What Is A "Crimped Primer"?

[UtopiaTexasG19]

I was looking at some of the "once fired brass" vendors on the Internet and some are selling .223 brass with "crimped primers". Does this mean the fired primers are still in the casing and need to be removed or is their another meaning to the "crimped primer" notifications? Thanks...

[Tatume]

Primers are crimped into military ammunition to enhance reliability. There are several methods of crimping, including a multiple stab crimp, or a circumferential crimp. Either way, it is necessary to remove the crimp prior to reloading the case. Seating primers into such cases without removing the crimp can cause detonation. Several companies make dies or reamers to accomplish this, including RCBS (which I have and find unpleasant to use). Although I've not tried one, the Dillon is reputed to be the best, although it is expensive.

[carlsonwayne]

As far as I understand it, they are crimped in. Most military brass has crimped primers. They are a little harder to remove, but not a whole lot harder. The hard part is seating a new primer. Most of the time you can just force it in with little effort, but sometimes they won't go in. I use my chamfer (I'm not sure how to spell that, or if it is even the right name) tool to ream it a little. You'll find 9mm brass with crimp as well. I think Dillon makes a tool that removes the crimp, but my way has worked for me for 20 years, and the guy who taught me how to do it has been doing it longer. After the first new primer, they reload the same as any uncrimped brass. If you do it my way, use steady even pressure to seat the primer. If you do it fast there is the potential for detonation, as Tatume said. I have yet to have a detonation, and I hope I never do. Just like removing live primers, slow even pressure reduces the potential for detonation.

[geargnasher]

I've never had any luck seating a new primer in a crimped case without reaming or swaging the pocket. Just deburing it won't help much. I have the RCBS swager, and it isn't worth the box it comes in. It needs a short (pistol) AND a long (rifle) swager for the rifle brass, the "large" swager only does about 2/3 of the pocket and leaves a ledge that makes the full seating of the new primer a bit dicey. My solution was to have a machinist turn a new swager and harden it for rifle brass.

Gear

[UtopiaTexasG19]

Thanks for the replies. I can find brass once fired without the crimp for almost the same price so at this point see no reason to add extra work to my reloads.

[JIMinPHX]

The picture below shows:
Left - crimped
Center - never been crimped
Right - Crimp was removed by a chamfering tool

The crimp shown is a fairly common style that is sometimes called a ring crimp. Three point staked crimps are also common on some military brass. There are other types of crimps as well, but I don't see them very often.

If you get brass with the crimp still in it, there is extra work involved in removing the crimp, but there is also the added advantage of being fairly certain that the brass really is only once fired.

There are people out there that will remove the crimp from large quantities of brass for fairly reasonable money. Just off the top of my head, I think that the going rate is around $.02 per case, but don't quote me on that. I just de-crimp my cases with a cordless drill & a chatter-less chamfering (counter sink) tool.

[Lizard333]

Buy the Dillon swage. It worth every penny. Its what I use.

[Tatume]

I have yet to have a detonation, and I hope I never do. Just like removing live primers, slow even pressure reduces the potential for detonation.

I was in the room when my friend had a primer detonation. It was surprisingly loud; it seemed as loud as firing a revolver in the room. My ears were ringing afterwards.

It was very forceful. The detonation could easily cause injury, including loss of an eye.

It's not worth the risk.

Take care, Tom

[casterofboolits]

I have used thr RCBS primer pocket swager for over 25 years, but with hardened tool steel (A2) mandrels I made for it. Works great for me. One advantage of being trained as a machinist.

[Walter Laich]

remember you only have to remove the crimp once, not each time

I have the Dillon (E-bay find) and really like it. You do have to do a bunch to make it cost effective, though.

walt

[goofyoldfart]

once when using the "old" Lee "whacem" loading dies, I had a detonation of a live primer that had somehow gotten into a pile of fired brass. Good thing that I was using a large deadblow mallet-- the face of the mallet deflected the discharge from the primer. Mother was not happy, though, the kitchen table had a hole the size of the primer burned through it completely that looked like it was burned with a laser. totally smooth. It was a Formica table top. on top of all this, I had to go into the attic to get the decapping rod that was blown through the ceiling. It sure did wake me up to use more caution. God Bless to all.

Goofyoldfart.

[JIMinPHX]

I had a few primers go off when loading .30-30s in a Lee Loader, back before I learned that if you are going to double tap a primer into place, you don't want to let the priming rod bounce up before taking the second swing at it. My experiences weren't nearly that exciting. I just got a little pop & some smoke. The priming rod never shot out of the case.

[midnight]

I find the Wilson reamer does the best job of removing the crimp. I started with the 50BMG. There is a lot of crimp to remove there. The Wilson shellholders hold the case in alignment and the cutter only has flutes on the sides so it will not deepen the pocket. The whole deal is expensive but I havn't had a SWMBO for a long time now so that solves that problem.

Bob

[JeffinNZ]

I have used the RCBS pocket swager on some 1943 vintage .303
Brit brass and it worked great.

I always thought a crimped primer was one that couldn't reproduce......

[michiganvet]

Crimped primers were origionally intended for use in fully automatic military arms. A lot of LC brass was produced without crimping. The Lyman chamfering tool works as does the RCBS primer pocket swager but uncrimped brass is lots easier. I often collect range brass and although I have both tools the crimped brass is "leverite" where I find it.

[Hang Fire]

Keep an eye peeled for military national match brass. No primer crimp and very good uniform brass.

Years ago I got a five gallon bucket full of once fired 7.62x51 NM brass for 20 bucks, one of the better deals I ever made.