OK, a 357 SIG is just a .40 cal S&W necked down to 9mm. I wonder what kind of velocities you could get if you necked down a 10mm to 9mm? Would it actually approach or exceed a .357 Magnum?

Quote from: gandog56 on July 12 2017 10:57:30 AM MDT
OK, a 357 SIG is just a .40 cal S&W necked down to 9mm. I wonder what kind of velocities you could get if you necked down a 10mm to 9mm? Would it actually approach or exceed a .357 Magnum?

Pretty sure you would get 9X25 Dillon velocities, since that is what a 9X25 Dillon is.   

Quote from: gandog56 on July 12 2017 10:57:30 AM MDT
OK, a 357 SIG is just a .40 cal S&W necked down to 9mm. I wonder what kind of velocities you could get if you necked down a 10mm to 9mm? Would it actually approach or exceed a .357 Magnum?

http://10mm-firearms.com/wildcats/357-sig-long-neck/


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Quote from: gandog56 on July 12 2017 10:57:30 AM MDT
OK, a 357 SIG is just a .40 cal S&W necked down to 9mm. I wonder what kind of velocities you could get if you necked down a 10mm to 9mm? Would it actually approach or exceed a .357 Magnum?

A 357 SIG is 23mm and a 40 S&W is 22mm, the 357 SIG round came from the 10mm.

Then why are the no longer than my .40 cal S&W's? I use the same magazines for both when I swap out the different caliber barrels for my SIG P229.

Brass length is not COAL length.