In the spirit of modesty I can't really claim to be King of tightass, but I'm certainly in the royal family. My latest immaterial issue to obsess about is the hammer ding that's appeared on my lower. I didn't know how the thing worked, and found out the hard way that the only thing stopping that hammer at the end of it's throw is aluminum. For those who come after me: when you takedown the XCR, cock it and put it on safe. Then, when you separate the upper from the lower, the hammer won't bang down. Don't dry fire the gun without obtaining the services of a small child whose hand can fit between the hammer and your precious lower. Give him some candy or something when it's all over.