First, Thanks so much to all here who take their time to share their experience. This forum is truly a wealth of information for those who take the time to look for it.
I couldn't find any reference to what I am experiencing, so here goes.
I'm struggling to keep a build extracting & ejecting properly. I'm wondering if this might have any effect on proper ejection.
When inserting a loaded magazine with the bolt locked back, I am seeing the front edge of the bolt catch pressing down on the rim of the top cartridge which causes that round to pivot up to the point it will not chamber by releasing the bolt. The pic shows an empty brass in this position. I was trying to reproduce this inside and didn't want to be fooling with a live round. The result with a live round is the same whether factory or my reloads.
I get the same result with a Stoner (Midway) 450BM magazine, or a metal 20rd Colt mag with single follower inserted.
I get the same result when switching lowers as well.
The only way I have found to avoid this is to make sure the top round is pushed slightly forward in the magazine when it's inserted.
Is this just to be expected, or will adjustment of the magazines be required ??
Thanks again for your input.