My steel case 7.62X39 cast boolit project

[6622729]

I just wanted to share my steel case cast boolit project. There is so much misinformation out there I feel like I need to counter it.

My rounds are Berdan primer Tulammo steel cases in 7.62X39. I use a hydraulic method of easily removing the old primer. They pop right out under water pressure. Then I lube and size in Lee dies just like any other brass. I see no evidence that this is hard on the dies and the steel forms just as easily as brass. Replacing the primers are no different than installing boxer primers in brass cases though they might be a little more finicky to get them to seat. I am using correct 7.62 primers so I'm not having to get into converting cases to boxer or gluing in an alternative modified primer. The boolits are powder coated NOE 155gr and Lee 160gr cast from approximated Lyman #2 alloy and water dropped. In my case they are sized to .311. They are copper gas checked. Currently my production load is 19.5gr Accurate 1680. For my 200yd plinking it is as far as I have had to develop the load. I can sit at a bench and drill an 8" diameter steel plate at 200yds, shot after shot. That's plenty of fun for me.

I want to dispel three things I keep reading from people who obviously do not load these steel cases...

1) Removing Berdan primers is silly easy though it is a separate step. It doesn't have to be complicated, slow or messy.

2) Sizing mild steel cases in hardened steel dies does not cause excessive wear. Even if it did, it would take a long time to cause wear and dies are cheap.

3) Steel cases do not instantly work harden. I have some cases I have reloaded 10 times and are still going. Some split when fired as a factory load. I suspect this is a quality control issue with the original Russian manufacturing. I have found that if they don't split in the first two uses, they're going to be good for many reloads. The failure mode for me is always that the case mouth harmlessly splits.

* I'm sharing this information just for fun and to counter some bad information out there. This post is not meant to be instructional on how to load steel cases and In no way am I suggesting you do so.

Be aware that I am shooting these rounds exclusively in a couple of bolt guns. I am not sure I would do this in a semi auto. Hopefully others who load this round and maybe use it in a semi auto can add their experience to the thread.
310886
310887

[Bigslug]

Neat! So what is your hydraulic method of Berdan primer removal that is neither complicated, slow, or messy?

[Grayone]

Neat! So what is your hydraulic method of Berdan primer removal that is neither complicated, slow, or messy?

I am interested in learning more about this deprimeing and reprimeing process also.

[deces]

Nice job, I need to get on a lathe again for my 7.62x39 ammo project.

[Joby]

I experimented with the .223 steel cases long ago for grins. After 10 reloads with jacketed 55 grain and 24.0 grains of WC844 in 50 cases without any problems.
They were boxer primed so I didn’t have the Berdan primer step.
I would be weary of rusting and pitting and therefore causing a stress riser and resultant case failure. Especially with storage times. Otherwise they worked fine.

UN blue bullets eh. Maybe sooner than ya think.

[Texas by God]

I have loaded steel case Boxer primed .45 ACP with 200 gr SWC over a stiff load of Power Pistol. I use them for hunting so I don’t have to look for my fired brass in the brambles. Easy come, easy go.


Sent from my iPhone using Tapatalk

[6622729]

I used this guy's drawing as the basis for my tool. I changed a lot of dimensions but it's essentially the same tool. They work great!

https://www.youtube.com/watch?v=ppZ7yHbr5qk

[6622729]

Repriming is the same as any other primer installation. I use genuine Berdan primers for 7.62X39. They fit in the large rifle primer cup on my Lee single stage press.
I just finished the 800th primer so this is not a new project to me. 800 rounds loaded one at a time in bolt guns is a lot of shooting. [smilie=w:

310898

[405grain]

I'm skeptical of cast loads in steel case 7.62x39. With full power jacketed loads the steel case has enough pressure to expand and seal the chamber. With lower power cast loads I'm wondering if there's enough pressure for the steel cases to seal.

[mdi]

During my experimenting with Berdan primed cases (7.62x39), I just used a wooden dowel slightly smaller than the case mouth, and my "Lee Loader mallet". Got some water on the bench but further experimentation would have eliminated 99% of the mess...

[6622729]

"I'm skeptical of cast loads in steel case 7.62x39. With full power jacketed loads the steel case has enough pressure to expand and seal the chamber. With lower power cast loads I'm wondering if there's enough pressure for the steel cases to seal."


What is your sketicism based on? Have you tried it? I'm shooting these loads. I'm shooting these at 1800fps and hammering the 200 yard target with 155-160 grains repeatedly. You don't have to believe it but if you're not doing it, please don't tell other people it doesn't work because it does.

[Der Gebirgsjager]

Great post and information, 6622729 (hope I got the numbers right!).

