GAP 10 Mag release

Its definitely the bolt release lever/ left side. The small half on the bottom that catches and holds bolt open flew out along with spring and spring end. The top section (paddle) is still held in by the pin.
 
Thats what i figured, i had the same thing happen on a ar-10t that had a fairly low " <1000 " rd ct. The replacement part armalite sent me was beefier . With the suppressor and the particular load might be gettin a little overgassed and bolt carrier may be gettin a bounce back + spring return pressure and hammerin the tab a little hard on return forward would be my guess