As far as I know I was compressing it enough. I pushed it down as far as the mmp sabot. The primer was going off, pushing the bullet/sabot15 inches up the barrel. Id push the bullet sabot back down over the charge & try again, same thing, bullet/sabot would go 14-15 inches up the barrel. did that 3 or 4 times. I had a good shooting combo with the mmps. So I gave up with the CRs. The bore on my X7 was real tight when I got it last year . After 100 fireings or so Its loosened up. The first 8-9 inches is real tight, then it loosens up.