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Discussion Starter · #1 ·


Does anyone have any idea what is up with this case pocket? I'm speaking of the ring. I've read where people take berdan primed cases and drilled them out and insert a brass ring then shaved it down. The case has one primer hole though vs. two so I am thinking it is not milsurp brass. Ideas?
 

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Discussion Starter · #3 ·
Manufactured in s. Africa? Maybe that case took a critter down there.

Ok, so should I use a pick to get it out and then just re-prime like normal w/o another crimp?
 

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Although I can't really read the headstamp (see explanation below), there is no reason to believe that your case is anything other than boxer-primed military surplus brass. The US military ammunition (and a LOT of other Boxer-primed military brass from elsewhere, Canada, etc.) crimped their primers into the pockets for reliability purposes.

(Fun Fact: Crimped-in military primers pretty much doomed John Garand's first new rifle design for the US. His first rifle design was to be 'primer actuated' and it depended upon the primer sliding partway out of the case in order to unlock the rifle, and naturally, it required uncrimped primers.)

If it is indeed a crimp you are seeing there (my computer is having a hard time tonight 'grabbing' the picture so I can enlarge it), you need to punch the used primer out through the crimp. The primer will usually come out deformed and swaged smaller than the primer pocket. You will need to remove the crimp before you reprime the case.

Depriming crimped-in primers is usually pretty hard on decapping pins (I have broken more than my share of decapping pins doing this) and if you are going to decap a lot of crimped-in military brass, you might want to invest in either a purpose-built Lee decapping die, or one of the Lee military primer decapping sets (OR a crapload of spare decapping pins).

Once you have the primer out, you need to remove the crimp before you can reprime the case. You can buy handheld tools to do this, but my experience is they are usually pretty hard on the hands to use.

With a little practice, you can learn to satisfactorily remove the crimp and properly bevel the mouth of the primer pocket by running a sharp pocketknife around the edge of the primer pocket, removing a small shaving of brass in the process.

EDIT. My computer finally 'ground through' your picture. Despite the date, the case is Canadian-made postwar 8X57 (I have an unopened 1144 round case and several hundred more rounds of that stuff (unfired AND reloaded) sitting around).

I consider it about the best surplus 8mm I own (and I do have a LOT of it) and once you get the crimp out, the brass reloads GREAT.

Personally, I prefer that brass to just about any other Boxer-primed 8mm I have used for reloading. It lasts a LONG time.
 

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Discussion Starter · #5 ·
well all of these 8x57 casings are reloads from a few years ago that I bought at a show. this is the only case in the entire lot. I think i'll just toss it out and forget about it as it seems too much trouble. thanks for the info.

at any rate, I have all my brass cleaned and resized/deprimed, trimmed and chamfered. I may load a few .280 rounds tomorrow and throw a few down range.
 

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well all of these 8x57 casings are reloads from a few years ago that I bought at a show. this is the only case in the entire lot. I think i'll just toss it out and forget about it as it seems too much trouble. thanks for the info.

at any rate, I have all my brass cleaned and resized/deprimed, trimmed and chamfered. I may load a few .280 rounds tomorrow and throw a few down range.
If that case was reloaded, it is probable that the crimp was already removed by the guy who reloaded it previously. Before you pitch the case, try repriming it with a used primer. If it slides right in, you are good to go.
 

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Cases with "MM", 7,92 and two digit Date are NOT South African, but CANADIAN-made for CIA Covert ops in the 1950s. Very good Brass, Ring Crimp Military style. Either swage it out (RCBS, Dillon tools) or ream it out ( all makers).

Doc AV
 

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Discussion Starter · #10 · (Edited)


I put the caliper inside the primer pocket ring of that case and it comes out to approximately .207 depending on what position it is rotated in. I got just about exactly the same with other 8mm brass with r p or umc, etc., headstamps (all of which were reloads).

I checked in the gun cabinet drawer and found 4 more of the same case marked the same but 41, 42, etc.

The spent primers are gone so that idea is out.

So that ring needs to come out for sure?
 

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It doesn't really need to "come out", just moved and set back enough to insert the new primer. Don't try to remove too much brass or ream the hole too big.
 

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The "ring" is simply a staking mark who's sole purpose is to keep the primer from backing out under fire and locking up a weapon. It's merely a stamp that pushes a tiny amount of brass into the sides of the primer to wedge it in place. A swaging die will push this brass back into the sides of the primer pocket to return the pocket to it's original size making repriming easier. After I swage cases I tke my case mouth reamer and give the primer pocket mouth a quick ream (usually just one quick twist) to remove any sharp edges that swaging may leave.
 

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Greetings-
I have 40 of these I got from a show. I used a primer pocket reamer and took a little of the crimp off. Without exaggeration I have reloaded them over 15 times with no failure at all. Mine were not berdan primed but were marked 44.
I don't want to disagree with Doc AV but when I researched mine i found it was South African-
Musgrave Manufacturers and Distributors (Pty) Ltd, P O Box 183, Bloemfontein, Republic of South Africa

I found this information from this site. http://cartridgecollectors.org/?page=headstampcodes#M

Please correct me if this information is wrong.
 

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Discussion Starter · #14 ·
So the ring inside diameter needs to be wider? Up above they mentioned that it needs to be pushed back outward if I am not mistaken, which increases the diameter....of course without removing any of the inside diameter material.
 

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So the ring inside diameter needs to be wider? Up above they mentioned that it needs to be pushed back outward if I am not mistaken, which increases the diameter....of course without removing any of the inside diameter material.
The crimp only effects the bottom edge of the primer pocket. When you get past the crimp, the diameter of the pocket is precisely the same as on an uncrimped case.

Your goal in removing the crimp is to just get rid of (or displace with a swage) the metal that makes up the little ridge on the end of the primer pocket that will interfere with inserting a new primer, which is going to be of a larger diameter than the inside edge of the original crimp.

Ideally, after the crimp is removed, you will end up with a small bevel or a rounded corner on the end of the primer pocket that will help guide the new primer into the pocket. It should have a 'rounded' profile on the edge, just like what you see on commercial cases.

Sometimes the crimp is made so deep that you can't completely remove the 'ring' without removing a WHOLE LOT of material. Even if evidence of the 'crimp ring' remains, as long as the 'entry diameter' into the primer pocket is sufficient to accept a new primer (and the 'mouth' is properly shaped) the case should be good to go.
 
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