TOTAL Newb here so any help is greatly appreciated!! Had about 3-5 jams, several w/failure to load at different angles in the chamber and one that made it IMPOSSIBLE to get the bolt back. Needed RSO to butt slam it. I used 2 different Magpul mags and was only loading 3-6 rounds at a time. All full metal jacket target ammo. This was only the 2nd day using my APOC upper/PSA lower at an indoor range. day 1 put about 100 rounds through it, no issues. Day 2 (jam day) put about 200 rounds through it with jams occurring at ~150 and beyond. Ammo that jammed was American Eagle. Winchester didn’t seem to cause a problem. I believe that the 5.56 was the one that jammed not the .223. Upper is chambered in 5.56. Inspection of the BCG and chamber didn’t reveal anything to my newb eyes.
Unfortunately I didn’t think to inspect the cartridges or bullets. I did reload them post jam and they fired without a problem??
Thanks in advance.