All that comes to mind when I read the "600gr" and 58cal is OUCH. It is all that I can do to tolerate the 50 cal and 54 cal front stuffers that I have been shooting. Of coarse things would be different if I didn't have several herniated discs and the two shoulder surgeries. Good luck to you man, I could only wish to be able to shoot one of those and not wince in the pain that it would cause me lol. [:@] Yeah, I am a bit envious.