Removing crimp from primer pockets?

1sailor

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I bought a new M&P15 a couple of days ago and my son and I took it out in the woods today to shoot. We blew through 160 rounds pretty quickly (what a fun gun to shoot). I have been reloading 9mm for a couple of years now but am not too familiar with crimped rifle cases. Is it a hassle removing the crimp from military brass or pretty painless. Most of the used brass I find for sale is either military or mixed range brass.
 
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It's kind of a pain, but you only have to do.it once. There are tools.available that will make short work of a bunch of cases.
 
Yeah, that's kind of what I thought. I have to buy some other stuff anyway if I'm going to reload .223 so I'll just add one more tool to the list. Any preferances.
 
What's the preferred method for removing the crimp from the primer pocket. I was going to buy a forester trimmer but that's not going to clean up the primer pockets unless there's an attachment.
 
RCBS has a $35 tool to swadge the brass back into the pocket where it belongs. It works very well and there's no change of removing too much material.
RCBS Primer Pocket Swager Combo 2

RCBS and Dillon have bench swagers that are very fast and efficient but cost more.
The RCBS is $80 RCBS Bench Mounted Primer Pocket Swager and the Dillon is just over $100. https://www.dillonprecision.com/#/content/p/9/pid/25263/catid/8/Super_Swage_600

You can buy very inexpensive hand held or drill bound trimming tools for almost every company and there are also very expensive tool ends for the drill too.
Lyman Case Prep Multi Tool
Lyman Primer Pocket Reamer Tool Small
Lyman Primer Pocket Reamer Tool Large

I own a Forster Case Trimming tool and it's actually a small lathe. They also sell the bits for removing the crimp with the Forster Trimmer.
Forster Original Classic Power Case Trimmer Primer Pocket Chamferring

All of them work, it comes down to how much do you want to spend and how much time do you want to spend doing the work. I use the RCBS swaging tool on a single stage press and that works just fine for me but now I'm thinking of buying the bits for the Forster trimmer if that will save me some time.
 
If you decide to go the swage route, no matter what brand you use, you really need to sort your brass by headstamp and if known, year. The web thickness varies and you need to adjust the swage for the thickness you are swaging.

I have the original RCBS swage tool. It has worked well for me after some minor changes. I use mine in an RCBS RockChucker. Even when sorting brass, you will encounter one from time to time with a thicker web. Having some feel on the press handle will prevent damage to the rod. I have swaged over 20K on mine, and knock on wood, have never bent the rod. But normally folks will bend the rod when first learning how to use. RCBS now offers a generation 2 that is more resistant to bending.

I bought the Dillon swage after hearing everyone rave about them. I used it just a bit and found it didn't offer me any advantages over my RCBS tool, so I ended up selling it.

I personally prefer swaging since it actually forms the primer pocket into a nice uniform size. It doesn't remove metal from the bottom so if they aren't deep enough, that is still going to be the same. I like the like radius it leaves on the leading edge to the pocket. If there is a burr where the flash hole was punched, it will tend to close off part of the flash hole. So uniforming the flash hole is suggested. I do that anyway on all my brass during my initial prep step, so it is not big deal for me.
 
One other point needs to be made here. In addition to the primer pockets, you absolutely need to trim your brass to length, and case length should be checked after each sizing, but before loading. 223 brass stretches pretty quickly in most ARs. Don't bother measuring case length until after you have sized it, measurements taken from a fires case are inconsequential. I always size cases on my single-stage, then tumble them and trim. I use a Gracey trimmer, which is a high speed design that trims and chamfers cases at the same time (expensive), but you can get the same end results with the Forster trimmer you mentioned earlier.
 
I've always used a Lyman pocket reamer and chamfering tool to remove crimps on 5.56 mil brass and never had a problem. Crimped 9mm brass is another story altogether. I'm putting a pocket swager on my Xmas wish list.
 
On the few military cases I've used, I used my RCBS case mouth chamfering and deburring tool. I wouldn't want to do hundreds of cases with it but it worked well for me.

Ed
 
You can get into as much $$$ as you want to obtain a crimp removal tool, but, as a life long machinist/mechanic, working with metal for mebbe 50+ years, I use a countersink. Fast, easy, safe, and a lot less expensive than some of the tools offered for the job. I take a counter sink (I have a half dozen in my toolbox) and a twist or two will cut the offending metal out of the primer pocket. If I have a lot of brass to work on I can chuck the counter sink in a drill. McMaster-Carr
 
The best method I found was to first sharpen the small blade of my pen-knife and use the tip to remove the majority of the crimp. Do it a few times and you get a feel for how much to trim away. Then use a Lyman primer pocket reamer and finally the primer pocket uniformer ( both little hand tools) to finish the job. I got more time than money and the hand tools were much cheaper than some fancy machine I would never use again.

Gary
 
+1 on the swager, because it removes no metal. My RCBS unit has done many, both large and small, without problems. A further +1 on sorting cases at least by headstamp, as the pockets or crimps may differ slightly.
Cases will eject from the swaging punch more easily if just the teensiest film of resizing lube is applied to the punch every 10-20 pieces.
Larry
 
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I've used one of these for years on the primer pockets of both .223 and .308 brass. This chamfer tool came with my RCBS reloading kit, so it was already available.

I usually work in batches of 100 or so. All it takes is a quick twist to remove any excess crimp metal remaining after de-priming.

I believe in keeping it simple.......if I were to load thousands of rounds in a sitting, I might consider buying a dedicated tool, but have never seen the need.

Lou

RCBSchamfertool_zps147099a2.jpg
 
Well it would appear that decrimping is more of an art than a science. What works well for one guy doesn't necessarily work for the next. I do appreciate all the advice. I think I'll start with some of the least expensive methods and if I have trouble I'll move up the ladder. If all else fails I'll spend a couple extra bucks and buy some non-crimped commercial brass. i do find it interesting that often new brass is as much or even more than loaded ammo. Once fired is cheap enough though.
 
If money is no object then the Dillon swage is No.1 and a good investment, if you are going to do a lot of brass. Any time you hold the case in your hands and do your crimp removal you will get sore hands an fingers. I did three five gallon buckets of .223/5.56 brass and my fingers got very sore and in the end I wished I would have bought the Dillon unit.

If you want to save money I would buy the primer pocket reamer for the RCBS prep station. It will only remove the crimp and bevel the mouth of the primer pocket. I have the RCBS press mounted swager, the Hornady reamer, and the CH4D unit and what is pictured below works the best out of what I have above.



When the rear of the case touches the face of the reamer your done and the primer pocket looks like it was done at the factory.



Below, two of the three buckets of brass and why I had sore fingers. :(
 
I've used one of these for years on the primer pockets of both .223 and .308 brass. This chamfer tool came with my RCBS reloading kit, so it was already available.

I usually work in batches of 100 or so. All it takes is a quick twist to remove any excess crimp metal remaining after de-priming.

I believe in keeping it simple.......if I were to load thousands of rounds in a sitting, I might consider buying a dedicated tool, but have never seen the need.

Lou

RCBSchamfertool_zps147099a2.jpg
There's what I use with great satisfaction. Stick it in and give it a twist. The good thing is that since you reload, there's likely one already on your bench.
 
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