The 300 grain Barnes Expander MZ bullets are really long because they are all copper (which is much less dense than lead), and because of the huge, very deep, hollow point. If you have a 1:28" twist and the bullets show signs they aren't being stabilized, you could try a heavier powder charge to drive the bullet faster. You would probably also get great results with the 250 grain version. I use the 300 grain E-MZ in my Savage, which has a very fast (for a muzzleloader) 1:24" twist, so it stabilizes the big Barnes great and gives very good accuracy. I've not tried the 250 gr version in the Savage, but I do know that I never get as good of accuracy any time I've shot bullets less than 300 grain in the gun. I think that it's because the twist is way to fast at 2200 fps.

Mike