Our 38-55 ammo is designed to function in all 38-55 chambered firearms built with modern metallurgy for smokeless powder. It operates at 38,000 CUP—comparable to the 30-30 Winchester, which has an average max pressure of 38,500 CUP. For reference, the 30-30 case is simply a necked-down version of the 38-55 casing.
Our 38-55 Works in All Winchester 375 Rifles
This ammo is also compatible with ALL 375 Winchester chambered rifles. That includes models from Winchester, Savage, and Marlin. All 375 Winchester rifles have chambers long enough to accept the 2.085-inch 38-55 brass, even though standard 375 Winchester brass measures only 2.020 inches.
By using the longer 38-55 brass, we achieve two key advantages:
- The bullet seats closer to the rifling, resulting in generally more accurate loads.
- The thinner case walls of the 38-55 brass increase case capacity, which significantly reduces chamber pressure.
In effect, our 38-55 loads deliver the same performance—a 250gr. bullet at 2000 fps—as the original 375 Winchester loading, but at only 38,000 CUP instead of the original 52,000 CUP industry max pressure.
