"David" high-velocity anti-tank gun

[Tony Williams]

A paragraph from Ian Hogg's "British and American Artillery of World War 2":

"An interesting derivative of the 2pdr was the Canadian "David" high-velocity gun. This was designed in 1942 and was essentially a 2pdr with an enlarged chamber and a 6pdr breech firing a round which comprised a 2pdr shot and a 6pdr cartridge case. Development was slow, because of problems in ammunition design. A gun and ammunition were sent to Britain for trials, but there were still in progress when the war ended. The project was finally abandoned, but it had yielded much useful information on high-velocity guns which proved useful in other applications".

You can see photos of the ammunition here.
The cartridge case is significantly wider and longer than that of the 40mm Bofors, which itself was slightly bigger than the cartridge for the British 2 pdr tank/anti-tank gun.

Does anyone know of a source of information or photos of this gun?

[rob love]

There was a "6 pounder" sitting in front of 2PPCLI when it was in Winnipeg, When they moved to Shilo, it too came to Shilo, located in front of the HQ area of their complex. As it turned out, it was on loan from the RCA Museum.
They had a large anniversary in 2014 , and wanted to tow it behind one of three carriers at displays that summer that they were attending. The tires were well past their prime, and they asked if we could install new tires. I was not full time at the museum yet, so volunteered to bring the old tires home, remove and sandblast the rims, install new tires and re-install them. Next thing they wanted it painted up. I offered them a 20 footer (looks good from 20 feet away) so I recovered the gun and gave it a quick sandblast. It was then that I noticed the bore was closer to 40mm rather than the 57mm of a 6 pounder. Also, a 6 pounder muzzle break that I had picked up off MLU was way too large for the end of the barrel. Also, the forward barrel clamp was too large. Looking at the barrel, it almost looked hodge-podged.....something was a little off about the area where the barrel tapered.

Anyway, I queried Doug Knight here in Canada. and he pointed out that it was likely "David".

PPCLI did not want it back, and I had intended to use it for some parades and displays with the museum myself, but it was sent out to the golf course to full-fill a request by them for lawn ornaments.

I sent some photos of it to Harold Skaarup, who has some terrific pages showing all the monuments in Canada. You will find it on this page, although it will be somewhat confusing since it is shown on the page as a "David" 2pr, and just below that entry it is still shown as a 6pr.

http://silverhawkauthor.com/artiller...useum_423.html

According to Doug Knight, it had a barrel life of about 150 rounds. if I recall. He has a paragraph or two about it in one of the Service Publications booklets on the 2pr.

[Tony Williams]

Many thanks Rob, that's great information - and a great site you've linked to!

[rob love]

Looking at the thread on BOCN that you linked to, I see there still exists an original round for this gun. I am not sure that we even have a round for it.

Could you imagine trying to identify something like that in the days before the internet?

[Ed Storey]

Here is a photograph of "David" when it when it was still parked beside the parade square at CFB Winnipeg in 1997. I wonder what happened to the brass plaque that was on the gun shield?

[rob love]

No idea about the plaque.....if you look at the photos of the gun on the link I gave, there is one with a plaque of some form sitting loose on the breech ring. That photo was taken here in Shilo before I worked on the gun, so if that was the plaque you were talking about, then it appears to have found it's way loose.

[Ed Storey]

Yup that looks like it. I was hoping the plaque would be wartime with some unique information on it - oh well. Good to hear that Shilo has the gun and that it is not sitting in a scrap yard.

Any idea where the Pak 38 went that was sitting with "David" on the same parade square?

[rob love]

The PAK38 is still at 2VP.

There was a carrier there as well. The carrier had been assembled out of two, and was a bastardized mix of mk1 armour on a mk2 hull. They tried (unsuccessfully) to get it running for the anniversary that year. Later, a funding arrangement was made and it came to the museum for overhaul. I was able to get the engine running in short order, but out-door storage, a lot of wear, along with some 30 years of patchwork maintenance had really taken a toll on it. It was stripped just about to the bare hull and is now finally looking like something. It shoudl finally move under it's own power this week, once the steering box is back together and the linkages are adjusted. I think it will be one of the best carriers I have restored to date, although there are still signs on the lower that it was a mk2. Alas, that would be another thread.

[Tony Williams]

Originally Posted by rob love

Looking at the thread on BOCN that you linked to, I see there still exists an original round for this gun. I am not sure that we even have a round for it.

Could you imagine trying to identify something like that in the days before the internet?

There are some paper data files available on the dimensions of 20+mm calibre cartridge cases, the best known being one by Bob Hawkinson in the USA. Even that doesn't include this round though - too rare. So yes, I have to admit that the internet is marvellously useful to those of us with obscure hobbies!

Do your sources say anything about the muzzle velocity achieved with different weights and types of projectile?

[rob love]

I have nothing on them. I guess Doug Knight would be the guy to get a hold of. I am guessing he got his information from Archives Canada.

Not sure if we have any information in the museum's library. It's a different building than the one I work in, so I don't have much to do with that stuff.

Perhaps if somebody has Doug's booklet on the 2 pounder in Cdn service, they could relate what information is in there.

[Tony Williams]

Originally Posted by rob love

Perhaps if somebody has Doug's booklet on the 2 pounder in Cdn service, they could relate what information is in there.

I would be grateful if they could.

Can anyone help?

[Ed Storey]

$10.00Can plus postage will get anyone the book from Service Publications.

https://servicepub.com/product/the-2...nadian-service

[tankbarrell]

http://www.bookworldws.co.uk/pounder...ce-p-4094.html

Other booksellers are available! It's worth getting.

