I shot the original X Bullet through my Savage 10 Tactical (puts some age on the rifle in perspective....) and it shot fine. The "new" TSX is similar but with more driving band cuts. I wouldn't be surprised if they didn't suck from a semi-auto since you have to load to magazine length instead of being able to load to the lands.
The good news is that there are plenty of other good bullets to try to get the performance you want.