Fouling is a definite
I was introduced to a rifle builder/gunsmith Alex Wheeler who explained about bumping shoulders. For awhile l was convinced that .002 was the way to go. Inconsistent groups. One trip after fouling, it was there, the magic group, but there after not. Then l followed the advice of Wheeler, stripped bolt, ejector, extractor and firing pin assembly. .004 bump with bolt drop on its own. Bullet centers the throat, no influence from case. Last three trips consistent 3 shot 1/2 inch groups at 100 yards. Sun MOA 200.
What, exactly, in the context of good/bad group size, is the relationship between a fouled bore and bumping shoulders?
