Krag Jorgensen -please read!.

Silfield

Silfield

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We, over here have had a couple of instances recently where K-J's have had catastrophic failures leading to serious injury and there has been a period of time when the MOD has banned their use on all of its ranges pending a safety report. The NRA has issued statements and a report regarding the issues, the link below is worth a read if you own one.

http://www.nra.org.uk/common/asp/content/content.asp?site=NRA&id=1670

Please have a read (and the link in the link takes you to the full report)
Keep safe.
 
reduced load with a slow burning powder ....... not too many rifles out there that fair any better .

this is not a case of one or 2 grains extra powder type of pressure , but rather the type of pressure shown is very similar to when one uses pistol powder instead of a slow burning rifle powder .......

or in this case, detonation caused by a reduced charge of a slow burning powder .
also the 6.5x55 has a bullet with a very long bearing surface which will increase the possibility of the bullet getting stuck in the barrel with too little pressure , then when the bullet gets stuck the pressure spikes and you have a bomb .

the fault here lies between the reloading press and the chair , not the rifle .


thanks for posting :)
 
Thanks, Silfield. That's a very interesting post, not least for the honesty of the reporting by the NRA in admitting that it was still a mystery. I'm inclined to agree with burnt_servo - if the state of the round shown in the die is anything to go by, the reloader was sloppy in the extreme - so who knows how much charge there REALLY was in the one that went KA-boom? I still load each and every rifle cartridge, in eight different loads, by hand and eye, and check every case contents with a penlight before that bullet goes on top. I value my eyes, fingers and guns too much to do otherwise.

Some of us here no doubt remember the world-class shooter and reloader in the USA from a few years back who blew up his Navy Lee, sending the bolt back through his head, a tragedy that actually happened after he had already fired a few overloaded rounds without doing anything about it...

Never get carried way with your reloading, else you just might get carried away because of your reloading.

tac
 
US Krag problems are nothing new.

The U.S. Krags were chambered for the rimmed .30-40 Krag round, also known as ".30 Army." From 1890 to 1893 a 230-grain steel- or cupro-nickel-jacketed bullet was issued, for which no ballistic data is known. From 1894 to September 1899 a 220-grain jacketed bullet loading was issued using 40 grains of nitrocelluose powder, which developed some 40,000 psi and a muzzle velocity of 2,000 feet per second (610 m/s) in the Krag rifle and 1,960 ft/s (600 m/s) in the shorter carbine. In October 1899, after reviewing the experiences of the Spanish–American War, a new loading was developed for the .30 Army in an attempt to match the ballistics of the 7×57mm Mauser cartridge. The new loading increased the Krag rifle's muzzle velocity to 2,200 f/s at 45,000 psi. However, once the new loading was issued, reports of cracked locking lugs on service Krags began to surface. In March 1900 the remaining stocks of this ammunition, some 3.5 million rounds, was returned to the arsenals, broken down, and reloaded back to the original 2,000 ft/s (610 m/s) specification.

http://en.wikipedia.org/wiki/Springfield_Model_1892-99

https://books.google.ca/books?id=tu...EwAA#v=onepage&q=US Krag cracked lugs&f=false
 
US 1892 model Krags also had only one bearing locking lug and sharply squared off action corners while the Austrian Steyr built later Model 1894 actions had 3 bearing locking lugs and radius action corners as well as better steel formulation!

The incident report says that the unused reloaded rounds were only 2/3rds filled with slow burning powder too! A prime candidate for SEE! Also the mentioned damaged Krag's receiver ring ruptured and the locking lugs and bolt held! so the fault was not with the Krags action lock-up design!

SEE is an unexplained pressure excursion which has often blown up guns. It is associated with markedly reduced loads of very slow powders.
Contrary to the ubiquitous old wives tale, detonation is NOT a consideration with fast powders such as Bullseye, no matter how light the charge is or how spacious the case.

The phenomena of Secondary Explosion Effect (SEE) is known to occur only with the slow powders at very low loading densities. Precious little is known about the mechanics of the phenomenon and it is not even known if the expression, Secondary Explosion Effect, is accurate. SEE, despite best efforts of the leading powder companies, cannot be reproduced in the lab, at least in the literature that I have been able to find. Some of the powder companies now are putting notations in their manuals not to reduce CERTAIN loads below 80% loading density. One should note that such notations are for a very limited number of powders and cartridges, such as W-W 296 in the .44 Magnum. Actual documented SEE cases were at densities much less than 80% and with slow powders.

Cast bullet shooters discovered SEE while experimenting with some of the very slow powders. However, they have been using moderate speed powders at much reduced loads since the days of Dr. Mann, with no untoward results. Only the very slow powders exhibit SEE, usually those that were developed for the .50 BMG and magnum rifles such as MR-8700, etc. Recent events posted by Charlie Sharps, "Charles J. Sharps Ph.D" indicates that any powder that is SLOW FOR THAT PARTICULAR APPLICATION, loaded to a significantly reduced powder density, might be suspect.
 
The report attached implies the issue seems to be with guns re-bbl'd after WW2.
Or did I read it wrong?
I've heard about the single lug theory as well. It seems like the K-J is the US version of the Ross MK3...lots of unsubstantiated stories.
P.O. Ackley ground the lug completely off and the handle held the bolt shut with factory equivalent loads.
Unless it's been dycked with ( rebbl'd or tweaked in some mindless way) it'll hold together with a proper loading.
IMO of course. Someone should be along soon to dispute it.
But my Springfield Krag - Jorgenson is still going out deer hunting, it's a marvelous rifle.
 
