Is it okay to use magnum small pistol primers in .223 reloads?

[Dan Sierpina]

Sheesh, now you guys have me kind of concerned. I just loaded up 1000 with Federal Small Rifle Match Primers. I know that Federal's Match grade pistol primers are way softer cups than regular Winchester cups. Should I worry about these Match Rifle primers being soft? I've yet to shoot any through my AR...but that will all change next week. I'll try and update with the results.

Federal 205M primers have been the preferred primer of benchrest shooters for years. Hot loads are the norm in those bolt guns. They should be just fine in the AR.

[Anonymous]

So my setup is a Sig Sauer M400 with BFSiii binary trigger, RTB lightweight BCG and RCA adjustable gas key with medium buffer spring.  I have about around 100 .223 loads using 26 grains of IMR 4064, 55 v max, and small pistol magnum primers.  Every one has fired, cycled, and chambered flawlessly without slam firing.  When switched to binary, it also runs flawlessly.  Bolt locks back to the rear after last round.  I strongly recommend doing what I did if you are going to try it out.  Load and fire one round in a mag.  Drop mag, shotgun ar15 and remove bolt (or just take bolt out if using bolt action).  Check down barrel for squib (bullet in barrel).  If clear, repeat five times.  Once confident that bullet is firing and exiting the barrel, do two shots to ensure correct function.  Keep testing, slowly building up how many rounds you're firing until you feel confident it is completely functioning properly.  I have not been able to chrono the round but recoil feels the same as a regular load.  Take it for what it's worth.  Haven't tried it with any other powders but so far so good.  

Edited August 6, 2020 by Anonymous
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