Back in the 1960s when I first got into reloading I had access to lots of WW II surplus G.I. .45 ACP ammo. Can you believe...I still have a couple of boxes! Well, they had steel cases, but regular Boxer primers of course. I wondered why, being a Po' Boy at the time, they couldn't be reloaded. Everyone I asked about it said, "No, no...you'll wear out your dies." But I had to try a few just to see if it could be done, and found that it wasn't much different than reloading brass cases. It also occurred to me that it would take many boxes of steel case reloads to wear out the dies, and I'd come out quite a bit ahead when comparing the price of a new set of dies to the cost of that much store bought ammo. It went along fine for awhile. I did experience a few split case mouths, and just tossed them, but what eventually stopped me from reloading them was that they were rusting inside, some badly, and I began to fear more severe case failures. Today, looking back on it, I think the internal rusting was from the corrosive WW II primers, and I'm pretty sure the Berdan primers the Rooskies are using are non-corrosive, so I can't think of any negatives at all about your project. I never did wear out the dies.

DG

[6622729]

In regards to potential internal rusting, I deprime in water with a little bit of dish detergent in it. I then rinse and wipe down the outside of each case then lay them on a towel to dry. If it's hot and sunny out the sun dries them inside and out quickly. Indoors they'll dry fine just laying around or like right now, I have a batch of 50 drying in front of a bathroom heater. At most I see a slight bit of flash rust inside. Certainly nothing structural. Once loaded and in an ammo box I have yet to see any rust appear on the exterior which I have to admit does surprise me. Between the original coating, the Imperial case wax and storing them indoors, rust hasnt been a problem.

[405grain]

6622729: Don't take it personal. I had doubts because I've seen brass cases with blow back on the neck and shoulder area before due to the pressure not being high enough to seal the case. Steel cases are stronger than brass, so it would take more pressure to cause them to seal good. If you say that you're getting good results with steel cases then I take your word for it.

[6622729]

6622729: Don't take it personal. I had doubts because I've seen brass cases with blow back on the neck and shoulder area before due to the pressure not being high enough to seal the case. Steel cases are stronger than brass, so it would take more pressure to cause them to seal good. If you say that you're getting good results with steel cases then I take your word for it.

Why do you think steel cases are “stronger” than brass cases?

[Outer Rondacker]

A case is only as strong as the chamber it is set into. My 2 cents. I guess I should keep my mouth shut about reloading some aluminum 9mms back in the day just to see if I could.

[405grain]

"Why do you think steel cases are “stronger” than brass cases?"

Because of material properties. https://www.engineeringtoolbox.com/young-modulus-d_417.html

[mdi]

Hmm. I was (am) under the impression that steel cases are made from a soft steel alloy, not as hard as a "Made in China, Harbor Freight wrench" or butter knife. Much the same mailability as cartridge brass. I have fired a few thousand steel cases ammo in my SKS and AK and never noticed any soot from cases not sealing chamber. I don't bother to reload steel cases, not from the "internet wisdom", but because I have enough brass cases to last me a few decades, but I did as an experiment several years ago.....

[barnetmill]

If berdan primers were handy I would reload berdan primed cases. I have just a few very old berdan primers on hand and those are just for loading some rare case that happens to be berdan and happens to be the right size the cases.
I am not sure about full length resizing steel bottle neck cases. If you full length resize them, and the powder charge is sufficient they will work in an AK, but there might be quite a bit of residue if you use lead bullets. I have only reloaded 7.62x54 and used in a mosin rifle. I only neck sized and I had the wrong primers so they were routinely pieced by the firing pin. Those cases would fit a .254" shotgun primer that was not intended to be used in a rifle

[6622729]

A case is only as strong as the chamber it is set into. My 2 cents. I guess I should keep my mouth shut about reloading some aluminum 9mms back in the day just to see if I could.

Yes. The case just holds it all together to get it sealed into the chamber.

I have no experience with aluminum cases, but…..lol.

[6622729]

"Why do you think steel cases are “stronger” than brass cases?"

Because of material properties. https://www.engineeringtoolbox.com/young-modulus-d_417.html

What alloy of brass and alloy of steel are used in rifle cases? I don’t know either. I do know the alloy chosen has to be mailable enough to be drawn into the shape of a case. I know that the alloy the Russian’s chose for the Tulammo 7.62x39 cases has been lending itself well for multiple reloads and creating accurate cast lead rounds.

