Vintage Remington primers id

[car16]

I have a thousand large Remington primers that I am trying to id. This is what it looks like I think it is large rifle .I would appreciate any info thx 267101

[JimB..]

I thought that 72M were the primers originally used for 5.56. There were things in the formulation that caused slow cycling and so they were abandoned.

If you’ve got large primers I’m not sure what you’ve got.

[car16]

It was written on the outside of the sleeve of 1000 lp but they will not seat flush so I thought lr

[relics6165]

car16:

I found this:

Colt's Inc., first experienced difficulty in 1963 in complying with the 6,000-round endurance test for the Air Force contract. Specifically, the problem was defined by Colt's as an excessive accumulation of fouling on the bolt assembly. This fouling resulted in sluggish operation, which in turn, lead to failures to feed and eject. Frankford Arsenal was assigned the task of investigating the problem and determining to what extent the trouble was attributable to the ammunition used. In the course of the investigation, it was determined that these rifle lots which failed the endurance test were those firing Remington ammunition and using a Remington 72M Primer, which contains lead styphrate, barium nitrate, tetracene, antimony sulfide, and calcium silicide. Those rifle lots that passed the endurance test had fired ammunition using a Remington 92 Primer, which differed from the 72M Primer in that it did not contain antimony sulfide and calcium silicide.

I bet the 72M refers the primer composition, and not the primer size, much like the old Frankford Arsenal FA70 primer. The FA70 was the old military standard, corrosive, but with an incredible shelf life in all kinds of conditions, and the go to primer until the 1950s. The FA70 designation was the primer mixture, not the size.

I bet this is the same situation here, careful measurement should indicate if this is a LR or LP.

[car16]

I appreciate the information I looked on the internet and found nothing I think they are lr because I tried to put in 45 ACP and it didn't want to seat flush. They had been wet at some point and dried but still went off.

[car16]

Are they non corrosive or corrosive

[Texas by God]

Remington Customer Service might have an answer. 1-800-243-9700 is their phone number. Worth a shot- sorry for the pun.....

[relics6165]

car16:

These are from the early AR15 age, they would be non corrosive.
Are they non corrosive or corrosive

[Winger Ed.]

Are they non corrosive or corrosive

Corrosive primers went away in the mid-ish 50's.

[car16]

Thanks for all the information