EthanYXH

I encountered the same issue. I purchased a brand new M4 today and took it to the range. I fired 150 shots, and it jammed four times. The same issue occurs as above: shells are not loaded into the bore, and it is hard to get the shell out as well. I wonder how Vandal Bee solved this issue. When I purchased this from the shop, the staff repeatedly pushed the bolt back and forth at least 15 times after applying some gun oil, to lubricate it. Does that malfunction have to do with unprofessional maintenance? How did you guys solve this issue? @Vandal Bee