Buffalo Bore Ammunition 19D20 Heavy 357 Magnum 125Gr Handgun Ammo – 20 Rounds – Buffalo Bore’s 357 mag. ammo adds more power than ever before to the 357 mag. This ammo is safe to shoot in ANY all-steel 357 revolver, including J frames. This ammo is no harder on your gun than any other normal 357 ammo. NOTE: This ammo is not recommended to be fired in super light alloy revolvers.