What's new
British Ordnance Collectors Network

This is a sample guest message. Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

32 pounder, 3.7" and the 28 pounder guns and shells

Vollketten

Member
I am looking for information on the British 32 pounder antitank gun and I admit to being a little confused.
yPEMJXF.jpg
Jedsite (http://www.jedsite.info/artillery-0/0-pdr/32-pdr_series/32pdr-series.html) says:

"The gun was originally designed as a 37lb anti-tank gun (basically the 3.7in AA gun on an anti-tank mounting but tests proved it was a failure and that a 32lb version was more effective. Two carriages were built with different recoil systems but the war ended before production could begin. It was apparently an impractical ATG as it would have weighed 10 tons and manhandling it in and out of concealed positions was totally impracticable. Trials continued through 1946, including tests with infrared night sight. After the Army had finished with them one went to the Royal Artillery Museum and the other was scrapped."

It goes on to list variants as:
37 pounder (Prototype)
32 pounder (First Prototype)
32 Pounder (Second Prototype)
and mention of the Tortoise tank

I have been in touch with The Royal Artillery Museum at Woolwich and after I'd sent an email there yesterday the librarian there confirms they have no data at all on the gun or examples of ammunition for it. Just the gun itself.
RGc1zUO.jpg
RAM Example

So the information I am after (pretty much anything at the moment) but specifically:

In January 1941 I have an original reference stating that a "preliminary outline drawing for OQF 3.7 Monobloc in 17 pounder breech end and carried in 17 pounder Tank Mountings, which carried balance springs but has S.A. gear removed was put forward for development and barrels were ordered and tested
----------So could someone explain how that would work for me please?

It does also say later on that the 17 pounder sights were being recalibrated for the 3.7" to allow it to accurately fire 3.7" AP and APHE shells
---------- Is there someone who has some of these rounds?

The document goes on to say that a "higher efficiency brake" was being developed [for this gun] if required and that although the "medium efficiency normal type of double baffle brake" should be adequate that this higher efficiency type would be manufactured and available if required.
---------- Yet I have only seen the muzzle brake on the Tortoise (32 pndr) and not one at all on a 3.7"
---------- Could someone help with what the muzzle brakes in question would actually be here?*

The final part of the document is a proposal of armour penetration performance comparing what it calls a "3.7" holding up to 28lb" at 2670fps compared to a 17pdnr at 3000fps and despite what it says on wiki the estimates are that the 3.7" is superior against armour at ranges over 1500 yards and in other ranges a better artillery weapon because of the HE round

If someone could help me to untangle and make a bit more sense of this I would really appreciate it. Especially if they happen to have a handbook or some other documentation.

*So on the issue of the muzzle brake:
Would it be a fair assumption that this double baffle 'standard type'?
KaWFKz9.jpg
and that this muzzle brake on the 32 pounder on the Tortoise is really as much of a counterweight than it is some high efficiency brake?
vqkB0ka.jpg
which leaves the question of what the 'higher efficiency type' brake for the gun could be in 1941.
Conveniently 1941 is also the year that the Galliot type brake was tested in the UK and The Defence Academy at Shrivenham still has the 32 pounder Galliot brake which apparently was tested on a Mosquito aircraft.
hZS82cb.jpg

Any help, thoughts or ideas and especially any ammunition related data would be much appreciated. In the mean time I'll keep looking at Kew for more.
 
have you contacted Shrivenham? think the correct title is' The Royal College of Military Science' at Shrivenham Wiltshire.
 
The bottom photo was sourced from a friend who visited there and they confirmed that some trials had been carried out of a Galliott fitted to the 32 pounder and to the 17 pounder guns. there are even photos of it on the 17 pounder.
Kew has some documents relating to both which I'll be requesting at some point.
 
Pic taken several weeks ago of 32 pdr !


Rob.................rnixartillery.
 

Attachments

  • DSCF2980.jpg
    DSCF2980.jpg
    278.4 KB · Views: 68
  • DSCF2981.jpg
    DSCF2981.jpg
    287.6 KB · Views: 64
37MuzzleBrake5.jpg32MuzzleBrake1.jpg32MuzzleBrake2.jpg32MuzzleBrake3.jpg32MuzzleBrake4.jpg

I apologise for the state of the images above, which are scans of seriously poor microfilms. They may be of passing interest.
 
Thanks guys that great.
Have a trip to Kew in the next few weeks with a hunt for me and the testing of the Galliot brake on some guns as well as some other stuff.
 
Some data on QF 32 pdr:
3,7" calibre, barrel of 62 calibres, chamber volume 550 cu in, working pressure 22 tsi.
Mv of 32 lb APCBC shot - 3100 fps.
In 1946 various experimental APDS were tested. Cores were designed as scaled up 6 and 17 pdr cores, 1,86 in diameter, 7 1/2 lb weight. APDS with "service" sabot (in lines of 17 pdr APDS) achieved mv of 4750 fps with chamber pressure of 21 tsi. Second design was pot-petal hybrid sabot (Permutter design with retaining petals, not Caddy`s Canadian pot sabot). The third and the last one was "petal" sabot, looking like "service" with shear points moved to forward of sabot (just like it was later introduced for 105 and 120 mm APDS). Thas specie achieved mv of 5050 fps (22 tsi chamber pressure).

During plate trials experimental APDS (of not specified type) holed 200 mm thick plate at angle of attack of 40, 45 and 50 degrees (obliquity; 50 degrees obliquity would be plate at 40 degrees NATO, in this case - 311 mm line of sight) and striking velocities up to 4885 fps. Also the Proof Shots were made, with Duralumin body and flat steel head screwed into it.
 
Some data on QF 32 pdr:
3,7" calibre, barrel of 62 calibres, chamber volume 550 cu in, working pressure 22 tsi.
Mv of 32 lb APCBC shot - 3100 fps.
In 1946 various experimental APDS were tested. Cores were designed as scaled up 6 and 17 pdr cores, 1,86 in diameter, 7 1/2 lb weight. APDS with "service" sabot (in lines of 17 pdr APDS) achieved mv of 4750 fps with chamber pressure of 21 tsi. Second design was pot-petal hybrid sabot (Permutter design with retaining petals, not Caddy`s Canadian pot sabot). The third and the last one was "petal" sabot, looking like "service" with shear points moved to forward of sabot (just like it was later introduced for 105 and 120 mm APDS). Thas specie achieved mv of 5050 fps (22 tsi chamber pressure).

During plate trials experimental APDS (of not specified type) holed 200 mm thick plate at angle of attack of 40, 45 and 50 degrees (obliquity; 50 degrees obliquity would be plate at 40 degrees NATO, in this case - 311 mm line of sight) and striking velocities up to 4885 fps. Also the Proof Shots were made, with Duralumin body and flat steel head screwed into it.

Can I ask what the source of that is?
 
Top