Did/does S&W use the same rifling in barrels for guns chambered in 45 Colt and 45 ACP, or are there any differences - twist, depth of rifling, or groove/bore dimensions?

Both are 1 in 16 twist rate, couldn't say about any of the other segments of this question.

Sir, I don't know about now, but they used to be different. Rifling in .45 Colts was five-groove, while .45 ACP was six-groove and shallower for jacketed bullets. Bore and groove diameters differed, too, but more according to era than chambering.

Hope this helps, and Semper Fi.

Ron H.

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Wishin' don't make it so.

Thanks for the replies and info.

Actually, there are still differences in rifling between most S&W Revolvers and the .45 ACP revolvers. The .45 ACP's still have narrow, six land rifling while S&W's "standard" is five wide lands.

My 625's shoot really well, so I don't consider it a "downer". All my revolvers see is my own cast bullets. I have heard people complain about the "new" barrels but I have shot both of mine and several of my friends' 625 revolvers and they shoot really well (625-6 and 625-8's). I'm talking under 1" at 25 yards.

If you try to shoot commercial soft swaged bullets at elevated velocities, I suppose that could cause a problem, but with my own cast bullets I see NO problem whatsoever with bullets of varying designs.

FWIW
Dale53

I have a 25-5 (un-pinned) that shoots both very well-hard cast LSWC's. Flapjack.

Thanks much for the further info and insights.

I believe where this really shows up is with the older 25-2 vs 25-5 guns. The 25-5 45 Colt had deep rifling and would shoot lead bullets just fine. The 25-2 Model 1955 Targets had shallow rifling, and did not shoot most lead bullets well.

Bob

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