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Discussion Starter · #62 ·
@wvhunter308,

In response to "what will they think of next?" I have spent many hours reviewing patents from all over the world looking for ideas and things to try. I recently reviewed patent US4336084 which concerned a safer method for mixing primer compounds. While interesting, the nugget I extracted from the patent was a rimfire primer formula that Winchester was probably using in the early 1980s. It was based on lead styphnate, which was no surprise, but what really got my attention was that the formula did not contain tetracene. Getting tetracene requires either a multi-step synthesis or access to an expensive, controlled precursor (aminoguanidine). So, a primer formula that does not need tetracene is quite appealing. I converted the patent formula to a safe Eley Prime type compound that I call EPS27:

EPS27, EP version of example 3 in patent US4336084
Ingredient % gr
Styphnic acid 23.5 7.8
Lead oxide 21.6 7.1
Barium Nitrate 26.5 8.7
Lead Dioxide 6.8 2.2
Glass powder 21.5 7.1
Binder 0.1 0.033
------ ------
100.0 33.0

I mixed up a batch of this compound and reprimed 10 resized and prepped 22LR cases. After allowing the primer compound to completely dry, several of the empty cases where fired in a Ruger SR22 pistol to evaluate their sensitivity and power. I am pleased to report that the compound fired with a bright muzzle flash and nice strong pop. The remaining cases have been reloaded with 1.0 gr Red Dot and a 20 gr lead projectile. These rounds will be tested during my next trip to the range.

In summary, the above rimfire compound works well and eliminates one of the more difficult to obtain ingredients normally needed for lead styphnate based primer compounds. I personally do not consider styphnic acid all that difficult to synthesize, so this approach to a non-corrosive primer compound may interest the more adventurous among us.

Marshall
 

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Discussion Starter · #64 ·
@Goldtrigger,

its good to know this can be done in a pinch, the chemistry has me a bit put off but its probably like making a pot of jambalaya once you know how to do it its no problem
The chemistry required to make styphnic acid is only slightly more involved than making jambalaya. The worse part is working with hot (100C) concentrated acid solutions. So, you run the risk of both thermal and chemical burns. However, with the proper equipment and training, anyone who is handy in the kitchen could make this stuff. I run this reaction on the picnic table behind my house. The only serious mistake I have made so far, is during workup of the final reaction mixture I got a few drops of the highly staining yellow solution on the wife's kitchen counter (while she was not at home, thank goodness). Thankfully, I found out that baking soda dissolves and remove these stains, that is the only reason I am alive today. If you saw the reaction done once, you would see how easy it is and be able to do it yourself. Plus a small run goes a long way. A 0.2 mole synthesis makes enough styphnic acid to reload 4,000-5,000 SP primers or reprime the same number of 22LR cases.

Marshall
 

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Discussion Starter · #65 ·
@All,

During a visit to the range last week, I tested some of the 22LR reloads I have made using 1.5gr Bullseye. Things where going great until 1 round decided to lose its rim during firing. The rim separated so perfectly that when I finally removed the remaining brass tube from the chamber you had to look very closely to tell which end was the case mouth and which end was the base. No harm done to me or the Ruger SR22 pistol I was using at the time. I guess this goes to prove that brass failure is one of the pitfalls of reloading. I am not discouraged by this unfortunate hiccup, but I do plan to be more discerning in my brass inspection. The metallurgy of any fired case is unavoidably different than when it was first made due to the stresses and temperatures of firing. Experience helps us decide when it becomes different enough that it can no longer be safely reused. There is a huge amount of experience on this and other forums to help us safely make these decisions on most centerfire pistol and rifle brass. Rimfire brass not so much. However, if you just happen to know anything useful on how 22LR rimfire brass should be inspected, I am all ears.

Be aware, I am only reloading 22LR for the challenge and learning experience. With prices having dropped to ~$20/500 round brick over the last couple of years, I have stocked up on new ammo in preparation for the next 22LR shortage. I was never "one of those guys" who staked out Wal-Mart waiting for shipments came in. Rather, I would pick up a brick or 2 each month after the last crisis had passed and shelves were well stocked. After a couple of years, my stocks are well into the comfort range. Being stored in sealed ammo cans in the cool, this ammo should last a very long time. Once I have completed my 22LR reloading experiments, I will write everything up for posterity and only use the commercial ammo I have purchased in the future.

Marshall
 

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Discussion Starter · #67 ·
@Pig Ninja,

Case cleaning and prep is the most time consuming operation. I typically clean the brass 3 times: 1. initial cleaning in ultrasonic bath, 2. wet tumble clean with SS pins, and 3. wet tumble clean/polish after resizing the cases. This takes at least 3 days if you allow the brass to dry between cleanings. Recharging the cases with new primer compound takes about a day and finally a couple of hours to charge the cases and seat the bullets. So, figure on about 4 1/2 days to process a batch of 100 rounds. If you keep reprimed cases on hand, the process is much quicker. Its time consuming, but I got plenty to spare right now.

Marshall
 

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Thanks for the report and the detailed information!

I'll stick to reloading centerfire cartridges, and buying rimfire ammo at the store :tee:
 

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Just got the 22mag version and tried molding some bullets to try reloading for that round, crimper might work just fine but molding bullets with a aluminum mold handle is like frying bacon without a pot holder! Not to mention the bullet cavities themselves are a pos!
BTW, NOE makes a 38gr mold for 22lr that would be LOTS better than the one 22lrreloader makes! HTH
 
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