Paper Tube (Cardboard)

Gentlemen, a friend has a 16 bore pin fire shot gun and as this type of ammunition is obsolete i am trying to recreate pin fire cartridges for him. The original cartridge heads are made of pressings which sandwich a paper tube and a base wad to form the case. Some cases are rimless. I have designed a head to which I intend to fit the tube, either paper (card) or plastic with adhesive. The outside diameter of the tube is ) 0.75" and the tubes vary between 0.5 mm and 0.68 mm thick, The design can easily be modified to accommodate either wall thickness. I would prefer purely for aesthetic reasons to use new tube either paper (preferred) or plastic - the question is where can i obtain the tube? Thank you in advance for any assistance which would be most welcome. Robert Butler

3-D printed?

Make a suitable mandrel, spiral wrap with strips of glue and paper. When dry trim ends and slide off mandrel.

Martin C

Spray the mandrel with silicone polish first to stop the paper sticking

.

... Or save some effort by using gummed paper tape : **LINK**

https://www.agritelonline.co.uk/gummed-paper-tape.html

It’s surprisingly inexpensive

MichaelG.

Maybe you're already aware of the minefield here, but be sure of the legality of this before you proceed. I reloaded high-pressure rifle rounds for decades for my own use, but I think making ammunition for transfer to others has further legal complications. Dismantling 16-bore centrefire ammunition and reassembling to a pinfire casehead would probably have similar - or worse - ramifications.

Most paper tubes are specified with an ID rather than OD because of how they are made. 0.75" or 19mm is quite smaall First thing that came to my mind was pyrotechnic tubes. looking for inch sizes brings up american sites like https://www.pyrodirect.com/paper-tubes/

Don't know how many you need but you could try talking to these people in the UK
http://www.crayford-tubes.co.uk

Sorry to state the obvious, but make sure you are legal with making these. Firearms offences carry heavy penalties. Cases are probably not a problem but the law is only clear when tested in court. There were custodial sentences handed out a couple of years ago for making ammuntion for vintage weapons. That was deliberate criminal activity (using mini-lathes) but it would not be good to get accused of the same thing.

Gentlemen, thank you all for your replies, the legal aspect will need to be clarified before proceeding any further. To own a pinfire does not require any certification as it is obsolete, but if ammunition is available the weapon then needs to be entered on to the shotgun certificate of the owner before use. I can see the potential but thanks for alerting me to the issue. Robert Butler

Reloading shot gun shells is legal. This will almost certainly involve black powder, which does require a license. The gun must be included on a shotgun certificate, too.

I’ve reloaded thousands upon thousands of home loads. One is limited to a minimum of six projectiles per cartridge (or maybe it is more than six).

Thank you NDIY, I do have a black powder license and load cartridges using new cases but perhaps as i need to make the cases puts this project into a different category and well worth checking. Robert Butler

Robert, you might try model rocket body tubes. They are a cardboard tube with a nice smooth finish. Estes is one popular brand. Their BT20 tubes are .710" ID .736" OD. E rockets has BT30 Semroc tube which is .715" ID .759" OD. Just food for thought. Hope this is of use.

16-bore all-brass centrefire cases (eg. by MagTech) are theoretically purchasable, though I dunno if anybody in UK imports them. Converting those to pinfire would at least give some assurance that the main pressure-bearing component of the ammunition is sound over most of the relevant area, since plugging the c/f flashhole and primer pocket should be reasonably straightforward and reliable.

Aside from legal issues, the thing that would worry me most is that we're talking here not about reloading commercially-made fired cases, but constructing the main pressure-bearing component without either detailed specification or the component-level test equipment a commercial maker would have.

Call me a wet hen. I've done worse things for meself, but not for anyone else to shoot.

Robert,

If you have a SC and black powder magazine licence I don't see a problem as long as you (or the owner) put the pinfire gun on a SC bfore you assemble a cartridge. Maybe to be 100% do the final loading & fitting of primer at your friends premises or let him do it. You SC will cover the parts. My comment was in case you did not have a SC.

