The new Barnes Expander-MZ represents the first truly revolutionary projectile for muzzleloaders. It is the first non-lead projectile designed specifically for use in muzzleloading rifles. This new bullet will open up at impact velocities as low as 1000 fps and will retain virtually all of its weight when impacting at speeds over 1900 fps. Barnes is able to use the same technology to make this bullet that they use in making the centerfire rifle bullets. Tolerances are dramatically tighter than that of lead bullets. Available in either.45, .50 or .54 caliber. Package of 10.