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Item 4B (300gr. JFN) is designed for super deep penetration at revolver speeds but will mushroom and penetrate less deeply at rifle speeds. At handgun velocities, you can expect approximately 3 feet of penetration in muscle and bone. At rifle velocities, expect roughly 2 feet of penetration.
At handgun speeds, this bullet behaves similarly to Item 4A in living tissue. The higher velocities produced by longer rifle barrels cause the bullet to mushroom, creating a larger diameter wound channel. However, the increased frontal area of the mushroomed bullet reduces penetration depth.
Below are velocity measurements from over-the-counter revolvers and rifles:
- 1,330 fps – Ruger Super Blackhawk, 6-inch barrel
- 1,334 fps – Ruger Redhawk, 5.5-inch barrel
- 1,770 fps – 1894 Marlin, 18.5-inch barrel
Item 4B is recommended for use in all steel revolvers and rifles currently on the market. It is NOT suitable for scandium or aluminum alloy revolvers.
