I don't have any technical experience with the .378/50 (Mach V). But I do have some practical experience, and boy is it a hoot to shoot. 10 rounds is a good days work!!!!! And that's with muzzle brake.
Mach V let me shoot his Mach V last summer in South Dakota and that is one powerful round.
[ 01-01-2004: Message edited by: Lee in OH ]