20mm or 50 cal (~12-13mm) for Anti-personnel use?

I think the SdKfz 222 was a good way of hauling around a 20mm gun. Though I'm a bit biased because of its v8 engine and independently sprung suspension.

Though the 222 had its shortcomings, and perhaps a more effective way to deploy the 20mm would have been to make a copy of the British Bren carrier -- cheap and low-profile.

It's an interesting question as to why the Americans liked the heavy machine gun enough to put it on nearly every vehicle, whereas the Germans appear not to have used it very much at all in the infantry role. The Germans had suitable candidates, such as the MG-131 aircraft gun in 13mm calibre, but didn't seem interested in adapting them for ground use.

I wonder why there was this difference in philosophies regarding the heavy machine gun?

 

There is no doubt that in anti personnel use the .50 must have performed far better. Since it's success in the second world war the round is still widely used in US forces today. 50 cal. machine guns are mounted on humvees for anti personnel and anti vehicle uses.

Lets also not forget one of the scariest weapons to date... the .50 cal. BMG sniper rifle. International laws still exist limiting its use against human targets.

 

As you can see on the photo above the newer guns have not changed much from the original Browning design, a testament to its usefullness!

 

I'm not sure about 50. cal. machinegun production, but it must have been astronomical due to its usage nearly everywhere (including aircraft)

http://www.tarrif.net/wwii/guides/flak30_38.htm

Production 20mm flak guns:
Flak 30- 8K
Flak 38- 40K
FlakV (quad) 38- 3.7 K

 

Yeah, German armored recon units had a lot of self-propelled 20mm singles/quad. And their propaganda footage often show 20mm firing against ground targets.

Did the 20mm had a very good "shrapnel" effect?

 

Come to think of it, I remember these weapons being used to good effect against Luftwaffe fighters/fighter-bombers trying to take out Remenagen Bridge.

 

"shrapnel" I believe refers to time or proximity fused shels fired to explode above the ground and spread fragments over a wide area. I think 20mm rounds are too small for that, AFAIK the US 37mm had some sort of special anti personnel round but a 37mm round is a lot bigger than a 20mm. The 20mm is more likely to be standard fused HE designed to explode after hitting a solid target, it's advantage over 7.92 is that it will probably negate cover like walls that would stop an ordinary 7.92 round.
The german recon armoured cars and half tracks (Sdkfz 250/9) had single 20mm guns but I believe the KwK 30 L/55 (also main armament of PzII) is a different weapon from the flak guns that were L/65 so had a longer barrel, I wonder if they even used the same ammo, the Flak guns used a 20x138 but I could not find ammo info on the KwK beside a mention of AP, APC and HE (no shrapnel!). AFAIK the quad SP mounts (Sdkfz 7/1 and the PzIV chassis based) were not usually assigned to recon units.

 

There were no A/A proximity fuses developed to service by the Germans in WW2, certainly with elctronic technology in WW2 it would be difficult to get one to fit into a 2cm shell and still have an explosive component.

2cm shell (kwk 38 flak 38 etc) were fitted with AZ47,48,49 series or Az 5045 all were direct action fuses the AZ 5045 was the most common type. The shells had a self destruction actuator either by tracer (direct flame or heat diaphragm) or later by spin decay.

KWK AP round lacked the fuse and relied on the self destruct element for the bang! There was also an AP shot with tungsten core, no doubt these were short lived as tungsten was a scarce resource.

The old MK17 18pdr shrapnell shell which is a classic timed fused shell requiring direct observation by forward observation officer to correct for effective air burst.

The promimity fuse which was used with medium and heavy AA gun in Allied service from 1943 bursts in near vicinity of a large object such as an aircraft or the ground, but most poximity fused shells were reserved for high value applications such as V1s and later Kamakazies. It was not until the Ardennes that field artillery used proximity shells.

To acuractly use a smaller weapon in air burst would require the gunnery officer to accurately calculate the target distance against the tracer setting for self destruction, for example for a 40mm Bofors the distance is short self destruct 3500yards and long self destruct 5500yards and note there is no way of ajusting this it is either, or. The same applies to the light guns such as the Flak 38 but obviously at closer range about 3000yards max (most people struggle with range finding at 1000yards).

Therefore In all fairness I would think "woofy" was using the term ["shapnnel" effect] in its coloquial usage as an alternative to fragmentation effect which might be more correct.

Steve

 

Nevertheless speaking of the German Flak 2cm you have to bear in mind that these guns were issued in very small numbers and therefore had to be used with care, as too rash an employment at the FEBA would deprive the proper recipients of air defense when needed.

Proper employment would be in the vicinity entities that were worthy of protection, such as HQs, artillery and mortar batteries, depots, etc. Wasting the Flak on the FEBA, where the infantry had their own support weapons (heavy MGs and mortars) would be a risky venture. And besides there weren't that many light flak pieces to go round.

Ditto for the famous 8.8cm. This had this emergency use as an AT weapon (and a very good one at that) but in doing so it deprived the "backoffice" of AA defence. And the 8.8 had so much use because in fact the 3.7cm and 5cm proper AT guns sucked big time (as some Americans say) !

 

The quad50 was an excellent weapon that could serve well on the ground with the reasons people said already. But not to discriminate the German 20mm, this weapon could tear open sandbags, rip buildings down and could cause men to explode. Both weapons were a match for each other but the Germans lacked the porduction capabilities.

