It went on fairly easy, i heard stories of it not lining up and people having to turn it another 3/4 turn to get it to line up right, i didnt have this proplem. I had to go about another 1/2 turn and it lined up right. so i took it off and put some red loctite on the threads and screwed it back on. then i had to take a dremel and grind down about a 1/16th off the shaft cause it stuck through the barrel, i was a little hesitent but it turned out awsome, beats having to pay a gunsmith. if you do get it you will probably have to do the same thing, its not that big of a deal to do..... just take your time and use a slow speed. i didnt use a washer, hence why i had to grind some off i just didnt think it would look right. and its about the same hight as the brass bead, i can look down and sight mine fine with my picatinny rail on there. if you want grs look at the psi sights, they are expensive but also the only ones i know that use a picatinny rail for the rear sight and they have an option for a barrel clamp mount for the front. Thats what im saving for anyway.