Having my new Garmin chronograph, I'm starting to test my chosen factory ammo in the gun(s) I intend them for. In this test, I wanted to see how the Remington .357 Mag 180gr SJHP ammo performed out of my Marlin Cowboy rifle. The Marlin Cowboy has a 24" barrel. My hope was that I would be getting some great performance and screaming velocity. My only knowledge up until now with this video, where the guy tested this ammo in a 16" Rossi rifle. He got 1,563 fps from a single shot, so I was hoping I was going to see higher velocity from the 24" barrel. Of course, that might not be true if the powder completely burned inside the barrel.
Here are the results from five shots:
Here are the results from five shots:
- 1,498.8 fps
- 1,548.3 fps
- 1,549.1 fps
- 1,512.4 fps
- 1,523.1 fps
- 1,525 fps average, with an energy of 930 foot pounds
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