Rebel_Rider1969
Well Known Nuisance
Seeing 3 types, 1:10, 1:9.85, 1:16.
Glock 9mm g26.
What's the best twist? For 115, 124 or lighter.
Glock 9mm g26.
What's the best twist? For 115, 124 or lighter.
Using a 1.35 inch long .308 bullet (173 gr) and crunching the numbers we get about 10.5 (One turn in 10.5", which is pretty close to the 1:10 twist normally used in .30-06 rifles. The twist for the .308 is nominally 1:12 because it was based on the shorter bullet of the 150 gr military ammunition from which the .308 commercial round was developed. Most match rifles in .308 have a 1:10 twist to stabilize the 180 and 190 boat tailed match bullets better. The results from the Greenhill formula are on the conservative side--indicating a faster twist than probably needed. That doesn't cause any problems because a little too much stabilization is better than too little.T = Twist in inches
K = Greenhill's constant = 150 (This has to do with the specific gravity of a jacketed lead bullet)
D = Bullet diameter in inches
L = Bullet length in inches
T = (K * D2) / L
It's bullet LENGTH NOT WEIGHT that determines twist, but , unless you want to change barrels ?? and spend $$$$ "run what you brung "Seeing 3 types, 1:10, 1:9.85, 1:16.
Glock 9mm g26.
What's the best twist? For 115, 124 or lighter.
Building a G26 upper. Was wondering about why there was so many different twist rates on 9mm. Also more reading reveals 1:24 is used. Wow.It's bullet LENGTH NOT WEIGHT that determines twist, but , unless you want to change barrels ?? and spend $$$$ "run what you brung "
Probably use bits or poly propellers.I myself would go for the one offering the max RPMs if you plan to rum hollowpoints. Only because they act like a blender once the claws open up. What the max is for that bullet type in a tiny pistol is tho I dunno.
It's a shame Envirude don't make a ammo ;-)Probably use bits or poly propellers.
I'd be really interested in your results with the two different twist rate barrels in the same gun. Keep us posted!Bought a 1:10 threaded one too.
The factory barrel is 1:985. So 3 to play with. The two aftermarket ones are rated for lead. 5r.I'd be really interested in your results with the two different twist rate barrels in the same gun. Keep us posted!