Here are some pictures of the revolver cylinder. I'm not sure of the brand - maybe someone will recognize it? I found this on the ground several years ago very close to where I found the split .40 case. There are several revolvers out there that can fire .45ACP, but don't think it would be easy to fire a .40 S&W in one of them. Jim, does the Glock leave bright marks on either side of the firing pin dent? I have some .45 cases that I picked up near the .40 - I could take pictures. - Bob