Help - Anyone know with 100% certainty as to what primer the M118LR round uses?

[TheGerman]

I have 1500 never fired M118LR pulled down brass with the primers still in them. This is from the lot that was available about 2 years ago of M118LR cases that were at one time loaded, but then had the bullets/powder pulled (no idea why) and the brass case with primer became available. It still has the sealant in the inside neck area that needs to be removed with mineral spirits.

Was trying to figure out what primer it was as I wanted to load these and do a load workup, but without knowing the primer, duplicating any good load combinations is useless as I won't have the primer component correct.

Anyone know for certain?

 

[JMGlasgow]

Probably CCI #34 primers. These are considered magnum primers.

 

[sirhrmechanic]

Can't say with 100 percent accuracy. But from what I have:

First M118 was with a military primer number 43, same as the 30-06. This was for .308 c. 1963.

In 1976, Lake city changed primers to the standard primer for all other .308... and that was the No. 34 Military Primer also designated No. 36 (not sure the difference.) At the time they made this change, they moved to using standard GI brass, but this caused some problems with the ammo. Likely more due to the brass than the primer, but who can say.

Last designation was M118 Special Ball done for the USMC. Not sure the date. This used an un-punched and (according to sources) No 43 primer (no staking marks around the edges.)

Interestingly, I can't find references to the No. 43 primer as any kind of current commercial offering.

But the CCI 41 primer appears to be the closest on the market.

Hope this didn't fuzzify the muddification too much.

BTW I have some M118LR primed like you have, bought on SH. My plan is to load them up as though they have a standard CCI LR primer in them... nothing too hot. Shoot them as plinking rounds, thereby fire-forming them. And then reload with a known primer and fireformed to my Sako chamber.

Cheers,

Sirhr

 

[JMGlasgow]

CCI41 primers are small rifle.