Very good in depth explanation as always 👍
Thanks George
always excellent info. thank you
Cheers
Thank you for the great information.
cheers West, thanks
Great presentation as always Mate 👍
Cheers man. thanks
Thank you very much for the video material, sorry Russian subtitles don't work...I'll review it again with a translator
🤝👍👍👍
Thanks Man, Cheers
Great video Mark, very informative 👍
thanks Man
Hope you and sam are doing well, thank you for the content
Cheers Man, thanks
The rebated boat tail is the lapua d46. Scenars are normal boat tails.
Cheers
Great stuff again. Cheers.
Cheers Man
Very intersting. Thanks
Cheers Walter
Great information, thanks.
Thanks Mark
Hi Mark,
Thank you for the always informative videos. You mentioned David Tubb. What do you think of the ring that he puts on the tip of a bullet? He claims that it pushes up the BC?
Not what he said, he found it give a more consistent but lower bc on his projectiles.... Cheers
As always, excellent!
Thanks
The LAPUA D-46 185 gr .30 caliber bullet is rebated and still holds competition world records from the 1930's
Cheers
Great content thanks for sharing
Cheers
I can assure you , It's allot easier to swage a RBT than a BT... And it's easier to make the swage dies as well
Yes I gather, Thanks Adam, Cheers
I don't shoot long range and know it's not the norm for jacketed bullets but have you thought about or tried a gas seal on a boat tail? Maybe a bullet shaped like a football with a gas seal? Would that help with the "problem " of pushing the bullet or the point where bullet leaves the crown? Anyway just some thoughts love the vid as always and appreciate what you take the time to tell us about things!
Thanks Mater, and well, all explained in the video, but no that wouldn't help, lol, Cheers
well I learnt something. I would guess driving bands are good when you're chasing muzzle velocity.
Cheers
What If The Rebated Boattail Was Machined In Step Down Fashion Then There Would Be Multiple Flat Edges To Push Equal Down The Barrel But As It’s Stepped Down It Would Behave Even More Like The Boattail In Flight Since There Are Several Smaller Square Edges To Produce Less Drag Instead Of One ?? Mark 😀 Great Video and Subject
All explained in the end of the video, thanks Chris, Cheers
How does a muzzle break change the gas coming behind the bullet?
We have videos on that, Cheers
Thanks !
Cheers
Given your years of shooting and videos here on youtube, I'm sure you've experimented with the DTAC bullets. What is your experience with those?
They are a decent bullet, Cheers
Mark has anyone experimented with dimpling a bullet, like a golf ball to lower drag?
Doesn't work. Remember, bullets spin at about half a million RPM, and travel well past the speed of sound. I have no doubt golfballs acquire quite a spin, just much less than a bullet, and don't travel at supersonic velocities for very long. Because of the rotational speed, dimpling doesn't work, but sometimes having rotated features that mimic dimpling can have an effect. Usually you see this in hypercavitation based projectiles, which is a whole different topic.
60000rpm to 300000rpm
thanks dude!
Cheers
Mark, it appears to me that Lapua was trying to imitate the original. 408 CheyTac bullet. Your thoughts?
We have used and like the later Cheytac 350grn 375cal, but not seen the early designs, Cheers
You need NASA to put those bullets into a super sonic wind tunnel to see what the flow and local pressures are.
Lol, Cheers
Where practice trumps theory (evidence based is the current go word)
Lol, Cheers
弾頭〜👍💡🎶🎵⭕
Thanks
😧😧😧😧😧
Cheers