Twist rate for new .308 and cast bullets

[jaysouth]

I have the urge to buy a new rifle. My choice will likely be a Weatherby Vanguard S2 in .308.

A couple of fellow clubmembers have recently purchased Vanguard S2s in 308 and 30-06. They get regular sub moa groups with handloads, with no fiddling, tinkering or bubba modifications.

I am interested in the 308 standard 24" rifle or 20 " carbine. However the .308 only comes with a 1:12" twist barrel.

How large and long a cast bullet will this twist shoot reliably? In the past I had one 12" twist that would shoot 180 RN jacketed RN bullet but not a 180 BTSpitzer.

Any input from rifles you have owned?

Thanks

[pipehand]

Jaysouth, the 1:12 will let you get a bit more velocity from cast. Also, a 180 or even 200 grain cast 30 cal. boolit isn't as long as a jacketed spitzer, and should have no trouble stabilizing. Some of the guys that are having rifles built for shooting cast are using the Palma twist of 1:13 or even 1:14 to optimize velocity and accuracy with cast.

The .308 Winchester made its debut with a 1:12 barrel. As a cost cutting measure, most manufacturers just stock one twist of 30 cal barrel in the 1:10 standard for the 30-06.

I can't tell you what max weight for cast that will stabilize in cast, but 200+ grain 311299's work.

[Kull]

How large and long a cast bullet will this twist shoot reliably?
Thanks

Punch some numbers into a twist rate calculator and see what it says.

http://www.bergerbullets.com/litz/TwistRuleAlt.php