09-26-2019, 10:45 AM
I like lapping uppers. In my experience it makes swapping optics much easier. I bought a lapping tool because of a radical upper, I had to adjust the rear sight all the way to one side to get sighted in properly. Tore it down lapped it, reassembled, and when I sighted it back in the rear sight was sitting right in the middle like normal. This is an extremely case(maybe).

