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.Originally Posted by 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/grade...position-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.
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.
Do you have any preference with the lacquered case or the gray polymer coated ones?
These men and their hypnotized followers call this a new order. It is not new. It is not order.
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
What doesn't kill you makes you stronger - or else it gives you a bad rash.
Venison is free-range, organic, non-GMO and gluten-free
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.
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.
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| BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
| BR | Bench Rest | M | Magnum | RN | Round Nose |
| BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
| C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
| HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
| PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
| LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
| GC | Gas Check |
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