On the 3rd mission and just now upgrading the pistol. After upgrading the first time, the pistol texture never loads. I've tried everything but no matter what I do, it stays the same and its detail never shows up. Is this a known bug? I've tried searching but nothing has come up. Playing on 360. Thanks.

Same thing happened to me. The next time I loaded and played the game the correct texture was in place.

Interesting. I've tried that too...didn't work for me.