just put a romanain G together and when the bolt is pulled back it jumps out of the rails at the rear where it is put in thr receiver. this is my third build and all is well with the first two. receivers are nodak prem and everything looks the same as first ones,rear trunion same place, same gap between front of trunion and start of rails, it must be a simple fix but i can't see it. the kit is as new all matching. jumps out on left side.