15mm BESA and other autocannons

[Kiwikkiwik]

Hello I found some relevant information about the 15mm BESA autocannon, wpn 101, UK OOB.
Looking at
https://sites.google.com/site/britmilammo/15mm-besa
We can see that the 15mm BESA has no HE shell.
So probably the 5 vehicles that carry this weapon should have their HE ammunition removed.

The Humber carries 150 shells, see stowage diagrams at
http://www.warwheels.net/images/Humb...eDraw1-100.pdf
David Fletcher British light tanks 1927-45 gives the 15mm BESA mounted in the Mk VIc tank 175 rounds.
David also says this.
"in practice the the whiplash action of the 15mm limited it to firing single shots.".
Also from
https://en.wikipedia.org/wiki/Besa_machine_gun
For the 15mm BESA

"It could be fired in semi-automatic mode as well as fully automatic. It was introduced in British service in June 1940 and was used on the Light Tank Mk VIC and on armoured cars such as the Humber Armoured Car Marks I–III. ... the weapon was usually used for single shots as it was difficult to fire accurately in automatic."

Notice this site gives a service introduction date of June 1940 game has March 39. March 39 is very close to the date production of the MkIVc began.

The armoured cars get 40 bursts. So using the 150 shell loadout they are firing 3.75 bullets per burst.
For the light tank with 67 bursts it is firing 2.6 bullets per burst.

For comparison the Russian T-60s (wpn 008) autocannon and the German 20mm autocannon (wpn 008) both fire 5 shells per burst.

From the excellent site
https://www.tankarchives.ca/2019/05/...netration.html
we get in reference to the autocannon mounted in the T-60,
"The precision of the ShVAK gun at ranges of up to 1000 m in bursts of 2-3 shots is satisfactory" ie any more then 3 shots/burst is a waste same would apply to the German 20mm autocannon.

The T-60 gets 156 five shell bursts, if it was firing 3 round bursts it would have 260 bursts. Applying the same burst rate of 3 to the PzKw II A/B/C changes its ammo loadout from 16 HE, 20 AP to 24 HE, 36 AP. But same as the 15mm BESA it is very likely this vehicle fired single shots which would give it 90 HE and 90 AP. Or possibly 30 HE bursts and 90 AP. In game it runs out of ammunition very quickly because of the 5 round bursts. As I mentioned earlier there is only footage of PzKw II firing single shots, not bursts.
Here is the relevant quote I supplied earlier from Terry Ganders book Military vehicles in detail 8x8 armoured cars, talking about the change from kwk 30 and kwk 38; 'The increased rate of fire made a considerable difference to the effectiveness of the anti-aircraft weapons but made no practical difference to the Gunners on the sPzSpWg SdKfz 231 (8-rad)... as they usually fired the cannon on single shot only, to improve accuracy'

T60 carries 780 shells in 58-60 shell magazines.

[Mobhack]

HE also covers ball ammo - unless you want all riflemen to have zero HE for thier weapons?

[DRG]

As Andy says the "HE" line covers standard NON AP ammo just as every infantry section in the game has "HE" ammo for their rifles

[Kiwikkiwik]

Personally I thought a comparison of the 15mm BESA to another similar calibre vehicle mounted autocannon would be more relevant that to infantry rifles. For example
The Finnish Landsverk 182 20mm actually has a HE shell but gets no HE loadout.

But and as far as rifle calibre bullets go you have the German PzKw I C firing rifle size bullets but no HE allocation. And most AT rifles fire rifle sized bullets but no HE. The 20mm AT rifles mostly have a HE shell but no HE.
On balance it could be said that the previous designers had decided that a weapon with a decent AP performance will use its bullets against armoured targets rather than "wasting" them against soft targets. You could make the same argument for the 15mm BESA, especially considering that the vehicles with it had a perfectly serviceable, much more effective, coaxial MG, the precise job of which was to engage enemy infantry. It could be considered unlikely they would "waste" the 15mm on soft targets, maybe they considered it tactically smart to conserve the 15mm for armoured targets which obviously presented a much greater threat to the vehicle than infantry. Considering this it seems to me that the games 15mm BESAs HE allocation is the exception rather than the rule.

[Charles M]

This might not be the appropriate location to post this, but the Mark VIc light tank fitted with the 15mm BESA only saw service in France 1940, although one exmple together with a sample of the wretched Covenanter were shipped to North Africa. Can some kind person please put a note in the specs for British vehicle wpn 101? Regards Charles

[DRG]

Wartime operations proved disastrous against equally fast and much better armed tanks like the Panzer II and Panzer 38(t) and, of around 400, only 6 made it out of France. This left mainland territory devoid of any sort of armour when the battle of Britain began. However, they showed better qualities and were found up to the task in North Africa, when the counter-offensive began against the failed Italian invasion (Operation Compass), where 200 Mk.VIs (chiefly with the 3rd Hussars and the 7th Armoured division) formed the backbone of the British armour, together with 75 Cruisers and 45 Matildas. Despite their feeble protection and machine-gun armament, they performed well against lightly armoured Italian vehicles and tankettes, being particularly suitable for fast outflanking maneuvers against the retreating Italians, capturing many prisoners.

The British lost many tanks, but the 2nd RTR was probably the most successful in these kind of operations, retaining most of its forces until February 1941. Mark.VI tanks in active service gradually degraded with the arrival of the Afrika Korps. They soldiered on until early 1942, many being sent to Greece, where they formed the bulk of the 4th Hussars and other units, and again in Crete (3rd The King's Own Hussars), and Malta.

https://www.tanks-encyclopedia.com/w...light_MkVI.php

I know people don't think they need to back up what they say with sources but it is helpful nonetheless when they do

[Charles M]

These Mk VIs used in the Mediterranean were NOT Mk VIc versions. This was thoroughly researched for ASL (unfortunately a long time ago). I will try and get sources for you. Some of mine were lost when our under build flooded.

Your quotation makes no mention of Mk VIc or 15mm guns.

[DRG]

The game OOB that will be released with the next update ( whenever that might be ) has the 15mm Mk VIc service date end 7/40 and non 'c' version used earlier and later in the Med use a .50 Vickers

[Charles M]

Thanks. My best source is B.T. White's British Tanks and Fighting Vehicles 1914-1945, Ian Allen, 1970, p. 50:
"The Light tank Mark VIC was used in small numbers by the 1st Armoured Division in France in 1940, and, later, a few tanks of this type were with the garrison of Malta". A letter from the tank Museum in Bovington dated 28 September 1987 said pretty much the same thing, although the writer, E. Bartholomew did add that one was sent for trials to North Africa. There is a photo of this next to a Covenanter specimen in he desert but I cannot recall where. It may be in Duncan Crow's British and Commonwealth Armoured Formations, but my copy died in the flood and a replacement is with friends in the UK and currently inaccesible.