View Full Version : Caliber velocity in different pistol brands

06-14-2009, 7:08 PM
I'm trying to find out if different brands of pistol would have different velocities for the exact same ammo (brand and caliber).

For example, would the exact same .45 caliber round have a different velocity in a Glock Model 21 than it would in a Smith & Wesson Model 4566?

Thanks in advance for any assistance.

06-14-2009, 8:05 PM
i believe all that would be a factor into the velocity of a round would be the length of the barrel

06-14-2009, 8:17 PM
Possilby tolerances of the gun could make a difference? A barrel with different rifling could have more or less friction which may make a slight difference. Don't know for sure, but a thought.

Action would make a difference too. If propellant gas is being used to cycle the action, the velocity would be a little bit less.

06-14-2009, 8:26 PM
I suspect it would be so minor a difference as to make no real difference. Load your own and you can dial in a wide range of velocity (power factors). Big differences in powder and levels, moly coated bullets or not...even the brand of primers will make a difference.

06-14-2009, 8:39 PM
Polygonal rifling creates higher velocities in the same barrel length. How much, I don't know.

06-14-2009, 10:11 PM
Very small differences depending on the barrel (length, rifling, etc).

Probably no more then a few feet per second.

06-14-2009, 10:31 PM
Blow-by, barrel/bullet friction, barrel length, rifling design/rate-of-twist.