Anybody have a clue to the twist of a Win M70 Pre-64 220 Swift factory barrel (1950's vintage)? I am thinking it was 1:14 but I'm not sure. Would it stabilise a 63gr bullet?

Thanks

pete

The first Winchester rifles that were chambered for the 220 Swift and released in August of 1935 had a rifling twist rate of 1 turn in 16 inches, this was later changed to 1 turn in 14 inches.

I don't know when it was changed to 1 in 14 inches. My 1949 has a 1 in 14 inch twist. I haven't tryed 63 g bullets, mine likes 50-55. It shuld stabilize a 63.