ORIGINAL: burntmuch
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.
I use the CR with .458 bullets in my Savage, and they are "just right tight" with a dirty bore. I have used them with .452 and .451 and some Parker Ballistic Extremes (.450) and had the same result as you, no fire. That is with a good igniting powder, so I know the CR are pretty loose in most guns with .452 bullets.
Chap