.303 British military cordite ammo

[André]

A friend presented me with a hundred military .303 British rounds of 1942 vintage in excellent condition. Nevertheless, I didn't feel like shooting corrosive ammo in my pristine bore, so opted for dismantling in order to recover the bullets for handloading. They came out easily with the inertia hammer but I was surprised to find only a bullet but no powder in the hammer body. Inspection of the cases showed these were loaded with cordite, with a cardboard washer (gas check to protect the bullet base from the cordite heat?) between charge and bullet. Bullet weighted 171-175 g and cordite load around 38.0. What really puzzled me was how tightly the cordite strings were packed into the case. I had to pull out the wad, then several strings of cordite with thin tweezers before the rest of the charge got loose enough to come out ?!? I wonder how the production lines operated as they obviously didn't meter by weight/volume, neither could they drop the charge as commonly done with regular rifle powder (sticks, flake or ball).

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[P246]

The cordite was dropped before the case was necked down. Surprisingly the cordite remains stable over the years if stored right. It's the dual compound primers that go. This causes click bangs (I''m told that official British nomenclature...wink) and extreme velocity spreads. I pull it down to but if the primers didn't deteriorate I'd shoot it and clean accordingly.

A nice pile of cordite burns much faster than one thinks, don't ask me how I know.

[browningautorifle]

I've received quite a quantity of that type of ammo from a local antique and curio shop as they have it dropped off with "Stuff" regularly. I'll take it home and prime a fresh case and re use the cordite stick and all. To remove the cordite, just take the bullet out of the inertia puller and give it a couple more whacks to start the stick out. Then the treat is stuffing it back in. I only had one that was so curly-cue I couldn't get them all back, missed a few but all went well. I don't shoot hangfire ammo...

He's spot on about the factory loading of the cordite...

[Catch22]

Handy I stumbled on this, as I have a question that's related.

I have a mess of POF rounds I obtained. For some reason I had it in my head it was boxer primed, but found it wasn't after I pulled the first round.

Now, I've always understood the click....bang was more due to the cordite than the primer. Is that not the case?

With that in mind, I was considering looking at reloading the primed brass with modern powder and using proper data for the projectile. Any reason that can't be done, assuming the cordite is the common issue rather than primers? If it's a primer issue, I guess I've got a bunch to pull for projectiles and scrap the brass.

[WarPig1976]

Handy I stumbled on this, as I have a question that's related.

I have a mess of POF rounds I obtained. For some reason I had it in my head it was boxer primed, but found it wasn't after I pulled the first round.

Now, I've always understood the click....bang was more due to the cordite than the primer. Is that not the case?

With that in mind, I was considering looking at reloading the primed brass with modern powder and using proper data for the projectile. Any reason that can't be done, assuming the cordite is the common issue rather than primers? If it's a primer issue, I guess I've got a bunch to pull for projectiles and scrap the brass.

No, the primers are bad. Pull the bullet the cardboard wad AND the cordite. Stuff it all into a new boxer primed case and you're good to go. My plan is to make blanks or grenade launching cartridges out of the POF brass with the junk primers that have been laying around the shop for years.
https://www.milsurps.com/showthread....l=1#post267098

[Catch22]

No, the primers are bad. Pull the bullet the cardboard wad AND the cordite. Stuff it all into a new boxer primed case and you're good to go. My plan is to make blanks or grenade launching cartridges out of the POF brass with the junk primers that have been laying around the shop for years.
https://www.milsurps.com/showthread....l=1#post267098

That's what I needed to know! Thanks!!!

[Bruce_in_Oz]

If you have a pallet of Mk7 ball with suspect primers, you can salvage the bullets and MAYBE the propellant.

Yo MAY also be able to remove the suspect primers by first "killing' them with a suitable penetrating oil that "should" make them "safe". The best way to get them out is via sudden hydraulic pressure. DO NOT fire off the primers as this will instantly contaminate the brass with the metallic mercury released on ignition. This contamination will immediately start to make the brass brittle.

The BIG problem these days is finding the correct (RWS 6000) lead-based, brass-cupped replacement primer.

