if you think about it,a two groove barrel,is something like 80?% at .303 of an inch sized hole...so a .308 sized projectile gets 5 thou grip over 80% of its surface....
if you think about it,a two groove barrel,is something like 80?% at .303 of an inch sized hole...so a .308 sized projectile gets 5 thou grip over 80% of its surface....
Bookmarks