[Colin Alford]

Gents,

If you are interested in an in-depth read of war-time documents pertaining to this gun see this link:

http://heritage.canadiana.ca/view/oo...2/1613?r=0&s=1

There are 3 files pertaining to it's development and trials:

55/2100/P2 - Proj No 2 - 2 pr David H.V. Gun - starts at image 1613 (above link) and ends image 1896.

55/2100/P2/2 starts at image 1898 and ends at 2144.

55/2100/P2/3 starts at image 2149 and ends at 2294.

The documents in these files are placed in reverse chronological order so the reader may wish to start at image 1896, work backwards to 1613, skip to 2144, work backwards to 1898 etc.

Happy reading!

Colin

[rob love]

Holy smokes Colin....lots of information there.

[Colin Alford]

Gents,

The files listed in my previous post were Canadian Military Headquarters-London files.

The following link will get you to the Army Technical Design Branch files related to the "David"

http://heritage.canadiana.ca/view/oo...5/2955?r=0&s=4

These files start at image 2955 (above link) and end at 3668.

My disclaimer: I have no specific interest in this topic and merely used this evening to test my research skills.

With that said, as I was skimming through the file trying to find the end of it I noticed some information that is worth some discussion:

The attached 5 documents seem to indicate that there was some confusion regarding correct nomenclature.

They can be found at images 3472, 3482, 3443, 3423; and 3534

Here is my interpretation of the war-time documents:

There were only 4 true "David" guns produced (2 Pr H.V. on a 2 Pr Carriage with 360 degree traverse and fitted with Muzzle break): Ex 19 and Ex 20 were sent to the UK, their barrels became worn during firing trials and two new barrels were produced and shipped. Ex 81 and Ex 82 were produced at the same time as the replacement barrels and were intended to stay in Canada.

Ex 54 and Ex 55 were essentially 6 pr guns on 6 pr carriages but with 2 pr bores. These were intended to stay in Canada and be used for firing trials. Ex 55 subsequently was modified by having the barrel drilled to accept pressure gauges.

The post-war "confusion": In the typed text of the last document (Feb 46) the two guns on 6 pr carriages (Ex 54 and 55) are identified as "Davids" but this is contrary to the war-time documents. In the handwritten note at the bottom of the page (which was subsequently scratched out) it seems to say "Not Davids. Davids are 6 pr bored for 2 pr" with an arrow pointing to the information regarding Ex 81 and 82. Again this is contrary to the war-time documents

My deduction is that the Shilo gun is likely Ex 54 due to no obvious (in the available images) barrel drilling for pressure gauges.

Given this information I think that it may be incorrect to refer to the Shilo Gun as a "David" although it was certainly part of the "David" project and designed to fire "David" ammunition.

Colin

[Tony Williams]

Wow - I am most impressed, gentlemen, thank you for taking the time to help!

[Tony Williams]

Originally Posted by tankbarrell

http://www.bookworldws.co.uk/pounder...ce-p-4094.html

Other booksellers are available! It's worth getting.

Thanks, that one has arrived, along with Roger Lucy's book Secret Weapons of the Canadian Army (which has rather more info).

[rob love]

I pulled the 2 pr off the golf course a week or two back, repaired both tires and gave it a quick coat of paint before it moves over to the main museum. I thought I would put some photos on here. I could not find the EX number. The carriage number does not match the documents Colin showed and I didn't spot a breech ring number. The number may well be on the breech end of the barrel, covered by the stuck breech block, so it will remain a mystery for now. Note it has the groove and keyway for the littlejohn attachment (I believe).

I had a look earlier in the week.....as can be seen it is raining now with possibly some snow flurries today, so the details did not come out that well.

[tankbarrell]

Breech ring number is usually stamped vertically on the right hand rear face of the ring. There should be two numbers, one starting FL which is the part number and one starting B/R Lxxxxx which is the serial number.
The barrel will have its own number stamped on the rear face.

The ring is stamped as a tank ring rather than an AT gun ring.

[rob love]

OK, so I scraped away the paint in the area of the markings at the back of the breech, and here is what I found. Still no EX numbers.

[David Dunlop]

Rob. The end section of the barrel in Ed’s photo from Kapyong looks a lot longer than the one on the gun you just posted pictures of. Are they two different guns by any chance?

David

[rob love]

Same gun. If you blow the photo up you can see the groove on the end of the barrel.

[tankbarrell]

Originally Posted by rob love

OK, so I scraped away the paint in the area of the markings at the back of the breech, and here is what I found. Still no EX numbers.

With a blank serial number!

[rob love]

Originally Posted by tankbarrell

With a blank serial number!

Yep. I'm going to have to touch up the paint in that area and the mystery will have to wait for someone else to solve it someday in the future. Perhaps when the entire gun is stripped or sandblasted, the numbers will show up. In the meantime, I'll copy and insert some of the relevant information into the gun's electronic file.

[rob love]

I went back to my old emails that I had with Doug Knight on this gun from when I first (re) discovered it. His opinion was :

This is the 2-pounder “David” high velocity experimental gun. Somebody must have plunked it on a standard 6-pounder carriage.........

He finished the email with:

The muzzle brake is missing - interesting in that I have never seen the end of the barrel inside the brake - didn’t know it had a keyway.

So, in Doug's learned opinion, this was one of the Davids, but now installed in a 6pdr carriage. Trials went on through to at least 1945, so possibly, when the 2 pounder system with 360 traverse was abandoned, they moved it to a more conventional carriage to continue to perform tests on that style ammunition. I'm not so sure this was gun no. EX54, in that the material Colin found talks about it being a 6 pdr barrel bored to only 40mm. This is not a 6pdr barrel.

Hopefully one day the gun will get a proper paintjob, at which time the EX number may come up.