barrel twist

[daniellybbert]

what is the optimame twist for a 250-300 grain .338 alot of barrel makers make a 10 inch twist but if shooting a heavy bullet im wondering if a 9 inch would stablize it better or would it over spin it
what do the guys shooting the .338 lapua have for a twist rate

 

[dan belisle]

A 1-10 in the 338 Lapua should be good up to 300 gr bullets, a 1-9 would help with some of the custom 325, 335 weights. My Lapua has the 1-10 twist, works fine with 300 gr bullets. I don't think you can "overstabilise" a bullet. - dan

 

[roberti11]

Twist rate and stability

http://www.nfa.ca/cfj-archive/ballistics/bullet-stability-calculator-ms-excel-.html

This link points to an excellent spread sheet on the National Firearms Website, the formulas in this are based on and equation derived by C.E.Harris. The formula of C.E.Harris is used by Sierrra and was recently quoted in an article in Handloader mag. This spread sheet allows you to calculate theoretical stability for a given twist, bullet length, wt, bullet dia. and velocity. It is a great place to start.