No more arguments or discussions. If you're wondering what twist rate to get your AR in, now you know. Please ignore any previous discussions on the matter; I have gone directly to the experts and compiled their findings and data here. You're welcome and please don't waste another byte of data on the internet asking what twist rate to get.
Why would a longer twist cause more yawing?
Less stabilized. 1/7 over stabilizes 55 grain, but it's required to stabilize heavy tracers like op said. 1/12 *barely* stabilizes 55 grain, which the m16 was designed to shoot, which causes it to tumble like a mother fricker on impact and transfer a shit load of energy.
No. You are wrong. Stop posting.
There is no such thing as "overstabilization".
There is no such thing as "understabilization".
A rotating projectile in flight is either gyroscopically stable, or it isn't.
What a too fast twist rate will do cause excess leading of the barrel (for lead bullets) and in extreme cases will cause bullet jackets and bullets to tear apart in the barrel. What a too slow twist rate is cause instability.
>gives definition for bullet overstabilization... refuses to use shortened phrase for it
>instability is suddenly COMPLETELY DIFFERENT from "under-stabilized"
why are ESLs like this?
You're using made-up words that fail to accurately describe different phenomena in ballistic science. It makes you look like an ignorant fool and you should stop.
>moron just continues to expose his lack of familiarity with English
welcome to the English language, turd worlder
You're only partially correct. The idea of being over or under stabilized applies not only to the flight path, but to the impact. It's very easy to stabilize a bullet in flight, where a little fast or slow doesn't matter. But a 55 grain in a 1/7 will have poor terminal ballistics compared to the same bullet in a 1/12. Therefore, it's commonly said that 1/7 over stabilizes 55 grain. It's not just the flight, it's the impact.
If you're shooting paper then it doesn't matter, otherwise see op. I have 1/7 on my 10.3 and shoot 55 grain because I want a flatter trajectory for paper. I have different guns that I prefer for hunting in larger calibers.
What if you have an 11.5" barrel?
Then you should be using 300 AAC Blackout, 450 Bushmaster, 458 Socom, or even 350 Legend, none of which these twist rates necessarily apply to.
What's the ideal barrel length for 300blk?
Just split the difference with a 1:8.
No. This is stupid. If 1:8 made sense, I would've included it in the list. It's dumb. It won't stabilize tracers or the longest copper solid, and it is inferior to 1:9 for all the other mid weight bullets.
Listen to what I am telling you. It's already been figured out.
A bullet that is less stable in flight, or barely stable, has more of a chance to lose stability and tumble when it impacts a denser medium (flesh etc).
What about 308?
1:10 is ideal for everyone except varmint hunters, who should choose 1:12. 1:10 was originally used for the 30-06 while 308 was originally 1:12. 308 shooters started realizing the benefit of heavier bullets, so most 308 guns today have adopted the 30-06 twist of 1:10. With a 1:10 you can stabilize a 220-grain round nose, even at subsonic velocities.
Noguns alert!
Twist rate debate is only had by people who don’t shoot. I have rifles in 1:7, 1:8, 1:9 and 1:12 and the difference is absolutely negligible. I even hunt different twist rates and can’t say I ever saw any notable difference in wounding.
Barrel length on the other hand is definitely an issue. Twist is for academic debate.
I would love to see you successfully shoot tracers out of your 1:12, or to shoot a 30gr varmint bullets at 3600FPS through a 1:7.
1:7 twist rate 20inch barrel 55gr fmj fragments explosively in ballistic gel and in the human body, that's why it is the standard twist rate for 556. What you want to do is find the max twist for a bullet to stay stable in gelatin while at the same time fragmentation, but that's only possible with enough speed. The higher twist while retaining stability in gelatin has another benefit if it won't fragment, the rotations per minute cause the surrounding tissue to be sheared away essentially ripping it apart as the bullet passes through the muscle tissue, Google 556 bullet wounds. Think of a flat nose 45acp with 1 in 12 twist, all it does is punch a clean hole through a person, but give it a higher twist and it pulls apart the tissue that surrounds it giving a wider cavity.
Incorrect. 1:7 is not the standard twist rate. It was chosen for infantry who have to shoot tracers and probably have a barrel length too short for high velocities to cause issues with slower twists. If you're not shooting tracers or the new high-tech copper stuff, you don't need nor want it. It only makes sense if you have 11 inch barrels and want to shoot heavy shit at lower velocity, which is just what 300 Blackout, 350 Legend, 450 BM and 458 Socom are all much superior at.
I want the bullet to fragment violently in the human body while retaining 14 inches of penetration, that can only work with a 1 in 7 twist 55gr fmj. If I use varmint tip the penetration never exceeds 8 inches.
>14 inches of penetration
Where did you pull this number from and why does it matter?
Ballisfics gel, you want that bullet to pass completely through that person while fragmentating.
Humans aren't made of gelatin.
They are pretty close to it though. If you use a power or screw ar15 for home defense, just use a suppressed glock 21 with flat nose bullets. They always kill animals the quickest