I recently bought a Tennessee Guns Bulgarian AK-74. The first time I took it to the range, I was pretty happy with it. I had a round get stuck in the chamber, but I just whacked the charging handle with a hammer and it popped out. I don't think I had any failures to eject, and I put about 250 rounds through it. The next time I went to the range, I couldn't seem to get more than 2-5 rounds through it before I would get the empty brass jammed into the chamber with the new round or an empty brass sticking out of the ejection port. Every once in a while we could tear through a mag without a problem, but most of the time it was a grind. We still managed to get about 500 rounds through it. I rotated my mags (mostly surplus) in such a way so I'm pretty sure they aren't the issue, and I had problems when using Hornady, TulAmmo, and Russian surplus ammo. I couldn't figure out what the issue was. When I got home and pulled it out to clean it, I noticed the little lever that holds the gas tube on was flipped up and the gas tube was able to move around. I don't know if I didn't put it back right after cleaning it or it came up while firing or as I was pulling it out of the case. Could that have been it, or was it most likely something else? the extractor seems fine and "springy" and I can't find any obvious problems with the individual parts of the gun. Any help is appreciated.