How to decap spent primers w/o full length resizing

G

Gunzer

Inactive
New AR308 build. This rifle will always host my Omega suppressor. I put 60 rounds of Federal match ammo through it. My newly fire formed cases reveal slight over pressure. The spent primers are flowing around the firing pin such that the spent primer 'crater' exceeds the case head by about .001"

My cases won't flush up against my micrometer for an accurate reading when using my head space comparator.

I intend to measure these cases so I can bump the shoulder .002" with my die, based on my rifle's chamber dimensions. I don't want to resize these cases in the process of removing these cratered primers. How can I decap these cases without full length resizing them in the process?:confused:
 
Get a Frankford Arsenal hand depriming tool. Maybe 30 bucks and can be used on almost any centerfire cartridge.

you may have a problem with an oversized firing pin hole.

Cratering without other indicators usually doesn't mean much.
 
If you have a RCBS FL die, just turn the screw down so that the decaping pin protrudes far enough to push the primer out without sizing the case at all. I have done this hundreds of times. And broken a decaping pin only once.

Once the decaping pin and expander ball are adjusted far enough. Tighten the jam nut, otherwise the pin may wobble and break.
 
The easiest way is what "kilotanker" said. Just make sure you don't extend the decapping rod too far, hit the web of the cartridge, and bend the rod.

Another way is simply to buy a decapping die. Lee, RCBS, Hornady, Lyman, and Redding all make them. The cost runs from 12 $ for the Lee to about 60$ for a set of Redding decapping dies. The others are somewhere in between.

You can also buy a Lee decapping rod and base for about 8 $. You essentially set the cartridge in the base, insert the rod, and then hit the rod with a hammer. It's effective but slow. However, I've found that it is the only thing that works on military cases with crimped in primers.
 
I always decap everything with a Lee decapping die before cleaning. Many many thousands of rounds and only replaced the rod once due to missing a Berdan primed 7.62x39 case I picked up at the range.
 
Every reloader should have a Universal Decapping Die. They are so useful. I have had my Lyman now for about 30 years.

Don
 
In support of those who recommend a universal decapping die : It won't have any effect on your fireformed brass. It only decaps.

Its highly recommended you run your brass through whatever cleaning process you use before you run your brass through your dies.Dirty brass will erode your dies.

If you decap before cleaning,your primer pockets will be cleaned (by most processes)
Adjusting the sequence of your process to first decap,then clean,will make your problem moot. You will have clean,decapped brass before you set up your sizing die.

So,yes,you are on the right track to decap first. The Lee universal decap die is a good,economical tool.

I appreciate and understand your target of .002 head clearance. That is the ideal for bolt guns.

For reliable full lockup on self loaders reliable sources (such as Precision Shooting's Handloading Guide for Competition) suggest a little more head clearance. I'm not the expert to tell you how much. I might suggest .004 for an AR-10. You will have some variability in the brass after sizing. Lets say you don;t want your worst case brass to have less than .002 head clearance.

If over time, if your measurements show .002 variability,it might be best to compensate with a target of .004.

But you are taking a very good approach. Well done!
 
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Universal Decapping Die, definitely the way to go - I've got three since reviews led me to try the Lee after already having the small RCBS, and large Redding versions.
 
I have used the Lee universal decapping die, in a Lee hand press for years. Recently I bought 3000+ range brass and wanted something faster. I bought one of these:
Get a Frankford Arsenal hand depriming tool.
Click to expand...
It is easy to use and faster, and can be done while watching TV.
Either one deprimes without touching the brass with any metal. The deprive rod only touches the primer. The Frankfort comes with three different sizes of plastic collets to hold the brass. $39.99 @ Brownells.
I firmly believe it is best to decap dirty brass first (you can wear latex or nitrile gloves), then wet tumble with pins to clean and scour primer pockets. When you see how much dark black filth, including lead primer residue, comes out in the solution, you will never want to handle dirty brass again. The solution includes citric acid and renders the residue safe for toilets and sewage plants. I would not put in in a residential septic system. The deprimed brass drains faster, too. I would say the separating he steel pins is more work than drying the clean brass. Use distilled or Reverse Osmosis water to clean/rinse faster and leave no hard water residue.
 
I use the LEE "military decapper" punch and base set. No idea the cost today, but its cheaper than a die, doesn't take up a spot in your press, is virtually indestructible, and, you get to hit something!!! :D

OK, its slow, its 100% manual, but you get to feel the pin go into the flash hole, and so it will do cases with off center flash holes too. IF, SOMEHOW, you manage to break it, Lee will send you another.

Get the set that has two punches, one for .22 cal and one for .30 cal. They'll work for every centerfire that isn't Berdan primed and shorter than the .50 BMG

:D

An added plus, if you have bent case mouths in .22 or .30 the punch can do a fair job "rounding" them back out so they can go in the sizer die.
 
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