The report says they found toolmarks or such, that implies that the rebarreljob was done by someone else than a professional gunsmith. It can not be ruled out that it was a contributing factor. An SEE would probably have blown the rifle up anyway. After ww2, a lot of Krags were rebarreled by guys who just bought a new barrel and installed it themselves. If you see marks from a plumbers wrench around the chamber area, you know it wasn't a proper gunsmith job. My first Krag had a .22 cal barrel, installed by my uncle sometimes in the 70's. Years later I tried to reinstall the original barrel. I could screw it in by hand untill it stopped. With the sights in 11 o'clock position! The barrel was completely loose, so the threads on the .22 cal barrel must have been oversize. I trashed the whole thing and bought another Krag.

About the SEE, I just posted this on another forum:
Nils Kvale (Normas famous ballistician) writes in one of his books how he "discovered" the SEE (secondary explosion effect) in the 1950's (the phenomenon, not the name). During the experiments with the "Weatherby powder" (later Norma 205) they got some strange preassure readings that made no sense. Low charges gave overpreassure. He found that the "powder guys" at Bofors and other companys like Winchester etc... could confirm the phenomenon. His theory was that with a low charge of a slowburning powder, and the rifle in shooting position, the powder only filled the bottom half of the case. The flash from the primer would sweep across the surface of the powder, and only partially ignite it. The preassure would push the bullet into the rifling, and when the main charge went off....KABOOOM. The hot gasses from the partially ignited charge bounces back from the bullet and rise the temperature further, wich make the powder burn faster until it litterally detonates.
Too bad his books aren't published in english, it's so much interesting stuff in there. Kvale was an arms and ammo expert in the norwegian army. He was friends with guys like Phil Sharpe, Elmer Keith and such, and in 1952 he started to work for Norma. This book was written in the late 70's, so there's probably more knowledge about the SEE now. Norwegian reloading manuals state that N160 is best suited for the Krag, because it fills the case pretty good.

On swedish forums, they warn against various hard types of bullets in combination with the swedish Mausers tight barrels. This is often the cause of preassure spikes.
This thread shows a M96 that had a blown case. The long debate suggests an SEE or a defective case. He used oncefired Norma brass, 120grains Barnes X bullet, and Norma MRP powder. He doesn't say what charge, but say it was above the recomended starting load. The shooter and spotter got their faces full of gass and particles, but were not injured.
http://forum.robsoft.nu/viewtopic.ph...enspr%E4ngning
 
When I see a report coming out warning suggesting that a 120 year old firearm has suddenly been discovered to be dangerous, my instincts are always "Operator Error".

So in the end the cause was deemed to be inconclusive, but the suspicion is that it was improperly loaded ammo, and/or amateur gunsmith modifications. Hardly a surprise.

That's a whole lot of fuss that the NRA went through, but I guess in the UK they need to actively justify the support they receive. Sadly the "less than thoughtful" have already concluded that the Krag Jorgensen is "dangerous" and will happily pass on that myth for decades based solely on that report. They are plenty of that ilk that follow CGN - for many of them just the dramatic title of this thread "Krag Jorgensen -please read!" is all "evidence" they need.
 
It is not unusual to see Norwegian Krags rebarrelled in Europe to non-military calibers; I have seen some in .243 Winchester. Probably something to do with restrictions on military firearms.
The reduced load of slow burning powder failure has been observed often enough that it is a recognized hazard, even though not well understood.
Another issue, which I did not see mentioned, is how a firearm handles the release of high pressure gas in the event of a catastrophic failure of the cartridge case. The cartridge case is the weakest element; brass will fail long before steel. Once the case fails under excessive load, the high pressure gas will escape. How the firearm handles the escaping gas then becomes an issue. Obviously the Krag didn't handle the release well at all. I assume that the receiver is most likely case hardened mild steel. It shattered.
 
tiriaq said:
It is not unusual to see Norwegian Krags rebarrelled in Europe to non-military calibers; I have seen some in .243 Winchester. Probably something to do with restrictions on military firearms.
The reduced load of slow burning powder failure has been observed often enough that it is a recognized hazard, even though not well understood.
Another issue, which I did not see mentioned, is how a firearm handles the release of high pressure gas in the event of a catastrophic failure of the cartridge case. The cartridge case is the weakest element; brass will fail long before steel. Once the case fails under excessive load, the high pressure gas will escape. How the firearm handles the escaping gas then becomes an issue. Obviously the Krag didn't handle the release well at all. I assume that the receiver is most likely case hardened mild steel. It shattered.
Click to expand...

The suggestion that it was SEE seems unlikely to me, as AA2520 is really not a slow(er) burning rifle powder (like 4350), but is what most would consider a "medium".

The moment I saw the bulged shoulder on that loaded round I thought: "pinched neck". Regardless, that bulged shoulder has all of the hallmarks of a novice, ignorant and careless reloader.

Any suggestions as to possible cause (and we can never know for sure) should, I think, point to the ammunition, not the rifle.
 
Case hardened mild steel will just split open like a banana, that's why old Mauser's if they ever explode, they seldom shatter as their centre is soft and mostly have a controlled splitting open of the action with the bolt holding. The full heat treated steel becomes brittle like the early Springfield rifles were, they shatter when they let go!

M1903LN764040shatteredreceiver.jpg
standard.jpg
 
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