September 29, 2009, 09:48 AM | #1 |
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Location: Texas
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Magnum Primers?
I am relatively new to reloading and since it has become quite difficult to get reloading supplies I have a question relative to primers. I stocked up a while back on primers and when I did I went ahead and bought some magnum primers for two of my rifles. I have not reloaded much for them because I am deer hunting with rifles that are not magnums so I have barely touched the Magnum primers. I am running low on Large Rifle primers and have not found them to be in stock any where so my question is what would happen if I used Large Rifle Magnum primers when I run out of Large Rifle primers in rifles that are not magnum rifles?
Also if I can finally find some large rifle primers that are not the ones that I used working up my loads how much would they affect my groups? Thanks, |
September 29, 2009, 10:02 AM | #2 |
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You can use magnum rifle primers in a non-magnum rifle. As a general rule of thumb, if you change one component you need to back down to the start charge and work your way back up. Don't just slap in a different primer, especially if you are at or near a max charge. This is especially true if moving from a non-magnum to a magnum primer. Doing so can increase pressures by thousands of PSI which can move a safe load into dangerous territory.
Good luck. |
September 29, 2009, 11:44 AM | #3 |
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Magnum primers are fine in standard cases, especially for loads that don't fill the case completely, where they can actually improve ignition consistency and start pressure. My rule of thumb is to back a load down 5% when switching to a magnum primer, then working back up. I use a chronograph to compare before and after and just increment the reduced load until the velocity matches what I had from the original standard primer load. If you don't have a chronograph to compare your old and new loads, see if you can borrow one at the range?
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September 30, 2009, 07:46 AM | #4 |
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Location: Texas
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OK then, - I decided to switch from standard large rifle to match grades - any cautionary advice? My loads are all pretty much middle of the road.
Last edited by kenjs1; September 30, 2009 at 01:41 PM. |
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