Originally Posted by 7MMXBOLT

By crimping you are changing the pressures within the case from the non-crimped rounds which inturn will change your POI. If you had run them over a chronograph you probably would have notice a change in velocity, though not much. Even though you only shot 5 rounds, to me, your target shows your rifle doesn't like it when you crimp that bullet.

Originally Posted by Pawildman

I don't believe you need to crimp the 7mm mag. The ONLY loads I crimp are my 45-70 and handgun loads. I don"t even crimp my 338 Win Mags. Set your die for no crimp. Have you established an off the lands depth for bullet seating? If not, I would recommend 0.020 to start. The Hornady unit which measures off the ojive is a good one.

Different types of bullets have different ojives, and measuring from the bullet tips, especially on lead-tipped bullets gives unreliable results. The bullet ojive is the point that the bullet stikes the riflling. This measurement is useful in determining proper bullet seating depth, but the whole thing is also compromised by your total magazine length. You best not seat bullets with a total COL longer than your magazine will tolerate, or you will end up with a single-shot gun.... one in the chamber and the rest in your hand. Been there, done that.

Don't wanta make it too hard for ya, but it's something you need to learn to deal with....