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Re: AR barrel twist Q...
You'll be really pushing it on that, but why not give it a try? I've heard crazier working, but at the same time I'd only invest a box or two into the test.
You'll be really pushing it on that, but why not give it a try? I've heard crazier working, but at the same time I'd only invest a box or two into the test.
Re: AR barrel twist Q...
The problem I believe then becomes "over-spinning". Since you can push a 50gr a lot faster than a 69-80gr then it is spinning faster. Lets say your 50gr is going 3400fps in a 1-7 barrel it will be spinning at 351,724 rpm. That is enough to cause some bullits to come apart. I have heard stories of a puff of dust about 3-10 ft from the muzzle. by contrast a 70gr going 2900fps would be spinning at 300,000 (more than I thought). Needed for the longer bullit thought.
A 50gr going 3400fps in a 1:10 barrel would be 244,800rpm
The problem I believe then becomes "over-spinning". Since you can push a 50gr a lot faster than a 69-80gr then it is spinning faster. Lets say your 50gr is going 3400fps in a 1-7 barrel it will be spinning at 351,724 rpm. That is enough to cause some bullits to come apart. I have heard stories of a puff of dust about 3-10 ft from the muzzle. by contrast a 70gr going 2900fps would be spinning at 300,000 (more than I thought). Needed for the longer bullit thought.
A 50gr going 3400fps in a 1:10 barrel would be 244,800rpm
Re: AR barrel twist Q...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">You'll be really pushing it on that, but why not give it a try? I've heard crazier working, but at the same time I'd only invest a box or two into the test. </div></div>I was going through my ammo last night and found an un-opened case of these 50g HP's and was wondering if I should hang on to them or just get rid of them.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">You'll be really pushing it on that, but why not give it a try? I've heard crazier working, but at the same time I'd only invest a box or two into the test. </div></div>I was going through my ammo last night and found an un-opened case of these 50g HP's and was wondering if I should hang on to them or just get rid of them.
Re: AR barrel twist Q...
It will really depend on three things, how fast you push them, how think their jacket is, and how sharp your rifling is.
I've seen 20" 1:7 guns shoot the 40gr fine, but I have also seen shorter 1:7 guns have near muzzle bullet fragment issues on the same ammo, the edges of the rifling on the 20" guns where just smoother from wear and did not do as much jacket deformation depsite the higher velocity.
It will really depend on three things, how fast you push them, how think their jacket is, and how sharp your rifling is.
I've seen 20" 1:7 guns shoot the 40gr fine, but I have also seen shorter 1:7 guns have near muzzle bullet fragment issues on the same ammo, the edges of the rifling on the 20" guns where just smoother from wear and did not do as much jacket deformation depsite the higher velocity.
Re: AR barrel twist Q...
Not all 50gr ammo is created equally either. Jacket thickness varies between manufacturers and lots so there is no definite answer to whether or not it will spin them apart besides "try and see".
Not all 50gr ammo is created equally either. Jacket thickness varies between manufacturers and lots so there is no definite answer to whether or not it will spin them apart besides "try and see".
Re: AR barrel twist Q...
I did not mean to imply that it couldn't be done, and the only true way to know is to try it. I was just trying to explain what a faster spin could do and why all guns don't just have a fast spin. No free lunch here.
I did not mean to imply that it couldn't be done, and the only true way to know is to try it. I was just trying to explain what a faster spin could do and why all guns don't just have a fast spin. No free lunch here.
Re: AR barrel twist Q...
I've shot tons of 52gr HP out of my 1:7 and didn't have any problems. The only problems I've ever seen is with the 40ish grain varmint rounds with really thin jackets.
I've shot tons of 52gr HP out of my 1:7 and didn't have any problems. The only problems I've ever seen is with the 40ish grain varmint rounds with really thin jackets.
Re: AR barrel twist Q...
Yes. One of my favorite and most accurate loads uses the 52 gr hornady bthp. They will be quite stabilized.
As others have mentioned it might tear itself apart due to the rotational forces imparted by the fast twist but unless its a really ask bullet or a really high velocity I doubt it. With a 16 inch barrel I don't thing you would quite hit that kind of velocity from a factory loaded round.
How far? My guess is until it tears apart(close to the muzzle), approaches the trans sonic region or hits something.
Yes. One of my favorite and most accurate loads uses the 52 gr hornady bthp. They will be quite stabilized.
As others have mentioned it might tear itself apart due to the rotational forces imparted by the fast twist but unless its a really ask bullet or a really high velocity I doubt it. With a 16 inch barrel I don't thing you would quite hit that kind of velocity from a factory loaded round.
How far? My guess is until it tears apart(close to the muzzle), approaches the trans sonic region or hits something.
Re: AR barrel twist Q...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: steelcomp</div><div class="ubbcode-body">I know as a rule the faster twist barrels are for the longer bullets, so this is a more specific question...will a 7 twist 16" AR stabalize a 50g BTHP? If so, for how far? Ammo is Federal .223 50g JHP.
TIA </div></div>
how far? until it goes subsonic. once its stable it will generally remain so up to the subsonic mark and then spin like a ninja star. depending on muzzle velocity thatll prolly be around 600 ish if i had to guess with no further info.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: steelcomp</div><div class="ubbcode-body">I know as a rule the faster twist barrels are for the longer bullets, so this is a more specific question...will a 7 twist 16" AR stabalize a 50g BTHP? If so, for how far? Ammo is Federal .223 50g JHP.
TIA </div></div>
how far? until it goes subsonic. once its stable it will generally remain so up to the subsonic mark and then spin like a ninja star. depending on muzzle velocity thatll prolly be around 600 ish if i had to guess with no further info.
Re: AR barrel twist Q...
Thanks for all the replys everyone. I'll keep the ammo and see how it shoots. I don't imagine the Federal bullets are exceedingly fast or cheap enough to come apart. Sounds like I should be OK.
I'll get out in the next week or si and come back with the results just for conversation sake. It's always good to have another point on the plot.
Thanks for all the replys everyone. I'll keep the ammo and see how it shoots. I don't imagine the Federal bullets are exceedingly fast or cheap enough to come apart. Sounds like I should be OK.
I'll get out in the next week or si and come back with the results just for conversation sake. It's always good to have another point on the plot.
