Dischargers, smoke generator, 4 inch
 

I happened across this manual while putting away duplicate books for in the library here in the RCA Museum. It answered a few questions about the 4 inch dischargers, such as how far the smoke cannister was projected (A: aprox 125 yards). I don't have access to the room with the scanner right now, and as well the book is pretty new so I don't want to fold the pages over, so you'll have to be happy with photographs.

The manual also covers various 2 inch dischargers as noted on the index page, however I have not copied those pages. If someone really wants to see them, let me know and when I get time I can photograph those as well.

Last two pages. Last page covers the ammunition. The last photo is from the internet and shows the crate which would include 10 smoke rounds, 12 covers for the muzzle (they were expendable: the QM did not expect you to reach out under fire and remove it) as well as 14 ballistite .303 cartridges to launch them.

Some good links on the ammunition: http://www.bocn.co.uk/vbforum/thread...generator-no-8

http://www.lexpev.nl/grenades/europe...rsmokeno8.html

very interesting, thanks for posting it up

smoke discharger
 

robe, do you know, if these smoke discharger canisters are available anywhere, inert ones of course.

Kevin.

Had a look online and they seem pretty rare. I'm thinking a guy may end up painting some soup cans olive green and put the stenciling on them. I saw one on ebay back when ebay sold that kind of stuff, and it did not go cheap.

There is a guy on Canadiangunnutz has a pair of No24 Mk2 Smoke Generator canisters and somehow feels they are worth $1500 for the pair.

Rob,

I also thank you very much for posting on this most perplexing subject.

We have essentialy the same with our AFV's today.

Smoke grenade dischargers with disposable covers on the LAV's are an example..

Explains what and how the 4'' 's were used on our Carriers.

Very generous of your time . Thanks

In the New Year I will see if I can get a better scan of the pages.

There are a couple reports available (for a fee) from the UK archives regarding the no8 smoke rounds. They are located at the following two links:

http://discovery.nationalarchives.go...ls/r/C11244187

http://discovery.nationalarchives.go...ls/r/C11344446

Robert:
It is these odd types of threads that re-enforce the importance of the MLU. Ten years ago many of us had the same questions re the carriers, and one by one the mysteries have disappeared. It's really a team effort.

My Brother in law runs his own small car repair business and I wondered about asking him to save all the old screw on oil filters till I found one the right size for painting up as a dummy to stick out the end of my discharger :smoker:

Ron

Dimensions from 4" smoke ammunition
 

Hereby two photo's and a sketch with the main dimensions from the 4" smoke canister.
Hope this helps.

Marco

hi, that's great thanks for the info. cheers.

kevin.

The bad news for anyone in the UK is that that particular smoke discharger will come under Section 5 of the act, because it's short enough to be classed as a pistol. (So if you want one, or want a gunsmith to make you one out of No.1 Rifle parts, it will have to be deactivated and welded into a single lump.)

This is probably just as well, since if it can launch a can of soup 125 yards it's not something you want to stand in front of.

The canisters themselves are probably s5 as well, since the wartime ones were most likely white phosphorus filled (even the later HC ones would be fairly nasty in a confined space - powdered zinc and hexachloroethane, I think (has to be manufactured in very dry conditions as it can be initiated by water)).

Chris.

In the USA it is classed as a short barrel rifle (SBR per ATF) so also a device that has to be registered but still very legal to own. The smoke generator could probably be fabricated from an automobile oil filter, just a matter of finding one of comparable dimensions. Could probably hog out the internal paper filter and replace with smoke composition and some cannon fuze into the center with a black powder booster that would light from the blast of a grenade launching blank.

Attached image was downloaded from another thread a long time ago but figure it should be part of this discussion to consolidate information.

"hexachloroethane" Chris, is this the stuff in my tooth paste? :eek:
Do I need a different brand? :(

A few years ago I wrote the Enfield Arsenal in England asking about these dischargers and canisters and eventually got quite a package of material back from them including machinists drawings for both the Ross Rifle and Enfield based versions. I believe the package also included detail drawings for the canisters. Should still be in a filing cabinet downstairs somewhere. The centre base of the canisters had a very simple detonator fitted which was basically two thin metal discs with a sandwich of something like mercury fulminate in the middle. The pressure blast of the firing cartridge was sufficient to set the detonator off, thereby igniting the propellant charge. Probably not an item you would want to drop.

David

Yes, and no. :D

It's commonly used as a disinfectant/antibacterial ingredient and is perfectly OK in that application (very low concentration).

It's very nasty in screening smoke (HC) because the reaction products are lots of zinc chloride (corrosive), with some hydrochloric acid (ditto), and also carbon monoxide and phosgene (carbonyl chloride (COCl2)) mixed in.

Still much better than phosphorus smokes, though.

Chris.

As David Gordon says, we can have a live, fireable discharger here.

I have plans afoot to make an actual smoke canister that meets local reenactment safety guidelines.

Essentially, smoke compound as used for paintball games filling a cardboard cylinder, all made with no metal parts and weighing no more than one pound.

A blank .303 to ignite it and throw it down range a bit. Not an accurate tactical recreation in distance and duration, but usable for reenacting displays.

Intend to mount them on the Humber Mk4 Armoured car.

Thanks Marco. I'll give the dimensions to my brother in law to save him saving all those wrong size oil filters. Ron

Launching rounds are NOT blanks?????
The proper cartridge had a charge of BALLISTITE
A blank charge is a much faster powder and will result in major damage if attempting to launch a canister.
Blanks are manufactured for sound and effect with no barrel restrictions unless used in a semi auto. Restrictors were used for some arms however as a shredder in the case of a wooden bullet blank.

