Buffalo Bore Ammunition 11C20 Heavy 38-55 Winchester 255Gr Rifle Ammo - 20 Rounds - This powerful rifle ammunition is manufactured with exacting standards with the gun owner in mind. Buffalo Bore produces strictly big bore ammo with massive firepower and dramatic results. Popular calibers include: 45-70 Magnum Lever gun,heavy .444 Marlin, Heavy 38-55 Winchester,Heavy 348 Winchester,50 Alaskan, Heavy 35 Remington, Sniper 223 Remington, Sniper 308 Winchester, Heavy 450 Marlin, Heavy 30/30.