[405grain]

If it is working for you that's good enough, I believe you. To answer your question: the steel case material is probably SAE/AISI 1008, or a similar alloy. This has better mechanical strength than SAE/AISI 1005, and is usually used for press forming operations, ie: drip pans and valve covers in automotive applications. It's carbon content is too low for it to be heat treated. It typically has a yield strength of 41,300 psi, and a tensile strength of 49,000 psi. Here's a page on it's chemical make up and mechanical strengths & applications.
https://blog.thepipingmart.com/grades/sae-aisi-1008-properties-composition-uses/

Cartridge brass is almost always C26000 yellow brass, which has a composition of around 30% zinc and 70% copper. Unlike steel, which returns to it's normal state unless its yield strength is exceeded, brasses deform plastically until they fail when their tensile strength is reached. Based on the amount of temper C26000 brass usually has a tensile strength of between 47 to 52 thousand psi. Here's a link to a sheet that discusses C26000 mechanical properties; https://alloys.copper.org/alloy/C26000

The engineering involved in pressure forming an ammunition case inside a firearms chamber to form a gasket seal is involved. Please don't ask me because it would be like trying to explain how a watch works, only more complicated. There are lots of dynamics involved here, and this is a reloading and bullet casting forum, so I'd prefer to keep it light and not go there. At one point in my career I was working at one of the National Laboratories finding solutions to problems with liquid propellant artillery, and I've got to tell you, it's beyond normal levels of boring. If your steel cases are working for you, I stand corrected, and wish you many happy days of shooting.

[thump_rrr]

What is your reason for choosing steel cases over boxer primed brass cases?
Availability of the steel cases?
Availability of berdan primers?

I don't shoot that much 7.62x39 but I do manage to find a few once fired boxer primed brass cases every time I go to the range.
Just yesterday I collected 6 pieces. Sometimes I walk away with 20.

[6622729]

What is your reason for choosing steel cases over boxer primed brass cases?
Availability of the steel cases?
Availability of berdan primers?

I don't shoot that much 7.62x39 but I do manage to find a few once fired boxer primed brass cases every time I go to the range.
Just yesterday I collected 6 pieces. Sometimes I walk away with 20.

Oh, I chose the Berdan steel cases for my cast loads because I kept reading how it wasnt possible. Then I found a couple people who were doing it successfully. I like doing stuff off the beaten path. I was fortunate enough to be able to buy a quantity of 7.62x39 Berdan primers and my lead alloy supply is ridiculous. I started this project when small rifle primers were non existent. This allowed me to cast, reload and continue to shoot rifle without depleating the srp inventory. Now its routine and my primary rifle shooting. I reload 223 and 300bo in brass boxer. The 300bo shares the same cast boolits as the 7.62 project except I have an additional awesome 220gr low supersonic load in 300bo.

[deces]

Do you have any preference with the lacquered case or the gray polymer coated ones?

[Bmi48219]

During my experimenting with Berdan primed cases (7.62x39), I just used a wooden dowel slightly smaller than the case mouth, and my "Lee Loader mallet". Got some water on the bench….

In the mid-60’s dad bought a Swiss straight pull rifle for $10 and a case of surplus berdan primed 7.5 Swiss ammo for another $10 at a community gun show. We deprimed them in a coffee can of water with a dowel and mallet. He found a supply of Berdan primers and a Lee-type reloading kit at another show.

[WRideout]

In the mid-60’s dad bought a Swiss straight pull rifle for $10 and a case of surplus berdan primed 7.5 Swiss ammo for another $10 at a community gun show. We deprimed them in a coffee can of water with a dowel and mallet. He found a supply of Berdan primers and a Lee-type reloading kit at another show.

After reading about converting Berdan cases (is that like Catholic to Baptist?) I acquired a stock of 7.5 Swiss empty cases for my K31. I used a friend's lathe to do the machine work, and figured out a way to make the pocket smaller. What I didn't count on was that the depth of the pocket was shorter than the primer. Consequently I broke both of my Lee round tray priming tools; many tears shed.

At the time, I could not guess where to obtain the correct Berdan primers. If I could have gotten them, life would have been wonderful. Now I wish I had just waited to get them when available. Brass Berdan cases have gone to the salvage yard to be resurrected in another life.

Wayne

[Brassmonkey]

A case is only as strong as the chamber it is set into. My 2 cents. I guess I should keep my mouth shut about reloading some aluminum 9mms back in the day just to see if I could.

lol you too? Spotted a few Al cases that were boxer primed, hmmmm what's the worst that could happen?

Too many split during seating to fuss with again. I like the way Al 9 feels and feeds in drum mags.

[6622729]

Do you have any preference with the lacquered case or the gray polymer coated ones?
Well, Im shooting both. One doesnt seem to be more accurate than the other. They both seem to last for many reloads. The laquer cases require significantly less force when run through the dies. As I lube both with Imperial case wax, my guess is that it is a different steel and not the finish.