Ultimately, depending on your existing stocks, loading skills and sense of humour, it may be better to offload the Mk7 to collectors and start will nice fresh components.

If you want to duplicate Mk7 ball, then you need Mk7 bullets, just like the ones pulled from the suspect ammo. There are several sources of loading data that will provide "close" approximations' of Mk7 ballistics.

Good luck and good shooting.

[Bruce_in_Oz]

Regarding the "big" (.250") copper cupped primers:

The composition of the primers is, (or was originally):

(Lifted verbatim from "Textbook of Small Arms, 1929")

Total weight of priming mix: six-tenths of a grain.

Eight parts by weight of fulminate of mercury. (Mercuric Fulminate)
Fourteen parts .............chlorate of potash. Potassium Chlorate)
Eighteen parts...............sulphide of antimony. (Antimony Sulphide)
One part.......................sulphur. (have a guess)
One part.......................mealed powder. (NOTE: this appears to mean finely ground BLACK POWDER; any advances??)

The mix was pressed into the copper cups, then, an extremely thin TIN foil disc is pressed (carefully) at about 600 pounds pressure into place over the mix.
The final step is the application of a sealing varnish, (best orange shellac). This was done in a machine that used specially shaped "pins" to deposit a droplet of varnish on the foil disc cover.

DEFINITELY NOT a job for the garden shed.

The "Chlorate" components are what provide the "flash" through the "fire-holes" as they were known.

As for inserting the Cordite: the business of filling and then "necking" the case followed on from the beginnings of the .303 cartridge. The original Mk1 round was a Black-powder job. It was NOT filled with "loose" powder, but a SOLID cylinder of compressed black powder Thus, the only way to get this in was to drop it into a "straight-walled" case, (looks a LOT like a .444Marlin), and then form the body taper, shoulder and neck.

Pretty tricky to anneal the neck after the bulk of the case is full of propellant.

Thus, the neck and shoulder region left the factory somewhat "stressed".

It gets better!

The Cordite bundles were cut to a reasonably precise length (1.55-1.60 inches) from a "rope" consisting of about 44 strands and the wad sat on top of this bundle.

The bullet was dropped into this "straight" case and sat on top of the glaze-board wad BEFORE necking. Thus there was hardly a situation of the neck gripping the bullet via some sort of "elastic" action as in the "modern" practice.

The cannelure was supposed to be filled with wax as an atmospheric seal AND "bullet lube" and the bullet held in place by three "stab" crimps that lined up with the cannelure. A final "taper-crimp" was also applied to "close-up" the end of the neck onto the bullet.

The filled and stab-crimped cartridges were then done up in fabric bags and "rumbled" in TURPENTINE to clean them and then, when dry, sent for packing.

As they said in Star Wars; "These are not the loading procedures you're looking for!"

The past is a VERY different country, indeed.

[CINDERS]

Don't bother with the POF I shot it for a while and they all thought I was using a black powder MKIII given the click/bang and all the confetti coming out the barrel do as Bruce says pull the rounds and then see what you can do about the primers. May I suggest you have a couple of inertia pullers as if you have 4-500 rounds to do with the crimp that is on them your going to go through at least one of them if you have a collet type puller I am thinking you may have to have a fair bit of pressure on it to release the projie from the crimp worth a go if it does not mark them to much. I know browningautorifle has tried oil on primers and left them for some time and they still fired and given Jims experience I do not doubt the voracity of his claim as I to was under the impression oil would delouse the primer compound. Jim said he kept the cordite re-primed the cases and carried on wait and see he may chime in with what he did with his MkVII stuff.

[browningautorifle]

wait and see he may chime in with what he did with his MkVII stuff.

That's all I did...was use a fresh case and a new primer. I used the original cordite because I'm cheap. I discarded the cases because they were Berdan primed. I use exclusively boxer cases. I'd use a collet puller to just pull bullets though. I had the whole thing to do and to remove the cordite stick the inertia worked.

If you're removing Berdan primers with hydraulic pressure they shouldn't go off with water being used, should they? I wouldn't bet on oil nullifying them, I had one that soaked for 25 years and it was a good as the first day...