Anybody make primer cup dies?

[Desertbuck]

Well here I am again. After the success of all who shared their information on the
(Can you make priming compound?)
thread that I started seemed not long ago. I have gotten comfortable making my own compound. Contemplating on having a set of dies made to make primer cups... I think dies designed to make gas checks seem like the logical place to start. What do you guys think? The Anvils are definitely the tricky part. But I think I have plenty saved up from used primers for the time being. Having fresh primer cups to work with sure seems like a good idea to start.

[TyGuy]

I think this is a good goal. What little primer reloading experience I have has shown me that the cups are the “wear item” of the primer. It doesn’t seem like the anvils suffer much damage from use but the cups do wear thin and flatten. A set of dies to punch out fresh cups sounds like a smart tool to add to the repriming toolbox. Looking forward to seeing where this goes

[Scrounge]

Not yet, but planning on it. Got more shop setup to do. Traded my 7x mini-lathe for a Unimat SL, which would be a micro-lathe, since I could pick the whole thing up with one hand. Still have the Atlas TH42, 10x24, and maybe the Smithy CB-1220XL. It's apart, getting the spindle cleaned and degreased & regreased. Any of you have any idea what the primer cups should be made out of?

Bill

[Desertbuck]

Not yet, but planning on it. Got more shop setup to do. Traded my 7x mini-lathe for a Unimat SL, which would be a micro-lathe, since I could pick the whole thing up with one hand. Still have the Atlas TH42, 10x24, and maybe the Smithy CB-1220XL. It's apart, getting the spindle cleaned and degreased & regreased. Any of you have any idea what the primer cups should be made out of?

Bill
I was thinking 28 gauge or 27 gauge brass or aluminum. According to my calipers that's the general thickness of primer cups. Only reason I might choose 27 gauge is possibly for the stretching from forming the cup.
The average measurement I see with an analog set of calipers is .0150in to .0155in

[Scrounge]

I was thinking 28 gauge or 27 gauge brass or aluminum. According to my calipers that's the general thickness of primer cups. Only reason I might choose 27 gauge is possibly for the stretching from forming the cup.
The average measurement I see with an analog set of calipers is .0150in to .0155in

From what I've been able to find, which isn't very much, it seems like they're more likely to put a small metal slug in the cavity of a die, shove a stepped punch into it to form the slug into a cup, and then push it out with a flat punch from the other side. Though I could easily be making it too complicated. ;) I was looking at copper, but that was mostly because it's fairly easy to work cold. That and some primer cups are still made of copper, if I understood what I was reading, and if it was a reliable source. Since I can't remember where I read it, I don't think it would be good to bet on it. I have downloaded some old books on making ammunition from Archive.org, but haven't gotten to read any of that material, yet. Couldn't possibly have anything to do with ADD.

Bill

[rancher1913]

noe makes a resizing die that works on small primers, the guys modify the ram because its to big but the die body works. I believe noe is working on a set up just for the primer guys, but it is not available yet.

[Cap'n Morgan]

According to G. Frost's book "Ammunition Making" primers are punched from strips. The thickness is .0265" for large rifle, .0175 for small pistol.
The primer is punched and cupped in one draw, then sized in a second die.

https://i.imgur.com/n79rmv4.jpg

https://i.imgur.com/kbyuuGw.jpg

[BunkTheory]

actually in theory you COULD simply keep flattening used ones out, although i think the primers i have popped out of fired cases always seem to split into pieces when i do get them out.

[TyGuy]

actually in theory you COULD simply keep flattening used ones out, although i think the primers i have popped out of fired cases always seem to split into pieces when i do get them out.

You can for a while, but the metal gets stretched upon being struck. This will eventually get too thin. They also tend to go flat, like a sign of over pressure. If one could simply replace their worn out cups with new ones and keep using the anvils, all the better.

[rancher1913]

most are only reusing the cups once or twice. somebody did a test and got 10 out of a cup before it was destroyed.

[dverna]

There are "one step" GC makers and that is where I would focus if I ever wanted to do this. Re-making primers is labor intensive enough without adding more steps to the process.

I think you are on the right path.

BTW, the work that Casting Fool (IIRC) is doing shows a lot of promise wrt having a practical process to re-manufacture primers. He has done the best job of laying it out and reporting results.

[n.h.schmidt]

Maybe Copper 224 gas checks could be resized to .210 For the large type primers. Resize them to .217 for berdans too. Also copper 25 cal gas checks could be sized to .250 for berdan primers.They could work for many 303 cases and 7.62x 54r cases. If they are not tough enough for full power ,I bet they would work for light loads.

[deltaenterprizes]

According to G. Frost's book "Ammunition Making" primers are punched from strips. The thickness is .0265" for large rifle, .0175 for small pistol.
The primer is punched and cupped in one draw, then sized in a second die.

https://i.imgur.com/n79rmv4.jpg

https://i.imgur.com/kbyuuGw.jpg

You beat me to the reference to Ammunition Making by Frost!

[Scrounge]

Regardless of who posted it first, it's really good info! Veilen Danke! And that is one of the books I've downloaded. May have bought a dead-tree copy, too. I've a number of books here I've not had time to read yet. I collect books with the intention of reading them later, when I'm desperate for something to read. Mostly right now I'm working on the shop, or stuff to go in the shop. I gave up my mini-lathe last week. Traded it for an Unimat SL 1000, which is more of a micro-lathe, and some cash. Which is mostly spent getting more stuff to pile in the shop with the Unimat. I'm thinking it might be a bit small to be making dies even from primers, but it should be ok for punches. ;)

Bill

[beechbum444]

following this thread..........kinda got me wondering, what would blank ( non active ) primers for for per 100????? and how big would the market be??? Even if one had to design a machine to makes these by the thousand, how much could such a machine cost??? Maybe a few grand ???

[trapper9260]

I was thinking also make them like you would a gas check also.

[kywoodwrkr]

Useful life of cases is extended by annealing.
Would this be a viable option with the primer cups?
Thanks

[TyGuy]

Useful life of cases is extended by annealing.
Would this be a viable option with the primer cups?
Thanks

The issue does not seem to be work hardening but material displacement. One of my theories is that the brass of the cup is stretched when struck by the firing pin. When you hammer the dimple out that material has to go somewhere and it seems to like to migrate out to the edges. Either that or the primer just gets flattened by the repeated firing. I’m still taking baby steps in this process so take that opinion with a block of salt.

[slim1836]

Useful life of cases is extended by annealing.
Would this be a viable option with the primer cups?
Thanks

My opinion only is that it would be possible if you can control the hardness of cup/anvil to spec. +/- of factory specifications, of which I know nothing about. Any hardness outside of factory specs. and you may be flirting with disaster.

That said, I have delved into the roll cap method on rebuilding boxer and berdan primers but have not shot them yet, more out of curiosity.

Slim