I've fired probably 500 rounds of at least 20 different manufacturer's ammo, and at least 800 rounds of reloads with 2 failure to eject. They were some weaker reloads that I made while working up a load, so I don't count them.
Rifle has been 100% functional using 40gr, 45gr, 50gr, 52gr, 55gr, 62gr, and 70gr bullets. FMJ, Soft points, JHP, spitzers, V-max, steel penetrators. Seems to digest anything. I haven't shot but 20 rounds of steel case Russian ammo (Wolf), but I don't anticipate any problems and just ordered 200 rounds of 62gr JHP Silver Bear from aimsurplus.com
Bummer to hear you got a less than reliable one. I do clean mine after each session at the range (75-125 rounds) and keep it well lubed.