3.7" aa

[David Dunlop]

A few questions.

Does anyone know if any of these guns are still alive and well in Canada in museums or private collections?

Were any ever manufactured in Canada during the war?

At least one 3.7" SP on a Ram chassis was built in Canada during the war and tested in England. Would anyone know where in England this testing would have taken place and the possible fate of that particular vehicle?

[Tony Smith]

See This thread for more info and pics on the 3.7" AA.

[David Dunlop]

Interesting thread, Thanks.

After reading it and some other items on the internet, it seems the 3.7" worked it's way into an effective anti-tank roll as WW2 progressed and the allies gained air superiority. Several articles indicated quite significant quantities of AP and SAP 3.7" ammunition were produced and the one photo from Valcartier looks very much like the loader is holding a sabot AP round. The 3.7" was undoubtedly a brute to move around, particularly the later marks built on the sleeved down naval 4.5" gun. The tapered rifle grooves and addition of the shoulder guide band on the shell apparently gave the later mark 3.7 incredible accuracy as a ground support and anti tank gun and at an effective range far better than the 6, 17 and 25 pounders were capable of achieving. Must have been a real eye opener for the first German tank crews to encounter one!

[REL]

Originally Posted by David Dunlop

Interesting thread, Thanks.

After reading it and some other items on the internet, it seems the 3.7" worked it's way into an effective anti-tank roll as WW2 progressed and the allies gained air superiority. Several articles indicated quite significant quantities of AP and SAP 3.7" ammunition were produced and the one photo from Valcartier looks very much like the loader is holding a sabot AP round. The 3.7" was undoubtedly a brute to move around, particularly the later marks built on the sleeved down naval 4.5" gun. The tapered rifle grooves and addition of the shoulder guide band on the shell apparently gave the later mark 3.7 incredible accuracy as a ground support and anti tank gun and at an effective range far better than the 6, 17 and 25 pounders were capable of achieving. Must have been a real eye opener for the first German tank crews to encounter one!

There's very little evidence of them being used in the anti-tank role, though from the photos in the other thread, they were used as field artillery more often by 1944/45. Presumably because the 17pdr. was available by then for anti-tank work, and perhaps because the change from AA fire to indirect fire probably did not require the gun to be brought into the forward combat area to extent that AT work would have. Still from what I've read of the campaigns in 1944-45 there was no surplus of AT guns on the Allied side, and 3.7s would have done a nice job against the Tigers at very long ranges.

Just another lost opportunity due to hide-bound thinking and negligence.

They do seem to have been remarkably accurate, like the German Flak 36.

More info here: http://www.mapleleafup.org/forums/sh...t=12815&page=2

[David Dunlop]

My father-in-law had trained at Shilo MB for Pacific Force, but when the war ended, instead of being De-mobbed, they upped his points requirement and sent him to RCAF Station MacDonald, which by then had been turned into a War Assets Storage and Disposal site. Train loads of equipment arrived every week and they used FWD Tractors to haul items from the nearby rail siding to the base. He commented it all seemed to arrive in organized batches and for a while it was nothing but light and heavy artillery. Boxed Polsten, Orlikon and Bofors guns had to be stored in the hangers, but the trailer ready units were all lined up outside. There were quite a lot of 40mm Bofors, 17 and 25 pounders and dozens of 3.7" AA pieces. Quite a bit of the smaller stuff was later returned to longterm military storage somewhere else in Canada, but every one of the 3.7" guns were sold to a Selkirk, Manitoba Steel Mill for scrap and they always went with a military escort to the mill to ensure they were properly disposed of on site. Though he did admit that by the end, the escort typically went off for lunch etc. in Selkirk and left the mill to their own tasks. A lot of Mk ! Carriers ended up there days at the mill as well.

[Doug Knight]

David

I am not sure if any are in Museums in Canada - there is none at the Canadian War Museum, but there may be one in Shilo, Manitoba.

We produced the 3.7-inch gun in Canada and by the end of the war, 1,740 C Mk 2 and 1,739 C Mk 3 mountings, and 5,129 loose barrels had been delivered, as well as about 6 million rds of ammo.

The 3.7 on the Ram was tested in January 1943 at Lydstep in the U.K, and the results were completely unsatisfactory. The test officer was Captain, later Lt-Col Willis Roberts, who is still alive in Fredericton NB. The gun and the tank were disassembled and returned to their normal function.

The story of the 3.7-inch AA gun in Canadian Service is the subject of an upcoming publication in the Service Publications Weapons of War series - probably early next year.
Hope I have wheeted your interest.

