Big bolt guns, from the looks of the pictures on his web site. He's got hunting and tactical versions, as well as supressed ones. "80% of a 50 BMG in a 14 pound rifle" I believe. I've been thinking about a 500 A2 in a Ruger #1H for some time now, mainly for cast bullet shooting. His versions sure looks like nearly the same thing, but throated for BMG bullets.