I recently bought a large lot of primers at auction. Included were several 100 LR Magnum primers. Most of my rifle loading is restricted to mid range cast loads in 30 caliber milsurps using 2400 and 4198. Can I use up these primers with these types of loads? I realize magnum primers are normally used with large charges of slow burning powders.
Use for Large Rifle Magnum Primers
- Thread starter Old Ranger
- Start date
Try them with a known good load. They might be better in cases with a lot of air space.
I have found Magnum primers required when using light loads of ball powder under a light bullet. Say, BLC2 in a 8x57 under a 150 gr.
They cure the Click-Bang I otherwise get.
I have found Magnum primers required when using light loads of ball powder under a light bullet. Say, BLC2 in a 8x57 under a 150 gr.
They cure the Click-Bang I otherwise get.
Try 'em. They might end up being better, might be worse , or there might not be any difference.
With your midrange cast loads pressure isn't going to be an issue; with balls to wall loads the difference in pressure amounts to
a grain of powder one way or the other..
With your midrange cast loads pressure isn't going to be an issue; with balls to wall loads the difference in pressure amounts to
a grain of powder one way or the other..
OkayShooter
CGN Ultra frequent flyer
- Location
- Nova Scotia
I recently ran into this. I went to the store and accidentally grabbed small pistol magnum primers. It was advised to back off the load and try again. If you were almost to the max. Now since I was loading below the min, I changed the OAL and made a few test batches.
Was only a 3 FPS difference with no signs of pressure.
Was only a 3 FPS difference with no signs of pressure.
I have used magnum primers with my .270 and I didn't notice any difference in accuracy (didn't chrono that day). Tried with various loads to have a variety of tests - powder load made th only differences in that calibre, in that rifle.
I wouldn't interchange mag primers into a close-to-max load that was worked up using reg LR primers, for that I would back off the load a bit and work it up again.
But I don't think there is any danger using the mag primers on reduced or light loads and it might even work better. I'd do it.
But I don't think there is any danger using the mag primers on reduced or light loads and it might even work better. I'd do it.
Last edited:
- Location
- The Conservative part of Ontario
Sometimes a small change can make a big difference in accuracy. For better or for worse. Maybe you get lucky, and find a 'trick' load out of your mistake. Like others have said here, if you're below max, you can just swap them in no worries. Max loads on the other hand should always be re-worked no matter what you change.
