Large rifle magnum primers in .308 m1a 16?

[just bill]

I have started reloading for the M1a 16 SOCOM, all I could find was large rifle magnum primers. In other posts I found that if using magnum primers instead of regular ones, cut the powder back 10%. Any thoughts? There were those that said not to worry, others said cut back. I think that was for target pistols. Never reloaded for bottle neck cases before.
Thanks,
Bill

[winelover]

I occasionally use CCI LR magnum primers, depends on the powder. Slow powders tend to call for magnum primers. AA 4350 comes to mind. There are others. Check the reloading manuals.

If your shooting reduced cast loads, no need to download by 10%...........say you have developed a load you like. Might want to try a magnum primer. May or may not tighten up that group. Just be smart about it.

In a M1A, you should be using military type primers, like CCI#34, because of the type of firing pin it has. Reducing the chance of slam fires. My Armalite AR-10 doesn't suffer from that issue.

Winelover

[Fireball 57]

Springfield M1A's are pressure sensitive, therefore slow powders ie: 4350's are verboten! Bullets heavier than 175 gr. put a strain on op rods. Will your barrel stabilize those long 180*grainer J-words ? It won't handle a constant diet of 180* loads. Have a nice day.

[Winger Ed.]

Get your powder & bullet situation figured out, and magnum primers will do fine.
My go-to LR primers are Winchester.
The label even says the are for standard or Magnum loads.

My favorites are GI pulls of 147FMJ and 150 spire points with WIN748 in a rack grade Springfield M1A.
I don't shoot long range or at big critters, so I start at around 85% of what the books say,
and tinker around a little from there to get the best accuracy.

If its a concern:
The firing pin hits with way more than enough power to set off any LR primer you'll find on the market.

[HumptyDumpty]

About a year ago, I accidentally loaded a thousand or so rounds of .308 with magnum primers. I didn't figure it out until I had shot most of them, and went back to my supply closet for another box of primers. Now this was through a PTR-91, but there was no difference that I could perceive. Fired a few through my FR-8 as well. 147 grain projectiles, surplus pull-down powder (WC-842). I don't recall the exact charge; it's buried in my notes somewhere.

[Lloyd Smale]

i sometimes use them for ball powders in 308s but never stick.