Mick, the cartridge in any weapon is not normally load bearing, at most it provides a seal. Athin wall might jam in the breech but not cause structural failure. Common sense on material thickness should be enough.

Robert G9RPI

Robert, at the intersection of chamber end and breech face, as well as in any chamber recesses such as extractor pockets, the case is the only thing between several tons psi hot gas pressure and the shooter's face. It does provide a seal, but obturation isn't necessarily a trivial matter.

It's true that shotgun pressures are much lower than rifle, but they're applied over a larger area. Separation of tube from casehead is especially dangerous if it remains in the bore, the shooter ejects without noticing and loads another round.

Edited By Mick B1 on 08/03/2020 09:34:24

Your last point is a very valid one. I knew a fellow that removed the lead from a 12 gauge cartridge and fired it off as a ‘better’ November 5th banger. Worked well. The second attempt blew the gun apart. Attributed to a wad left in the barrel.

The fellow was lucky with only cuts and abrasions. The gun was a rather expensive loss.

Gentlemen. Oops I may have posted a blank. Shotgun cartridges are made from thin wall paper or plastic tubes and unsupported would not stand the force of the explosion, it is the chamber/barrels which contain the forces generated by detonation. Apart from trials of new loads cartridges are not routinely proof tested.

Pin fire guns are not fitted with ejectors and some have no extractors relying on the protruding pin to remove the case from the chamber. Therefore if the case detaches it will be obvious when opening the gun to reload as only the brass head will be left. Not to dismiss the detached tube as trivial and having checked the legality of the project much experimentation with adhesives and tests including submission of ammunition to the Birmingham Gun Barrel Proof House will be undertaken before using in earnest.

I had discounted tinkering with centre fire ammunition as not all pin fire guns have a chamber rim and those that do have a much slimmer and narrower rim than modern guns/cartridges. I do know of at least two conversions which involved swageing the cartridge head to accommodate the lack of or smaller rim. A brass insert with a cavity to accept a percussion cap was then fitted to the vacant primer socket.

Thank you all for your contributions and help so far. Robert Butler

Robert, An interesting project and I wish you well with your endeavours, however please keep in mind that whilst it is not illegal to load ammunition for any type of firearm -- provided you have the necessary UK certificate -- and its for your own personal use.

It is however an offence to to reload ammunition for another party, even for free, unless you are CIP Proof house approved as an ammunition manufacturer where your ammunition is tested and approved by a CIP proof house, in the UK Birmingham or London but I believe the testing is largely done at Birmingham. All ammunition sold in the UK is marked as approved on the box.

Manufacturing the components i.e. cartridge cases may be a grey area, I have no idea but would suggest you contact Birmingham proof house, you will find them very helpful I'm sure.

I would also suggest your friend ensures that his gun is still "in proof" under he rules it was tested for - many old guns are way out of proof and thus unsafe for service unless re-proved at the proof house.

John

Just a thought, if the gun is so old ammunition is not available it means the barrel is old too. Will it still be safe to fire?

I was thinking of later, when eyes and mind are focussed on the place where clay or quarry are likely to appear, and practiced hands flip out empties and reload without actually laying eyes on the piece or noticing anything out of the ordinary.

Not quite the same situation, but my old .303 SMLE occasionally produced a casehead separation with reloaded cases. Yes, I should've noticed the ejected stub casehead, but generally the first I knew of it was when the next tapered round wouldn't chamber. A separated parallel tube in a shotgun round would be more of a risk because it might not produce that jam.

That's a matter for informed inspection. I shot a .577" Snider from the 1870s for years using 'nitro for black' loads with modern propellants. If the cartridges are sound and the loads worked up sensibly with ongoing observation of outcomes, there's usually plenty of warning of developing damage before any real risk of gun failure's incurred.