Twist Rate/Ammo Discussion

I shoot mostly 55gr out of my 1:7 and I can't tell shit.

>>34562991
Ive shot 62gr green tips out of a 1/9 without a problem up to 200m too

Someone talk shit to us and tell us why we are wrong

>>34562977
1 in 8 is better than both

>>34562977
>How bad is it to fire a 50gr out of a 1/7?
Not bad.
>At what range will you notice the downsides?
None.

Overstabilization is a myth.

twist rates for .223 rifles are mostly bogus internet nonsense

I have yet to see a 1:7 rifle that tumbles 50gr projectiles and a 1:9 rifle that fucks up 75gr projectiles

most twist rate calculations only apply to voluminous .30 caliber cartridges or bigger

>>34563725
>most twist rate calculations only apply to voluminous .30 caliber cartridges or bigger
Don't make shit up.

>>34562977
>how bad 55 in 1:7
Accuracy may not be great but it will be perfectly acceptable for range/combat use and it's safe.
>77gr in 1:9
Depending on WHICH 77gr it may be phenomenal or it may not do great, but it will be safe. Look up the dimensions of whichever bullet you will be shooting and plug them in to Berger's stability calculator.

Your assumption is correct. Twist rate has FAR FAR less impact than the manufacturers/barfcom/arg/your viet vet druggie granduncle claim.

>>34563361
Not a myth. Just very hard to do because it IS vastly overblown by the "muh milspec" crowd.

Try shooting 36gr Varmint Grenades in a 1:7. The bullet will literally fly apart in the muzzle device.

>>34564209
All right, it's a myth up until the point that your bullets start to disintegrate. I'm honestly surprised that's possible at all, but then I've never shot 36gr anything.

>>34564233
There are very real, very measurable negatives to shooting light bullets through tight twists. Sometimes these cause accuracy issues before bullets start disintegrating, sometimes they dont.

Whether these negatives matter to YOU is your decision.

>>34564260
>There are very real, very measurable negatives to shooting light bullets through tight twists.
Then surely you'll expand upon them.

>>34564307
Eh, I'm bored so I guess I'll spoonfeed you.

>Fast twist barrels produce less velocity than slow twist barrels, all else being equal
More energy goes in to spinning the bullet, leaving less to push it forward. Plus friction increases. Your standard 55gr M193 will shoot around 130fps faster through a 20"1:12 barrel than through a 20" 1:7 barrel. The difference grows as the barrels get longer.

>fast twist barrels experience leade and throat erosion faster
Increased friction and pressure produces potentially vastly accelerated wear. I can't find any well done scientific testing but it seems like all the hobbyist ballisticians at 6mmbr.com and all the jewtubers seem to agree 1:9 barrels last around 15% longer than 1:7 barrels of same or similar quality.
>marginally stable bullets are more accurate
Figure your stability scale goes from 0 to infinity, with a bullet with a stability of less than 1.0 tumbling as it leaves the muzzle, and a bullet with a stability of 1.0 or higher NOT tumbling as it leaves the muzzle.

Stability is not a constant, velocity changes it. A bullet travelling, say, 3000fps may be stable at 230rps. Slow it down to 2000fps (like at 300 yards) and now it needs 320rps to be stable.

This is where things like the Berger calculator recommend stability of 1.5 to 3.0--it gives margin of error for different velocities without giving up a bunch of velocity. But your known distance shooters are trying for twist rates that produce stability factors of 1.05 to 1.2. They don't need the safety net because they are shooting known distance. They have found these barely stable bullets shoot better.

>>34564101
proof me wrong then

>>34565239
Spend a few minutes playing with this.

http://www.bergerbullets.com/twist-rate-calculator/