Friend has an early POF with predator forearm rail.   First time out he had FTF, bolt override, problem with mag being stuck.  Was using rem UMC  ammo.  Was at loss at first to figure out issue.  Suggested trying a different buffer and spring, which he did as he was thinking about selling the upper.    So a H2 buffer and and blue spring from springco was used, now it runs flawlessly, no problems what so ever, using the UMC ammo and different mags.  He used e-lander, lancer and magpul with out a hitch.   Also used some German MEN 556 ammo.

This thing is ejecting consistently at 2 o'clock, have read that ejection should be at 4 o'clock, any comments appreciated.

Looks like it's running.

What's the question?