decapping IMI(israeli) milsurp 5.56 brass

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Apr 18, 2015
San Marcos, TX
ok, so maybe I'm naive but
  • i got a "good deal" on 2K x 5.56 IMI brass with crimped primers
  • take 1: install lee universal decapping die, watch pin move right up the collet, primer she no move
  • torque that collet down h-a-r-d
  • take2: snap decap pin, primer she still no move

I've only decapped a few tens of thousands of pistol and rifle brass so I think I know the basic idea. Is there some very obvious stewpittity that I'm committing here. I just ordered 4 more decap pins, but unless I up my game that will soon be $15 down the drain
Instead of torquing it down hard, just gradually tighten a little at a time until it will stay in place and decap. Also use steady pressure on the downstroke of the press handle, not a fast sudden movement.
They could have slightly off center flash holes and the decapper pin is hitting more brass then primer I have seen this before
Take the stem out. Use a degreaser/brake clean to clean the stem and collet ID to get all the oil/grease off. Reassemble and tighten collet down, Hard...

Just to make sure and so you can look directly; cut one case in half to get a good view of the flash hole(s)...
I use the Lee decapper with base. It is around $10 and you will not break it. it is a little slower but works.
I use the Lee decapper with base. It is around $10 and you will not break it. it is a little slower but works.
I second this. I use a Lee decapper as well for milspec 5.56 brass and it works like a charm. IMI are indeed a standard flash hole, they are just seriously crimped from the factory. Way more tightly crimped and in a different fashion then say LC or WCC NATO brass. (At least the IMI M193 I have is like that, the IMI .223 55gr FMJ in .223 stamped brass is not crimped)
Anyway, you have to use a solid decapper and a firm consistent motion of actuating the press handle, and you can pop them out. It will only be an issue this one time, as afterward you will swage the primer pocket to remove the massive crimp and then you'll be good from there on out. Don't give up, it's good brass. I use all my same Lake City case developed loads in the IMI NATO brass (09-14). I've also had good experiences with TAA headetamped NATO brass but again, after the very first firing you have to pop the crimped primer and then swage out the pocket. Just part of the deal.
I got into some older IMI brass a few months back. The Lee decapper was pushing the cup out of the primer, leaving the rim in the hole. Had to toss most of the brass. Need a way to cut the crimp with the primer in the pocket.
The brass may even have undersized flash holes? Really crimped primers should not be that hard to remove, no hammer and punch needed if it is something is not right
Jo-Jo may have the answer. I had the same problem with some Tokarev brass. The flash holes were smaller than the decapper pin.
The universal decapping pin is indeed larger than the standard decapping pin. I would compare your standard decapping pin diameter to the one on your universal die. Then size/decap using the regular die with lube. I bet it works.

FWIW I found that the regular Lee 357 SIG decapping pin too small a diameter on some brands of brass as it is.
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That's a substantial looking brass hammer head! Nice workmanship!
I use about the same setup, but mind doesn't look that good.
Mine being a machine nut, a ground down craftsman punch and a 2 pound machine hammer! It's got a 100% track record!
+1 on previous..You will find the most problems with too small of primer flash hole, and primer hole off center. It usually has nothing to do with the crimp.
Some of this brass is just not up to snuff to be reloaded...Bill.
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