BTW, the factory picatinny mount sucks--way too bulky and it sits too high above the bore, in my opinion. I forget who it was, but a forum member also mentioned the problems associated with the factory mount causing the shroud to clock, so I went with the Allchin mount, which is very nicely finished and very low profile.
The only thing is that I really wasn't too sure about switching over to red dots at first, so I didn't use locktite when putting this together. So far it hasn't given me any problems so sooner or later I'll tear it down and remount with locktite, or maybe not? If it's still working properly over the next 500-1000 rounds I'm not about to mess with success.