3.7in AP Shot

[J.McGillivray]

Here are some photos of a 3.7in gun being test fired on the ranges in Valcartier Quebec in Feb. 1943. The round being loaded into the gun appears to be painted black indicating that it is AP shot. This appears to be a setup to measure muzzle velocity. Note that the 3.7in AA Gun has a much lower profile when in a horizontal firing position, then the German 8.8cm Flak guns

[JimWeb]

Zooming in on the 'loading' image reveals a projectile with a flat nose - its more than likely a proof round used to test the gun after manufacture.

[A2_Prius]

Was the 3.7 in. ever employed in the AT role fulfilled by the 8.8 cm.? By '43 the Allies were well acquainted with the latter's "dual role" capability, and it seems to me that the 3.7 in. gun probably had the same potential.

[bsmart]

No I've read it was specifically not fitted with ground sites when issued to units so that it could not be diverted from it's primary role as an AA gun.

Especially in the desert the role of protecting the base area around the Suez Canal was considered too critical to allow it to be diverted. Between use there and in UK based AA units production could barely keep up with demand

I assume the 17pdr was considered adequate. I also read recently that the 32pdr At gun that was being developed at the end of the war was based on the 3.7" but the towed version of that gun was a monster to move around. I think in the 32 pdr form it was used in the Tortoise (The British vehicle similar to the T28)

[J.McGillivray]

According to the regimental history of the 2nd Cdn HAA Regt. their 3.7in AA guns were fitted with sights to engage ground targets both by direct and indirect fire. Besides the AA role their training also involved anti-tank drills and artillery shoots.

Looking at the photo closer it dose look like the round is a Flathead. Since these are also solid shot they would be painted black like the AP Shot.



Below are diagrams of the three main types of ammo for the 3.7in AA Guns. First the 3.7in AP Shot Mk 3T, the 3.7in HE Shell and the 3.7in Shrapnel shell.

[JimWeb]

- A2_Prius

Was the 3.7 in. ever employed in the AT role fulfilled by the 8.8 cm.? By '43 the Allies were well acquainted with the latter's "dual role" capability, and it seems to me that the 3.7 in. gun probably had the same potential.

Several books mention that they were used against tanks during the fall of Tobruk - the regiment responsible for the air defence of the harbour held off rommels panzers for several hours until they ran out of ammunition. The ammunition in question was unfuzed HE (normal HE round with transit plug fitted in place of fuze) apparently...

The unit in question IIRC was 68 HAA Regt RA and I think the Peter Cochrane book mentions it.

[J.McGillivray]

- bsmart

No I've read it was specifically not fitted with ground sites when issued to units so that it could not be diverted from it's primary role as an AA gun.

Especially in the desert the role of protecting the base area around the Suez Canal was considered too critical to allow it to be diverted. Between use there and in UK based AA units production could barely keep up with demand.

There were different models of the 3.7in AA gun going up to the Mark 6. There were both static and mobile types. It sounds like the guns sighted along the Suez Canal may have been static types. The 2Cdn.HAA Regimental states that “…in Africa; the gunners with the 8th Army had also on occasion used their 3.7 guns against enemy columns and concentrations.�

In NWE the 3.7in AA guns were most often used in the field artillery role, especially for counter battery and counter mortar shoots. I have heard one report that the British had used their 3.7in AA guns to snipe at German tanks across the Rhine River in 1945.

Note that 3.7in AA guns were also manufactured in Canada and Australia during the war.

[David_Clark]

Field Marshall Sir Alan Brooke's memoirs include several mentions of visits to demonstrations of 3.7" guns in the anti-tank role. If I remember correctly, the demonstrations mainly took place prior to the introduction of the 17pdr.

Perhaps while the anti-tank potential of the 3.7" gun was evident, the introduction of the 17pdr eliminated the operational requirement for the 3.7" gun to be used against ground targets.

David

[JimWeb]

The introduction of the proximity fuze also made them effect against dug-in infantry and they were used in this role in NWE and Burma.

[Roger_Lucy]

[quote="J.McGillivray"]Here are some photos of a 3.7in gun being test fired on the ranges in Valcartier Quebec in Feb. 1943. The round being loaded into the gun appears to be painted black indicating that it is AP shot. This appears to be a setup to measure muzzle velocity. Note that the 3.7in AA Gun has a much lower profile when in a horizontal firing position, then the German 8.8cm Flak guns

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In July 1942 the Canadian Army Technical Development Board commisioned a one-off 3.7 inch SP on a Ram chassis. The gun used was a Mk.II 3.7-inch anti-aircraft gun, on a Mk.III mounting (less its wheels, predictor and other parts below the roller race) made by General Electric in Peterborough Ont. Aside from the standard AA sights it had both a No.9 dial sight for indirect fire and a modified No.33 anti-tank sight.
In trials in the UK the Ram 3.7 inch SP was not terribly effective in either an AA or in-direct fire role, but tests carried out on 23 March, 1943 at the Combined Operations School in Poole, showed it performed very well in a direct fire role.

Paper studies were then carried out to look at the feasibility of mounting either a 17-pounder or a 3.7 inch AA gun on the Ram Sexton chassis. The 3.7 inch was deemed to offer marginally (5mm) superior armour penetration out to 1,000 yards, and significantly better beyond that range. A paper study was also done for a 3.7 inch as an assault gun mounted on an M4 chassis, for use against beach fortifications. Neither of these studies got beyond the drawing board but do show that the 3.7 inch AA gun was seen as potentially ahighly effective direct fire weapon.
For more details on these projects see my "Secret Weapons of the Canadian Army" Service Publications 2006.

[JimWeb]

[quote="Roger_Lucy"]

- J.McGillivray

For more details on these projects see my "Secret Weapons of the Canadian Army" Service Publications 2006.

I'm waiting for the film version

[Roger_Lucy]

I'm waiting for the film version ;-)

8)[/quote]
I wish! There are lots of references to films being taken of various equipment trials, but all that seems to have survived are a few stills- such as this one of the Ram 3.7 inch SP wading ashore during the 23 March 1943 trials at Poole.

[J.McGillivray]

In this article in US Field Artillery Magazine from Jan. 1943 there are references to the British 3.7in AA gun being used in the anti-tank role like the German 8.8cm Flak gun.
sill-www.army.mil/FAMA..._25_27.pdf
Source
sill-www.army.mil/FAMA...chives.htm

[warddw]

I have a nice example of the 3.7" AP Ammunition in my collection...let me know if you want a picture posted...

[J.McGillivray]

It would be nice to see a photo of the 3.7in AP shot.