Military Ammunition Crimping 9mm and 5.56

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Bucksnort1

New member
1. I am finding non-military .223 brass with what looks like sealed primers (purple coloring around primer). Two headstamps are PSD and Wolf. Are these primers also crimped?

2. Does tdhe military require 9mm primers to be crimped?
 
Military crimping was started between the World Wars to stop primers from popping out in full auto weapons and falling into the guns and jamming them. So the short answer is that any military ammo used in full-auto weapons will have crimped primers.
 
I would add a little bit to the "primers popping out", it wasn't concern over blown primers "popping out" (which, while rare, can happen) but concern over the primers of (primarily rifle) ammunition used by machine guns, particularly belt fed.

The ammo in a belt is subjected to a lot of vibration as the belt is fed through the gun, and while I don't know of any specific instances, it's quite likely some where, some time, rounds were found with primers that had been shaken loose or out.

Crimping cures this. And I think its quite likely that the military just adopted a single standard (primers will be crimped) for all small arms ammo production or purchases.

Ammo made with the expectation of military sales will meet the required specs for crimp and sealant. Ammo made for everyone may not.
 
Yes NATO stamped 9mm are crimped . I have thousands of 9mm NATO cases ( WCC-11 & 12 ) they both look to have crimped primer pockets but the 12’s did not need swaging but the 11’s sure did .
 
I have thousands of 9mm NATO cases ( WCC-11 & 12 ) they both look to have crimped primer pockets but the 12’s did not need swaging but the 11’s sure did .
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I had a different experience. I bought a case (10 boxes of 50 rounds) of Winchester White Box 124gn FMJ "Nato" and they were not crimped - reloading them was business as usual. I don't remember the headstamp and they're packed up in a warehouse right now, but I think they are WCC, followed by the year, of course. I bought these around 2014. Maybe '13.
 
All Winchester white box brass I've bought have been stamped Winchester but that really isn't many in the grand scheme of things . I always thought all NATO stamped brass had crimped primer pockets ?

The crazy thing is that these didn't need swaging and that is a crimp ring for sure haha . It may be that the crimp is so far off center is didn't distort the brass into the pocket .
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I don't know about primers falling out of ammo in a machinegun belt. Given that the military drop-tests ammunition, I'm having a hard time imagining machine-gun belts treat it more roughly than that, but never say never. On page 74 of his 1948 Book of the Garand, Hatcher refers to:

…the adoption by Frankford Arsenal of a crimped-in primer for small arms ammunition to prevent falling out of the primers in some machine-gun actions which had a tendency to blown primers and to stoppages on that account…
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I am not clear why, but decapped small primer pockets' crimps seem to have less brass left over the lip of the pocket than the large primer pockets do. As a result, being able to seat a new primer into the formerly-crimped small primer pocket without swaging or cutting away the crimp is not unusual. I've experienced loading a batch of once-fired LC 5.56 cases that I'd set aside and forgot to swage. I did about 100 and only had enough resistance problems with two of them to remind me of what I had forgotten to do. Even though you can do this, I would still swage or chamfer recapped small primer pockets, as it is theoretically possible to force some brass burr metal down into the pocket under the rim of the cup and prevent full primer seating. I don't recall having that problem, personally, but I wanted to throw the possibility out there as a caution.
 
Metal God,

You bring up an interesting point about crimp rings. I have never loaded any cases of any caliber where crimp removal was necessary so pardon my ignorance here.

I have been under the impression crimps on 5.56/.223 cases are three small nipples, if you will, around the primer pocket. You mention ring. Are these cases crimped with a ring or other method?

I found some PSD and Wolf cases that have no military markings on the head stamp but do have the purple primer sealer. I decapped a few and see what appears to be a ring inside the pocket just below the rim. Is this the crimp? It looks like it completely lines the inside of the pocket.
 
Bucksnort,

Lake City uses ring crimps. I believe they are impressed by a flat rod with a recess in the center to avoid firing the primer. A lot of others use staked crimps like you are describing. Below is a Lake City 30-06 round with ring crimp and an HXP 30-06 round with 3-point staked crimp. Both are made to military M2 Ball spec. So it's the maker and not the cartridge that determines which crimp style is used.
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UN , yeah I considered swaging those WCC-12 cases but primed a few , then a few more and now I’m at about 700 of 1500 primed with out needing swaging . The more I load the less I’m worried about but have to say every time I load those cases I have concerns at first but it goes away after about 30 primed . I’ll add that I have had a few (10 or less ) that were hard to prime and maybe one I could not prime . Not to bad and worth taking the chance cus I remember cutting out all those WCC-11’s out . Not fun , way to small a case for big sausage fingers . 223/308 no problem but those 9mm cases are a pain ( literally) for me .

As to ring/circle crimp vs staked crimps . I have both staked and ring crimped cases that are both marked NATO .
 
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I'll add that I'm in a bit of a unique situation . Our range has military renting out some of our ranges all the time . This means I can easily get same head stamp including year LC and WCC cases . When the military leaves after shooting they leave behind thousands of cases each time they come . This results in not only us getting same headstamp cases in large lots . Those cases are likely all from the same cans pulled from the same pallets in storage that were shipped from the same ammo plant . Point being , I likely have a better chance then most to actually have once fired cases that all came from the same plant and maybe even the same machine . Point being is that it’s likely if I pick up 1k cases , if a few cases don’t need something then they will likely be the same . I see this a lot with the NATO brass I get ftom our range . Well that's something I want to believe anyway . ;):D
 
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Unclenick.

I bet 50+ years ago, the crimp was because the tolerances were nowhere as good as today, and some were out of spec and looser, so the crimp is the easy fix all to not have precision dies and tooling like we have today?

I measured some ammo from 70's and it was junk specs compared to even Tula or whatever junk you can buy, was way better. Also, today, they make different sizes of primers. Some are 1/2k larger and are very tight in just about anything.

Just guessing.
 
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