I replaced my rail, all is good there. Now I'm having an issue where the bolt isn't wanting to lock back consistently, and it seems to be due to friction.
I have done the bolt mod and it was working fine for months before this mishap. I re-angled the bolt and bolt stop with a file, and smoothed the bottom side of the bolt where the top of the bolt catch glides against it prior to locking the bolt back. I also gave the buffer tube two rotations out to give the bolt more room when it goes back.
This is what gets me. I can pull back on the bolt all day with the charging handle and an empty mag, and no matter how I do it (slow, fast, letting it go right as I do it), the bolt locks back. However, while I'm doing this, I notice that the bolt doesn't go back as easily as it used to, or as easy as it will when the mag has BB's or isn't in place. It even sounds like it is grinding somewhere very lightly, but I don't see marks or paint missing anywhere unusual on the bolt catch, buffer tube, hammer, bolt, charging handle, or receiver.
Edit: Think I solved this with a combo of things - stretching the magazine springs out for more pressure against the bolt lock actuation assembly, lubing of the receiver interior and exterior of the bolt, and bending the bolt catch arm down even more than it was before.
Edited by Nitemare, 25 August 2013 - 11:50 AM.