The Cowboy bullets at only 12 BHN aren't made to be pushed too hard so I would try to keep the pressures reasonable. For full powder/pressure .357 Magnum ammo I would have bought their 140gr .357 Zinger bullets instead.
BUT, that doesn't mean you can't use the bullets you bought. If the fit is good that's most important. Since we can't measure pressures we have to go by velocity and I'm sure you can push those bullets to 1000 fps without leading.
I would start with 11.0gr to 12.0gr 2400 to start and see how it goes and then move up slowly to maybe 15.0gr depending upon if you're getting any leading or not.
NOTE: Never trust anyone on the Internet for load data. Make sure to double check for yourself. Don't forget the range report...
April 18, 2013, 10:31 AM
Thanks fellas. That Cowboy 14 was literally the only MO bullet available at Graf at the time, so I gotta make the best of it. Will look in the future for the Zingers for sure.
April 18, 2013, 11:16 AM
For more reference-
April 18, 2013, 11:26 AM
Hey Iron, there will be a wait but if you don't mind waiting, order directly from Missouri. More selection than the vendors will have. Top notch company btw.
I think the bullets you've listed will be better suited at 38 special velocities. Unique would be best out of your choices for that cartridge.
April 18, 2013, 02:56 PM
I agree with slowfuse. Those are better for 38 special velocity. I load MBC 38 Match bullets (12 BHN) with 3.4gr of bullseye. This runs around 675 fps from a 2" or 800 fps from a 6". Unique or 231 would work well too. I've loaded some up to 38 spec +P using 4.9gr of unique. Ran 775 fps from 2", 930 from 6". Unique is a good choice for these bullets.
If going for 357 mag velocities, expect some leading. Unique or 2400 drive them well.
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