Regards

Doug

[sapper740]

Originally Posted by David Dunlop

A few questions.

Does anyone know if any of these guns are still alive and well in Canada in museums or private collections?

Were any ever manufactured in Canada during the war?

At least one 3.7" SP on a Ram chassis was built in Canada during the war and tested in England. Would anyone know where in England this testing would have taken place and the possible fate of that particular vehicle?

There's one in Canadian Forces Base Borden, right before the McDonalds. My humble apologies if this has been previously mentioned, I didn't have time to read all the archived posts.

[rnixartillery]

Hi Guys,

Just took delivery of my latest addition to the collection,A Genelco Canada made 3.7.
Requires a complete restoration but have no time at the moment so it will take its turn,This is one of the ex-portugees guns that came back to the UK in the late 1980's.
Pics attached.


Rob.......................rnixartillery.

[John McGillivray]

With respect to performance, the British 3.7in gun appears to be closer to the German 105mm Flak 38 gun than the 88mm Flak 36

3.7in Mk.II L / 50
Weight – travel- 9401kg (20725lbs)
Weight – firing- 9326kg (20541lbs)
Weight of HE shell – 12.96kg (28.56 lbs)
Muzzle Velocity- 793m/s (2600ft/s)
Maximum range (horizontal) - 18800m (20660yards)
Maximum range (vertical) - 12000m (39370ft)
Effective ceiling – 9760m (32000ft)
Penetration Data: AP Mk II
Weight 12.6 kg – MV 793m/s (range – penetration RHA/FHA @30deg)
100m – 131/116mm, 500m – 124/110mm, 1000m – 116/103mm, 1500m – 108/96mm, 2000m – 100/89mm.


105mm Flak 38
Weight – travel- 12700kg (28000lbs)
Weight – firing- 10224kg (22533lbs)
Weight of HE shell – 14.8kg (32.6lbs)
Muzzle Velocity- 881m/s (2890ft/s)
Maximum range (horizontal) -17380m (191000yards)
Maximum range (vertical) - 11400m (37401ft)
Effective ceiling – 9450m (31000ft)
No penetration data

88mm Flak 36
Weight – travel- ?kg (?lbs)
Weight – firing- 4983kg (10983lbs)
Weight of HE shell – 9.4kg ( 20.7lbs)
Muzzle Velocity- 820m/s (2690ft/s)
Maximum range (horizontal) - 14815m (16270yards)
Maximum range (vertical) - 9900m (32480ft)
Effective ceiling – 8000m (26246ft)
Penetration Data: PzGr. ( Armour Piercing Capped Ballistic Cap)
Weight 9.65kg – MV 810m/s (range – penetration RHA @30deg)
100m – 97mm, 500m – 93mm, 1000m – 87mm, 1500m – 80mm, 2000m – 72mm.

[chrisgrove]

Post war in UK, the 3.7 inch ordnance was used for the 32 pounder towed AT gun (and for the Tortoise). AT defence was by then an infantry task and any infantryman seeing the 32 pounder would immediately recognise that the thing was just too big to be concealed in an infantry position. Thus the successor to the 17 pounder was the recoilless 120mm BAT (and its descendents MOBAT, CONBAT and WOMBAT).

The Firepower museum in Woolwich UK has a 32 pounder, though I cannot recollect seeing it since they moved from the Rotunda.

Chris

[rnixartillery]

The 32 pdr gun was on the disposal list when Rotunda closed so 'who knows' were it has ended up !

Rob.....................rnixartillery.

[Tony Williams]

Originally Posted by chrisgrove

Post war in UK, the 3.7 inch ordnance was used for the 32 pounder towed AT gun (and for the Tortoise).

Not quite. The ammo for the 3.7" AA and 32 pdr was different, so needed a different barrel to fit.

And of course there were two very different types of 3.7" AA - the Mk 6 was much bigger than the Mks 1-3 guns and used larger cartridge cases for a much higher velocity.

So there were three cartridges used in the same calibre, none of them interchangeable:

3.7" AA Mks 1-3: 94 x 675R with 135mm rim diameter (12.7 kg shell fired at 790 m/s)

3.7" AA Mk 6: 94 x 857R, rim 150mm (12.7 kg shell fired at 1,040 m/s)

32 pdr AT: 94 x 909R, rim 141mm (14.5 kg shot fired at 878 m/s).

See: http://quarryhs.co.uk/ammotable10.html