Well, I shot 200 rounds yesterday and the only problem was one that may not be related to the ammo. Hopefully someone experienced can comment on this:
First round of a 30 rd mag, I hit the bolt catch and the bolt doesn't slide all the way forward, I look in the side and can see the tip of the round stopped at the forward end of the right hand feed ramp. I hit the forward assist (not real hard) and it slides into the chamber. Problem did not repeat that day.
RRA car a2 mid, D&H mag w/ magpul follower.

My guess is that the full mag was holding a bunch of spring tension on the top round and it gave too much resistance as the bolt tried to strip it out.
Does this sound right?