08-12-2012, 05:24 PM
Theoretically, the heavier bullets for a Grendel a 1-8 twist recommended and with the lighter bullets the 1-9 twist is recommended.
Ref:
http://www.varminthunters.com/tech/barreltwist.html
Ref:
http://www.varminthunters.com/tech/barreltwist.html
