Mauser 7x57 Blow-ups from Kortnek Ammo in the Boer War

[303Guy]

Does anyone know the truth behind this?

[Baron von Trollwhack]

Over the years, in using a number of number of books and similar having minor references to this short-necked ammo, I've never seen a reference to it causing rifle blowups. While I have seen numerous pictures of the ammo, I've never actually seen any. However, it appears to me to be the 7.65 Belgian Mauser case length used in a 7 X 57 Mauser loading, thus the shortness. You may look for data in one of W.H.D. Bell's Mauser books.

BvT

[Hang Fire]

I have done a lot of reading about the 2nd Boer war and recall nothing about 7mm ammo blow up's.

As the war progressed and British embargo tightened, the Boers were rapidly reduced to mostly using captured Enfield Rifles and 303 ammo.

[Multigunner]

There were 93 Mauser blow ups when using 7mm Kortnek ammo.
From what I've read the short 7mm cases were manufactured before the case design was finalized with the standard 57mm length. These were in storage and sold off when the Boers and their supporters were buying up ammo anywhere they could get it.

Another factor was home made smokeless powders the Boers made at a local dynamite factory.

Whatever the case the gap left by the short neck sometimes allowed the steel jackets to expand into the gap and strip away the base of the jacket. When the next round was chambered the bullet telescoped into the ring of jacket metal left jammed in the chamber neck. On firing pressures were high enough to blow out the breech.

To try to avoid this situation bullets of Kortnek cartridges were given a coating of a thick green bullet lube. The lube forming an incompressible layer between the jacket and the gap at the neck.

Since fatal infections of bullet wounds was commonplace in Africa the British thought the evil green appearance of the lube was some sort of poison and executed some Boers found with this ammo.

In part they may have been correct in assuming the green lube promoted infection. Tests by a British surgeon proved that germ cultures used to coat .303 bullets survived being fired into animal flesh and could cause infections. It had been believed that heat of passage through the bore due to friction would kill germs. Germs can be caught up in greasy compounds.

[303Guy]

Thanks for that. Multigunner, might I ask where you found that information? I read an article some thirty years ago in which there was no conclusion as to the cause or even whether the kortnek was responsible. My understanding on the origin of the kortnek was that it was 7.62x53 brass that was neck sized to 7mm and loaded for the Boers as a contingency. It had been suggested that heat damage may have been the cause. If the ammo was transported through Mozambique by ox wagon it could have been exposed to direct sun which can be hot enough to fry eggs on rocks or car hoods. I've heard of military 6.56 NATO ammo blowing out the magazine during the bush war which was fought in the northern bush regions and that was attributed to heat degradation but maybe from fire.

I had forgotten about the Boers using captured Lee Enfields. Apparently they didn't find them inaccurate if I recall.

I'm just wondering where I would find Bell's books? I suppose the local library would be a good place to start.

[Multigunner]

Thanks for that. Multigunner, might I ask where you found that information? I read an article some thirty years ago in which there was no conclusion as to the cause or even whether the kortnek was responsible. My understanding on the origin of the kortnek was that it was 7.62x53 brass that was neck sized to 7mm and loaded for the Boers as a contingency. It had been suggested that heat damage may have been the cause. If the ammo was transported through Mozambique by ox wagon it could have been exposed to direct sun which can be hot enough to fry eggs on rocks or car hoods. I've heard of military 6.56 NATO ammo blowing out the magazine during the bush war which was fought in the northern bush regions and that was attributed to heat degradation but maybe from fire.

I had forgotten about the Boers using captured Lee Enfields. Apparently they didn't find them inaccurate if I recall.

I'm just wondering where I would find Bell's books? I suppose the local library would be a good place to start.

There are a number of books on the Boer war written within months of the conflict by men who were there available as free downloads at the Internet Archive.
The Internet Archive is a great resource.

