HSM Cowboy Action centerfire rifle ammunition is meticulously engineered for authentic target shooting applications. Loaded with 240 gr Round Nose Flat Point projectiles, these rounds achieve a muzzle velocity of 1325 ft/s and a muzzle energy of 936 ft lbs. Utilizing premium brass casing material, this ammunition is built to deliver uniform pressure retention, consistent downrange performance, and smooth mechanical cycling in vintage and modern firearms alike. Caliber 38-55 Win, 20 rounds per box. Safety Note Always prioritize safe firearm handling protocols and verify that your specific firearm is rated for modern centerfire ammunition before use.