[Copper]

Just as a side note if nobody hasn't mentioned it yet, you can use Glock 22 magazines in a Glock 31. My buddy carries a Glock 31 on duty, and he says that it will be the only caliber he will ever carry. I don't know the ballistics on it, but it tore the crap out of a block of clay we had aquired.

"Anybody worth shooting, is worth shooting twice. Ammo is cheap, life is expensive."
-Rules for gunfighting.