To add to that, The ballistite 303 has a flat end. (finished with a purple sealer)
The blank is crimped (like a shot gun cartridge) to a blunt point. At least that is what I have seen.

Blanks had many forms, but you are correct in that most launching rounds did have a rolled crimp and wad.
Some blanks had a roll crimp and wad, short crimp, full bullet length crimp and of course the wooden bullet blank.
Many of the "blanks" around and especially if WW I dated are mortar igniter rounds and do look like blanks but are for use in large mortars and some naval guns.

Hi David I would dearly love to get a copy of the plans that you got from Enfield Arsenal I was wandering if you could photo copy them I will shoot you some cash. I an just working on my carrier an would like to have a discharger, I do have the cup and I did manufacture a number 1 action on to it but I don't know if it is correct. Your plans would help me out deciding on how long the barrel how thick etc.

Larry

Hello David,

A friend of mine, who is a class 5 arms dealer in the UK, made a batch of these smoke dischargers copying my example lying at the front in the first photo. Is my example matching the machinist drawings you have?

Attachment 78776 Attachment 78777

There may still be a couple left for sale but not sure. It would be for UK buyers only and they come with deact certificate. Anyone interested drop me a PM and I will get you his contact details.

Cheers,

Here is a drawing made by my friend John when he made mine from a cut down deac SMLE and an original discharger tube. He took the measurements from an original at Bovington. Ron

PS. PM me with your email address if you want a copy.

Hmmm....

Have a word with your local pyrotechnics/firework manufacturer, since the obvious choice is a 4" cylindrical shell, suitably modified (no lifting charge bag/cone and a very short delay fuse - mainly to prevent the launch charge from blowing straight through and dismantling the shell before it leaves the tube) and loaded with your smoke composition and (obviously) no bursting charge - vents needed to let the smoke out, of course! Launch with a blank cartridge loaded with coarse grained black powder - one of the "cannon" grades ought to do it, because you don't want high velocity. (Nor anyone downrange of it!) And BE CAREFUL! :eek:

It would be completely illegal to produce these in the UK (unless you hold a manufacturing licence, etc.), so don't even think about it. (See the various bits of legislation (Explosives Act(s), Control Of Explosives Regulations, HSE rules, etc.) The quantity required would be commercially uneconomical, including having them made in China, (without considering the UK testing required (at your expense) before they would be allowed into the country).

Pyrotechnic manufacture being a permitted hobby/small business in parts of the USA means that you could probably get something suitable produced in small batches.

Careful testing is essential: some smoke compositions do not play nicely if firmly initiated (or overly contained - even a heap may suffice) and can explode(1). Especially test what happens if the delay element is omitted and the lifting charge blows straight through into the smoke composition!(2)

Chris. (4)
(1) Umpteen(3) years ago we discovered what would happen if theatrical smoke powder was used in excessive quantities (or added to flash powder) - you get more bang than you bargained for and very little smoke.
(2) I recall a 75mm cylinder maroon that went off in the tube, entirely too close to where I was standing, due to the "lift" blowing through or a faulty delay element. :eek: I Do Not Want To Experience That Again! :giveup
(3) Back in 1984, I think... or possibly 1982.
(4) BPA Level 2, which means I get to do the risk assessments for our displays.

Great info! All cautions to investigate with our project.

So far..... over here, a smoke pot with no illumination, or noise-bangs is not illegal to have. No license required or storage requirements for home hobbiest quantities.

The licensed part would be getting the BATF tax stamp for a Short Barreled Rifle (SBR) before cutting a shooting SMLE down to the right measurements. We have that sorted.

It may be that a manufactured .303 blank may not have the right charge....pressure, duration, lift... so we may find in testing that we need to hand load some discharger-only blanks.

Obviously, starting with the weakest charge and working up. And with blast shielding and other safety gear on and available during the testing.

It is common here to use No1 SMLEs with the clamp on grenade cup to fire tennis balls using a common blank. Usually blows a hole in the bottom, but not through the ball, so it goes downrange about 150 meters.

While "farby" the yellow balls allow us to police the field for trash after a tactical. We just have to "honor" the strike and either take the hit, or let the umpires note the effect on troops/vehicles. Yes, play acting, but a 100 man tactical event with no logistics trail is not really realistic for a war. But not too bad for a taste of the experiance and keeping safety foremost.

Just wondering if the bracket to mount the smoke discharger to hull is cast, it kinda looks like it on photos. Has any one reproduced these or have an original that they might want to get rid of.
Larry

Yes, the hull bracket on the MK-I* is cast. Bronze. Hence few and far between of the originals exist. Ben H. had copies made circa 2012/2013, in woodpecker lip cast steel. The MK-I* bracket is not interchangeable with the MK-II*.

(I am reliably advised by a good friend that original examples of UC MK-I and UC MK-I* smoke discharger hull mounting brackets can be found in steel) Kia ora L.E.

While the Quebec made Ross M-10 .303BRIT action was used for Canadian Universal Carriers, the MK-I* was remotely fired by attached cable, while the MK-II* was a conventional 'finger on trigger' release.


http://mapleleafup.net/forums/showpo...69&postcount=1

What is the diff. between the two?

This is how you will normally find the cartridges for the launcher.
http://img.photobucket.com/albums/v7...ps8xxgvntf.jpg