Wow! Overpressure Russian Ammo!

[AGE]

Lugercollector and others! I'm also posting this in the Corrosive Ammo discussion.

WOW!!! IT HAPPENED TO ME TODAY. As I remember, there was an overpressure Russian ammo case discussed on the old forum and now I have my own.

I had bought some Wolff and Silver Bear ammo before reading of the overpressure case back about April or May. Anyway, I've been shooting this stuff up in my S&W 3914 since I didn't want to risk it in my Luger.

After about 30 uneventful rounds shooting the Silver Bear ammo the S&W locked up tight after firing without ejecting the case. I didn't notice a particularly loud round, but anyway I had a hard time clearing the gun. I had to pound a rod into the barrel (that was a loose fit in an empty case) while pulling hard on the slide. Finally, the case came out. The fired case was not ruptured, but would not go back into the chamber. It is much bigger in diameter than a normal fired case (maybe .007 to .010"), I don't have a micrometer handy at the moment.

WATCH OUT FOR PROBLEMS WITH RUSSIAN AMMO. My S&W doesn't seem to be damaged--the barrel looks OK under close examination after disassembly and cleaning. I'll test it out probably in a week or so with Walmart Winchester and then maybe some Federal hollowpoints.

[unspellable]

In some cases it doesn't take much to do it!

For the 30 Luger, the Winchester handloading guide lists 4.2 grains of 231 at 1085 fps from a 4.5 inch test barrel as running 25,500 CUP and calls it a maximum load. This is well under even the low SAAMI maximum pressure. I started wondering why such a light load and ran some calculations.

Admittedly, this is an "on paper" calculation, but if we up it 0.1 grain, usually the smallest increment a handloader will use, we are over 28,000 CUP, and at 4.4 grains we have reached 28,542 CUP, over the SAAMI maximum. Now you better believe Winchester will observe the SAAMI maximum even if it is low. But the point here, is that we have a case where a very small increase in powder charge drives us from a low pressure to over maximum and the middle ground went by too fast to notice if you blinked.

Just for laughs, a double charge, (Don't know if it would fit in the case or not.) would produce a muzzle velocity of 4340 fps provided the gun stayed together long enough for the bullet to reach the end of the barrel. This seems extremely unlikely as the pressure when the bullet has traveled less than an inch would reach 408,000 CUP. It would make a genuine collector's piece out of the gun. I would want at least thirty feet of string for pulling the trigger. This kind of pressure would be hand grenade country if the gun stayed together long enough for the pressure to get that high. Actually, I would expect the gun to blow before it got past 100,000 CUP which explains why blowups usually (Note: usually...) don't kill the bystanders outright. I am talking an out and out blow up here, not split cases, blown primers, or busted extractors and breechblocks that happen at pressures below 100,000 CUP.

[Herb]

I tried to warn you guys about that Russian ammo. This is what it did to my C96 Bolt! <img src="graemlins/c.gif" border="0" alt="[ouch]" />

[unspellable]

Herb,

What's the full story on this failure? It doesn't look like a case of simple overpressure. Calls to mind things like excessive impulse, weak recoil spring, fatigue cracks, etc. I would expect simple overpressure to take off the lower part of the breech face or the extractor. Did the primer let go? What did the case look like?

Of course overpressure can also be like lightning and do as it damn well pleases.

[Herb]

Unspellable, I really have no Idea what happened. A friend was shooting it and on the third shot the front piece of the bolt flew into the air with the spent casing which I have not found. I am not a metallurgist but my guess was crystallization of the steel as it appears to have neen 'sandblasted' on the broken edges. If there was a pre-existing crack it was not visible at the time. The bolt appeard to be in perfect shape. During my search for another bolt one guy at a gun shop that sells quite a few C96's said that the russian ammo is made for russian sub-machine guns and is much too hot for anything else. He sure got my attention.

[unspellable]

Herb,

Crystalization or some such flaw probably played a role here. I wonder if there is a simple and practical way to see it coming before things come apart. Any metalurgists looking in?