Theres been plenty of speculation on the source of the Kortnek cases. Best explanation I found was that the original 7MM Mauser design was based on the 7.65 case. The Spanish had at first been offered a 7.65 rifle based on the 1891 action with new features later carried over to the 1893 rifle.
The long 7mm Bullets required a long neck for support so the cartridge design was changed before Spain accepted the 1893 rifle.
Others speculate that drawn and trimmed brass blanks meant for the 7.65 were diverted to be finished out as 7mm cases.
Since cartridge company records are not available, and even the source of the cases is in doubt we may never know.

The Boers would use anything that would shoot. When they had Mauser rifles and good ammo they out ranged the British .303 rifles, but when using the .303 they were on equal terms.
The main accuracy problem the Lee Enfield and Lee Metford rifles had in those days was that when sighted in at the factory in England then shipped to Africa or India the Zero was found to have shifted several minutes in the horizontal plane.
New rear sight leafs were shipped out to compensate.
Makers of big Game rifles had found the same problem with other rifles in several chamberings that used Cordite. They began reducing charges of ammo shipped to India and Africa.
Charges safe enough in 60 degree F climates were dangerously overloaded when ambient temperatures were often twice that high.
Tests by the RAF in later years revealed that the temperature inside the standard ammunition case could exceed 160 degrees at mid day in the Indian northwest Territories.
British practice was to wrap ammo boxes in blankets to insulate them, and store these in caves when possible.

There were improvements in the design of Bolt Heads after many broke off when heat damaged ammo was used.

The Compressed black powder charge of the Lee Metford cartridges could fragment on rough handling, causing numerous case blow outs due to detonation.

[303Guy]

Thanks. OK, on the theory that the bullets upset in the unsupported neck, there is someone out there who says he has fired many kortneks with no ill effect. I'm not sure where he got the kortneks from. Fairies at the bottom of his garden maybe? He said the Mauser blow-ups were a myth but I know blow-ups did occur as I've seen excerpts from those same early authors you mention.

Anyway, I suppose with heat damage or maybe simply hot ammo fed into a hot rifle made even hotter by firing could raise the pressure sufficiently to upset the bullets where under normal conditions they might not upset.

Found the archives and the books on the Boer war. Thanks for that. I don't actually read much - haven't read a book for about thirty years.

[Multigunner]

Thanks. Ok, on the theory that the bullets upset in the unsupported neck, there is someone out there who says he has fired many kortneks with no ill effect. I'm not sure where he go the kortneks from. Fairies at the bottom of his garden maybe? He said the Mauser blow-ups were a myth but I know blow-ups did occur as I've seen excerpts from those same early authors you mention.

Yeah there are many self styled experts out there who simply make stuff up.
If Kortnek cartridges were still to be found in firing condition it would be a miracle. A few survive in cartridge collections.
Not all 93 Mausers had blow outs, and a rifle might handle a number of these cartridges before it did suffer a blow out. A replica of the Kortnek using a bullet with jacket less prone to jacket separation might reduce probability of such accidents, but no such bullet was available at the time. Some attempts were made using bullets with red copper jackets but this did not prevent jacket stripping. Only the incompressible lube worked to prevent jackets bulging into the gap and stripping away.

Pretending something previously proven to be unsafe is perfectly safe because you haven't peeled your own face off like a Halloween mask just yet is a dis service to other shooters.

One of those gurus of which you speak had similar arguments, and claimed to have published articles on the subject. He later admitted he lived in Saudi Arabia, where he was not permitted to own firearms, and had owned only one firearm which was some off brand revolver.
Another was very vocal about gun ownership in India, trying to give the impression that civilians could own any type of firearm. Which of course was balderdash. He made a lot of ridiculous claims about the Enfields , pretending to have wide experience with that rifle. Turned out his only experience with the Enfield was occasionally being allowed to fire an old SMLE belonging to the local police department, he had never been able to get a permit to own an Enfield. Almost all Indian firearms permits are limited to .22 caliber rifles and shotguns. Civilian handgun permits are limited to .32 handguns.