Buffalo Bore Ammunition Buffalo-Barnes Lead-Free Heavy 357 Mag 140 Gr Bar. It is the typical barn-burning turbo-charged Buffalo Bore type of heavy 357 Magnum load and should only be used in all steel revolvers. It does not have the case capacity to use a bulky flash retarded powder thus there is noticeable muzzle flash with this load except when firing it from the rifle which yielded little to no flash. NOTE: It should not be fired in revolvers with a light weight alloy frame or cylinder. Specifications for Buffalo Bore Ammunition 19K/20 Buffalo-Barnes Lead-Free Heavy 357 Mag 140 Gr Bar: Manufacturer: Buffalo Bore Ammunition Caliber: .357 Magnum Number of Rounds: 20 Bullet Type: Jacketed Hollow Point (JHP) Bullet Weight: 140 grain Cartridge Case Material: Brass Muzzle Velocity: 1550 ft/s Application: Protection Primer Style: Centerfire What is Buffalo Bore Ammunition 19K/20 Buffalo-Barnes Lead-Free Heavy 357 Mag 140 Gr Bar good for? The manufacturer says that it is best for protection.