I think it was a .45. In another video he states that he uses the G21 and his friend the G20. Plus in the elk video the Glock has a funky rear sight and in the video below he states it's his G21, it's got the funky rear sight also. He replied to a comment left by a viewer that he used a FMJ on the Elk for penetration but has started using Grizzly +P ammo, and they don't offer a +P 10mm. I think Mr. Warren should upgrade to the .45 Super
Here's the video:
"There is a principle which is a bar against all information, which is a proof against all argument, and which cannot fail to keep a man in everlasting ignorance – that principle is condemnation before investigation."