I just bought a HK tactical USP .45 so I could mount a knight suppressor on it. Well, the second day I shot it I didn't tighten the can down at all so first round.. BOOM!. The can went flying and landed 8 feet down the range. I've never more embarrassed in my life. My question to you guys is did I damage the pistol or the suppressor. After that incident, it seemed my groups went from 1 moa at 30 feet to maybe a little more. I was shaken up for awhile after that then started to get angry at being so irresponsible.