6 Attachment(s)
Making Sparkplugs: My first 100 primers
Hello all and I hope your Thanksgiving was a good one.
Like some of you, I was pinched by the primer shortage. I have plenty small rifle and large rifle primers from my last big order years ago, but I simply shot up all my small pistol primers(I have no need of large pistol). While deployed overseas last year I started researching the feasibility of remaking used primers. I quickly stumbled upon Aardvark Reloading and looked through the extensive pdf available there. I got started partly because I need primers, partly because I wanted to see if I could do it, and partly to validate the process in case it becomes necessary in the future.
Disclaimer: I will not sell them or take part in any other illegal activity, and I'm not interested in discussing illegal activity. I made these for use in practice ammunition only.
In short, the pdf describes a brief history of primers and discusses a variety of different formulations. It turns out that primer compositions are a bit tricky. What follows is some information you already know, but probably haven't thought much about. They must be sensitive enough to ignite with the strike of a firing pin, but not sensitive enough to ignite when dropped. They must be extremely reliable. Beyond those obvious requirements, a few more characteristics come into view. It would be nice if they did not chemically destroy the brass casings when fired. Also, many older compositions were very corrosive on barrels. The H-48 "Prime-All" formula is of this type, requiring barrels to be cleaned immediately after firing. Newer lead-free requirements place additional restraints on primer compositions. Also, it would be great if purchasing the necessary chemicals didn't immediately put you on a federal watch list. The pdf gives quite a few different primer formulations, I haven't counted how many, perhaps 15-20 or so, and they are broken down in categories by type such as corrosive, non-corrosive, field-expedient(based on using toy caps or match heads) and even some lead-free formulations.
To get to the point, I selected the EPH-20 recipe. It is a non-corrosive recipe that purportedly offers high reliability, relatively low cost, is non-corrosive, and seemed to be less technically challenging to make, in addition to being one of the safer methods since the formula does not become explosive until after it is packed into the primer cup, wetted and allowed to dry.
Here is the CLIFnotes version:
Materials:
Sodium hypophosphite (ebay, $14)
Lead Nitrate (Amazon, $18)
rubbing alcohol
distilled water
glass beaker set ($20 ebay)
Hotplate stirrer ($35 ebay) Not absolutely necessary, but makes the synthesis a little easier.
glass stir rods and eye dropper ($10 ebay)
ceramic mortar and pestle
syringe with hypodermic needle. I happened to have a few from years ago when my wife needed blood thinner shots. I'm not sure where you'd get this, but it made wetting the mixture in the primer cups really easy.
Leather punch (Amazon $15)
forceps for removing primer anvils
Steel punch that I made on my mini lathe for removing the primer dimple.
I also bought a 3mm aluminum plate that I drilled with 100 holes and a #16 drill so the primers would have a place to sit while I loaded them. 3mm because the height of a SPP with the anvil installed is 3mm. A Flat punch will seat the anvil correctly when the cup is at the bottom.
I won't go through the whole procedure, since you can just hop over to Aardvark Reloading and download the pdf yourself, but basically you have to synthesize Lead hypophosphite using the Lead Nitrate and Sodium hypophosphite using the beaker set and the hotplate stirrer. This part freaked me out a little, but I followed the directions and it seemed to work just fine. It took maybe an hour or so. I now had a small glass baby food jar half full of lead hypophosphite. I think I could make a couple thousand primers with this little batch, maybe 5k. If I ever ran out, I'd scale up the batch size and make enough for 50k primers and be done with it. I bought 100g of sodium hypophosphite and 500g of lead nitrate. This is enough to make I think 30,000 primers or so.
So a few days ago, I whipped up my first batch of 100 primers. I set them out to dry, and yesterday, I loaded 5 primers into casings for a test fire with no powder. To my complete surprise and delight, all 5 went bang, though one of them was not as loud. perhaps I didn't fill that one as full with the composition. After that, I loaded 95 rounds of 9mm with 3.0gr Bullseye and some 130gr PC'ed boolits. I'm taking them to the range today for a test shoot.
FAQ:
So how hard is it really to make primers?
It's a bit of work. Like reloading, getting set up takes time. The hardest parts were getting the anvils out, and grinding the pyrex glass powder with the nitrocellulose(Bullseye) The nature of nitrocellulose is that it is sticky and plasticky, and doesn't like to grind, so it took a while to get it to a fine powder. If you wanted to industrialize this, I sure a dedicated coffee grinder would speed this up. The best way to speed up removing the primer anvils is to throw a bunch of primers in a tumbler and let it run for a few hours. CCI SP's will reliably shed most of their anvils this way. If you use a lot of CCI, this will save a ton of time. Not many of the other brands shed primers as easily forcing you to pick each one out. In retrospect, the chemistry part to synthesize the lead hypophosphite was not too hard. I spent dozens of hours getting to the point where I could make the first hundred primers. Now, I can make 100 primers in about an hour plus the drying time. Most of the hour is flattening the primer dimples and grinding the glass/NC mix.
What seems to be the most dangerous part?
The lead hazards. I know we're all somewhat familiar with lead hazards, but here, we're dealing with powdered Lead Nitrate, which is very toxic and lead hypophosphite which is only slightly less toxic. There are beakers, stir rods, forceps, mortar and pestle, storage containers, and the actual primers themselves. Cleanup needs to be constant, and I'm still on the fence about how well I did it. The primer composition kinda gets everywhere. Not to mention the spent primers that need to be cleaned.
Attachment 292250