I've always been very dubious about the oft heard stories of various sorts of pistol ammo loaded for sub-machine guns. It would create a nightmare for logistics and supply in any military organization, not to mention there would always be some fool who would mix the ammo.

A point of interest is that most service pistols are recoil operated, while most submachine guns are blow back operated. So the impulse is what counts in operating the pistol while the pressure curve is what counts for operating the sub-machine gun.

It is also interesting to note that a good sound C96 chambered for 7.63 Mauser will chamber and fire a 9 mm Parabellum cartridge without coming unglued. Imagine the overpressure you run up swaging a 9 mm bullet down to 7.63 mm! (This is a highly not recommended practice! I'd heard of it before, but when I came across an actual case, repeated firing of the 9 mm Parabellum in the 7.63 mm C96 had resulted in the appearance of cracks and an obviuosly dim future for the C96.)

[wterrell]

Metalurgy was and is (to a large extent today) an art. Whenever these pistols were made, the exact composition of the ore and alloys was not known. Experience was the standard by which the compositions were selected. Hopefully, today the materials used in pitols is much better.

[unspellable]

Herb,

Crystalization or some such flaw probably played a role here. I wonder if there is a simple and practical way to see it coming before things come apart. Any metalurgists looking in?

I've always been very dubious about the oft heard stories of various sorts of pistol ammo loaded for sub-machine guns. It would create a nightmare for logistics and supply in any military organization, not to mention there would always be some fool who would mix the ammo.

A point of interest is that most service pistols are recoil operated, while most submachine guns are blow back operated. So the impulse is what counts in operating the pistol while the pressure curve is what counts for operating the sub-machine gun.

It is also interesting to note that a good sound C96 chambered for 7.63 Mauser will chamber and fire a 9 mm Parabellum cartridge without coming unglued. Imagine the overpressure you run up swaging a 9 mm bullet down to 7.63 mm! (This is a highly not recommended practice! I'd heard of it before, but when I came across an actual case, repeated firing of the 9 mm Parabellum in the 7.63 mm C96 had resulted in the appearance of cracks and an obviuosly dim future for the C96.)

[unspellable]

How is it that I send a post once and it shows up twice?

[AGE]

Guys,

I am not a metalurgist, but I am a mechanical engineer. Some materials (like concrete, glass, etc.) are brittle and fail or break without a lot of distortion or stretching. Other materials are ductile and distort a lot (like copper) before breaking. Steel, as Wes has said, was not well understood 90 years ago. A lot more is known today and the various alloys in use generally behave much better in service.

Steel is known to become brittle at lower temperatures and there is actually a transition temperature where the behavior changes. Sometimes the transition temperature is perhaps 30-50 degrees F. Also the hardness that many people like to brag about makes a steel more brittle.

The rough surfaces in the C-96 bolt failure look like some sort of brittle failure to me (but the picture shown above doesn't really allow one to make an official conclusion). Fatigue failures can look like brittle failures with little deformation, but this usually requires over 100,000 cycles--not likely in a semi-auto firearm.

The C-96 bolt failure looks to me like the result of using poor steel, perhaps on a cool day (but who knows?). Herb, did this failure happen in Utah in the winter?

Fortunately my S&W is only a few years old and, hopefully, uses modern steel. The barrel looks like stainless steel which is usually very ductile without transition to brittle behavior at any likely service temperature.

Also, the Russian ammo seems suspect and any gun, new or old, poor or excellent, is more likely to fail if subjected to excessive pressures.

Another fly in the ointment is the fact that the Russian ammo uses steel cases rather than copper alloy used in domestic ammo. I don't know why that might change things, but again, who knows?

[Herb]

Tacfoley, my C96 was 7.65 not 9mm. In fact I think the russian ammo might have been 7.62 but sold as great for shooting in a C96. I don't advise it even though there may have been a defect in the bolt that went unnoticed as it appeared to be nearly unused, really sharp and clean inside and out. It was, if I reacall, a generic package, not the Wolf or any other named brand that has recently been coming in from Russia.

