OK. Lets be logical. In the AR15/M16 family of weapons most failures in a properly maintained rifle can be traced to either the mag or the ammo. Assuming that you have properly lubed the weapon and that all of your mags are serviceable, I would think to look at the SA ammo, which is horrible and never functioned right in my AR, or the PMC, which is a little less than horrible, but not by much. Go to ammoman.com or ammodeal.com or whoever you use and buy some M855/SS109 or some M193. If the weapon, again properly lubed and with good mags, fails to function, then send it back to Bushmaster. I have yet to have had a problem with SS109 or M855 because they are the same thing. The M193 has also never failed me. IMI is pretty cheap out of Claflin cartridge, and has also never failed me. Let us know the results. And never, never, ever use wolf ammo in your AR.