I went to the range today to try out my 20 inch heavy barrel upper I just got off of an trade. It's a model one upper with BCG being model one also. When i first got it I noticed how loose the bolt fit in the carrier. I didn't think too much of it until today at the range when i had a straight pull bolt action instead of a semi auto AR15 . I've double checked the gas system and everything is lined up and gas tube isn't blocked. Could this be gas rings that are too small? When i got home I took them off the bolt and spread the gaps a little and i can tell the bolt is acually sealing in the carrier now... Is this a common problem? Any ideas and or advice would be greatly appreciated.