[max2cam]

Hmmm...you guys are convincing me to buy as my next batch of 9mm non-Russian ammo.

I have 500 rounds of Russ. 9mm from "Unitary Enterprise Production Association Ulyanovsk Machinery Plant" 124 gr. steel-case ammo from Century. Works fine in the right Luger mag.

But instead of getting more, I'll get PMP instead in this order I'm putting together. I was trying to decide anyway. This as good a way as any I suppose....

[Herb]

Max2cam, somewhere on the Forum in the last couple of days someone posted that Wal-Mart sells a 'brick' of Winchester 9mm for a good price. The next time I get around one I am going to check that out. Never having done it but it would seem to me that steel cased bullets would be kinda hard on the rifleing versus copper. Have you noticed your rifleing 'going down range'?

[Dwight Gruber]

Wal-Mart sells Winchester bulk-packed 9mm for a few cents shy of $11/100 rounds. It seems to be a bitmore powerful than most commercial 9mm, a good match for a Luger. I shoot 700 rounds or so a month of this stuff with virtually no operating problems in the three Lugers I shoot regularly.

--Dwight

[wterrell]

I must discard and throw out my bullets every so often because they get old. As a child, my shells and bullets were precious, so I developed an aversion to shooting. I have suffered for it several time in adulthood as a covey of quail exploded and I would pantomime a shot because of old shot shells.

I have bought Winchester in bulk, and have thrown out Winchester in bulk. Now I purchase an expensive box of bullets and somehow don't feel as bad about throwing out fewer rounds.(?) <img src="graemlins/bigok.gif" border="0" alt="[thumbsup]" />

[Steve Richards]

I have read too many horror stories about comercial ammo for the Mauser broomhandle. Unless I can get stuff that is marked specifically for those guns, I stick to my handloads. I have had dealers tell me their ammo marked for Tokarevs was safe but I am too chicken to try it. I purchased a complete Lee turret- head loading press, 500 brass, 500 bullets, primers, and powder for the price of 500 rounds. A nice mild load in an old gun and I feel quite safe. <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

[max2cam]

I've tried Winchester 9mm and my Luger doesn't like it. Sounds like others have had better luck with it.

I said previously that I have steel-cased Russian ammo and it is, but just now I put a magnet to the bullet too and that attracts a magnet as well. The bullet core is lead.

It's my understanding that the steel used in steel jacketed bullets is soft and thin and barrel steel is tough and hard. But I'm sure that the general concensus is that shooting steel jacketed ammo in a Luger ist "Streng Verboten!"

[unspellable]

Steel bullets will not be a problem unless they are bad steel bullets. Steel cases can cause extraction problems. The steel case was originated as a solution to war time brass shortages. The steel jacketed bullet, on the other hand, was used in sporting arms from before the turn of the century. (the 1899 -1900 turn) A lot of game rifles used steel jacketed bullets. When I say game rifle, I mean a double rifle, not half a rifle with only one barrel. Replacing the barrels will put the cost of a very nice P-08 in the pocket change category. The principal cause of barrel wear on many of the older rifles was overly enthusiastic cleaning.

[unspellable]

Steel bullets will not be a problem unless they are bad steel bullets. Steel cases can cause extraction problems. The steel case was originated as a solution to war time brass shortages. The steel jacketed bullet, on the other hand, was used in sporting arms from before the turn of the century. (the 1899 -1900 turn) A lot of game rifles used steel jacketed bullets. When I say game rifle, I mean a double rifle, not half a rifle with only one barrel. Replacing the barrels will put the cost of a very nice P-08 in the pocket change category. The principal cause of barrel wear on many of the older rifles was overly enthusiastic cleaning.

[Roadkill]

I heard somewhere never to shoot old steel cased ammo because of the projectile sticking in the rusted steel cases resulting in overpressure and commensurate blowup. There has been a lot of WWII .30 carbine and .45 steel cased available still in sealed cases. Good, Bad, or Ugly?

RK