Bbl. twist ?

[Baddog 0302]

Doing some internet searching I came up with , the Marine Corps used a 1-12 twist up to the m40's through the Mk 5 or 6. And the Army used a 1-11.25 on all their M 24's.
1-12 twist Bbl's seam to be easier to find. What are you'll using ?

V/r

 

[Random Guy]

The USMC switched to a 1/10 twist barrel on the M40A6, which has a shorter 20" barrel (as opposed to 24" used on the earlier rifles) and I think that quicker twist rate might stabilize the 175 bullets better with the shorter length. To answer your question: the 'ideal' twist rate is somewhat dependent on bullet weight and barrel length. (ie, a 155 grain bullet might prefer a different twist rate compared to a 175 or 185 grain match bullet)

 

[Baddog 0302]

Thank you, yes the M40A6 has the "catch all" 1-10 twist, I'm guessing the 20" vs 24" came about more for easier handling in urban environments and the faster twist was because of the velocity loss going from 24" to 20" with the M118LR ammo. No doubt in my Marine Corps oriented civilian mind that the armorers at Quantico did a lot of testing.
For me, it's a toss up,one range goes to 300 and another one goes to 600, 1000 if I want to build a portable bench. And, several of my old USMC shooting buddies have gone to help guard the streets of heaven, and I have inherited several shit pots full of 175's, pulled 118 LR's along with 168's and 155's.
Thank you

Semper Fi