I've been running 250 grain XTP's (.452) in my MLII. They haven't made many tracks, but they do tend to turn inside out and lose the core inside of 50 yards. I suspect that it will cost me an animal someday if I keep using them. I picked up a couple of boxes of 300 grain .458's that are designed for the 45-70. I need to remember to order some sabots cause no one carries them.
