I have a customer who has an old S&W revolver chambered for 38 S&W. I can not find ammo for it, but found 38 Long Colt. Can these be safely fired in 38 S&W gun? From cartridge dimensions it appears this would be possible, but not vice versa.
The even-shorter .38 Short Colt cartridge (still made) can be fired in a .38 S&W chamber, but the bullet (and case) is a little undersized in diameter.
Just on the principal of it, while the .38 Short Colt case is a few thousandths on an inch smaller in diameter than .38 S&W, the proper .38 Short Colt bullet is a heel base one with a nominal diameter of .375", hardly smaller that the .38 S&W bullet at a nominal .361", +.000"/-.006" (SAAMI specification).
2152hq,
While you are correct about the .38 S&W and .38 New Police being basically identical, what possible good does that do the OP when the .38 NP has not been manufactured since at least the 1960s?
Yes, they were funny about that back in those days. Marlin did the same thing with the .32-20, marketing the .32-20-100 Marlin cartridge from c. 1900 until c. 1915. The only difference between it and the .32 W.C.F. was the bullet weight and shape.Colt not wanting to put the competitors name on their product in the way of a caliber marking just re-named the caliber,,changing the projectile profile a touch.