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View Full Version : Reloading steel case 7.62x39mm with standard primers.



Mauser 98K
05-02-2018, 08:03 PM
this is a little something i did just recently for a "what if" and "why the hell not" reasons. it is also nice to know that i can if i had to reload the steel berdan primed cases. this was done for some berdan brass cased .308 that i had laying around but figured id test it out on some steel cased 7.62x39mm.

the first thing to be done is to remove the old primer cup..
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the easiest way i know of to remove a berdan primer cup is by filling the case with water and using a rod that will just slip in and whacking the rod with a hammer. this pops the primer cup right out of the case with little to no effort and you can reuse the primer cups for a later project.

the second thing to do is to remove the dimple.
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you may or may not need to do this depending on if you just want to remove the anvil from a fresh primer and use the dimple instead.. i removed the dimple in my cases as it makes it easier to just use a standard decapper tool and also i would have to modify the pocket swage tool i made to clear the dimple. this might be a waste of time in reality as you can usually only get about 2 or 3 reloads out of the steel cases to begin with. probably would just be easier to just add in a small clearance hole in the swage tool to clear the dimple and then just remove the anvil out of the fresh primer and use the berdan anvil/dimple.

the 3rd thing if you removed the dimple is to drill the center flash hole in the primer pocket.
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the best way i have found to get the correct size of the hole is to find a boxer case and find a bit that will just fit the center hole in the boxer case. it may also be a good idea to made a drill guide to keep the bit centered in the primer pocket. the way i did it was to drill from the inside of the case as the dimple can aid in keeping the bit centered also.

the fourth thing that needs to be done b4 you can go any further is to make the pocket swaging tool itself..
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i made mine out of an old grade-8 bolt and heat treated it. the swage tool slides into the primer pocket and a small ring will press metal around the swage tool till it measures .210 and this will allow use of standard primers..

the fifth thing to do is to swage to primer pocket smaller..
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measurement of pocket b4 swaging..
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and measurement of pocket after swaging.
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if all went well then you can now just seat a regular primer in the case.
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and then you can put in the powder and the bullet and you then have a finished round that can send lead down range.
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and that is pretty much all there is to reloading the steel case or other berdan 7.62x39mm.

do keep in mind that some cases will have a lot larger primer pockets. this method works ok for the .215 primer pockets but will not work for the very large pockets..

Mauser 98K
05-02-2018, 09:21 PM
i been thinking and done got me an idea now about how to speed this up greatly.. instead of drilling the dimple out, and as it was once part of the bottom b4 they swaged the dimple in the primer pocket, set up a punch and arbor that basically just punches the center hole and flattens the dimple at the same time and make the flash hole like the factory guys do it. this way all i would have to do is deprime, punch the center hole out which also flattens it, then swage the hole and prime. ill have to look into this idea tomorrow. if it did work then it would make converting berdan to boxer fast and easy with no drills or power equipment, just use a reloading press.. gonna have to study on this one.

salty dog
05-03-2018, 07:53 AM
I'm confused on how you swage down the case to make the primer pocket smaller. I read your mention of a "ring" but it seems like whatever you use it would take a lot of force.

It's academic for me, I'm just curious.

Mauser 98K
05-03-2018, 08:42 PM
well the mandrel is the size that a normal primer pocket is. this mandrel goes into the primer pocket. there is a small ring above the mandrel that squeezes the steel of the case between it and the anvil that goes into the mouth of the case. the metal that is being squished has nowhere to go but inward into the primer pocket and gets squeezed around the mandrel thus swaging the primer pocket smaller...

and yes it takes some force. im using an arbor press.

salty dog
05-04-2018, 12:44 PM
Makes sense. Thanks for the answer.

Mauser 98K
05-18-2018, 01:53 AM
sat down and did all the measuring of the cases, bullets, and loaded rounds. got the internal volume in cm3 of liquid, seating depth, and the whole shebang, and run the numbers through Quickload and my ballistics calculator.. this is about as close as i can get without actually having the chronograph and the means to measure bore pressures..

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and plugged into my ballistics calculator so i have a little idea of what the heck is happening.
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all gotta do now is align my scope and zero the bugger in to see how they print.

Rcmaveric
05-18-2018, 02:58 AM
I have thought of it. My problem is i am converting it to Grendel brass. People need to stop being cheap and shoot some brass for me to pick up. Either there are no people shooting brass 7.62x39 or the other range scroungers are cleaning it before i get out there on the weekends.

Mauser 98K
05-18-2018, 03:43 AM
im not sure many actually shoot brass cases myself. i have seen buckets come in through the recycling center that had a lot of 7.62x39 cases but out of those buckets i have only seen like 6 brass cases out of hundreds of steel cases.. but it could be like you said, someone else could be beating you to it.