 

Yes, it had a canister round which was quite effective against Japanese charges in the Pacific war.

Axis History Forum • View topic - US 37mm Canister Round ?

The canister round seems to have been used in many medium and large caliber weapons, but there's surprisingly little information about it in popular sources, which mostly concentrate on HE and AP rounds. It's still in use today, on US Abrams tanks.

 

Canister rounds were available for 90mm and 105mm rifled guns as well. For some time there were no 120mm canister rounds due to the absence of percieved need. Circa. 2004, the 2d Iraqi-American War happened and the US Army was fighting urban armored battles at close range. Interest for a anti-personel shell deadlier than the 120mm MPAT/HEAT revived and so a canister round was designed and fieled. The new canister round has a tungsten ball payload, a heavy metal that is extremely unhealthy. It almost goes without saying that since those who are shot with it are people whom Uncle Sam wants to be dead, this did not caused undue concern.

 

I knew olnly the western allies used proximity fuses in WW2 but time fuses were widely used since Henry Shrapnel introduced them in 1784! I acrtually remember reading that most early WW1 ammo was shapnnel and they switched to contact fused HE as it was not very effective agaist entrenched troops. Anyway a proximity fuse for a flat trajectory weapon such as the 20mm would have made no sense for ground fire even if technically possible. I found no mention of PzGr 40 APC (tungsten cored) for the Flak though it could have made sense agaist Sturmoviks, so my doubth remais as to how much commonality existed between the KwK and the Flak 20mm guns. Also why did the Germans believe 20mm was too light for AA use and tried to switch to 37mm wherever possible, or at least quad 20mm mounts, while the Allies thought 12.7 was OK? the ground attack 190F and G were pretty tough beasts though the 109 was not.

 

I don't think tungsten is that toxic, I believe tungsten alloy tools are quite common, are we possibly talking depleted uranium here?

 

The Germans had a very limited supply of tungsten. The amounts that they would have had to expend in AA fire probably made this usage prohibitive.

The Western allies didn't really see that much in the way of ground attack. The Germans did especially in the east. 37mm has a considerably longer range as well as being more effective vs harder targerts such as the Stormovick. As for the Soviets their 14.5 probably had enough punch to take out the 190s but I'm not at all sure what their AA thoughts were (was the 23mm of WWII vintage?)

 

I'm pretty sure it's less toxic than lead. A lot of the European powers use tungsten for their sabot rounds the lower or lack of toxicity being one of the rationals. Unless you consider the effects of high velocity chunks of metal toxic.

 

AFAIK the main soviet light AA caliber was a 37mm, also remember reading about an AA SP armoured mount (ZSU-37) that was so "optimized" for it's secondary ground fire role as to be nearly useless for AA. The Brits fielded some SP 20mm AA tanks (the 40mm were just prototypes I believe) but then retired them as the Luftwaffe threat did not materialize. I believe US stayed with 12.7 until they built a 40mm SP twin mount (think it came into service after Korea and they were unsed in RVN in a ground role) so the love affair of the US army with the browning went on for a long time, the big German losses to light AA during Bodenplatte makes me believe they were not all that wrong about it.

 

The Mk17 18pdr was fused with a No.80 fuse which was timed & percusion. Most shells whether HE or Shapnell could be fitted with either timed or percusion or both, sometimes all is required to set the fuse to impact only is to disable the timed function. If field artillery fired percussion only against entrenchments particularly in soft ground most shells except a direct hit would have zero effect at least an air burst by shrapnel gives a multiple chance of hitting some-one.

The tungsten shot is 2cm Pzgr Patr 40 L'spur. The standard AP round was 2cm Pzgr Patr L'spur m Zerlegung, a Standard HE round is 2cm Patr Sprgr l'spur. The rounds were used by both Flak and KWK weapons. As I said the tungsten was probably short lived and rare which means the main difference between the AP and HE round was the removal of the AZ5045 fuse and refitting of the fuse cap. IN AFV use the difference was the use of 10 round magazine rather than the 20 round mag. used in A/A weapons.

The number of IL2s brought down by 2cm A/A must be subjective to say the least, except in heavy concentration all light weapons be it over sized Mgs like the 50 cal M2 or the 20mm cannons, are to discourage low flying aircraft. There is positive evidence of 2cm Flak being used as effective Anti-tank role even to the end of WW2, There are numerous photos of Shermans destroyed by 2cm Flak- ie 2cm Pzgr Patr 40 L'spur.
I was not advocating the use of promity in 2cm AA for ground use. The reason why promity fuses were developed was for A/A use not as a sophisticated shrapnell shell. Watch the films on the Kamakazies, observe the number of Light AAA 20mm and 40mm bursting behind the target, it is a cost saving measure with a promity shell the shell may burst close enough to do some damage to the aircraft and I am talking about distances of less than ten metres, this is why an air burst 2cm would be fairly pointless in open ground use, the troops would have to be very close to the epicentre to be injured although incendary may improve lethal effect. In the ground role 2cm like 50cal is best used against building, light vehicles and rare banzai style charges, but it has to be remembered that most such charges were broken up by squad level rifle cal. Mgs correctly positioned.

Just to make matters clear there were no promity fuses for shell smaller than medium A/A eg 90mm and 3.7inch to fit a proximity fuse such as the T98 it was necessary to remove 130gram explosive pellet, a 40mm bofors shell has only 65grams as a charge. A timed fuse was experimented with for smaller 20mm to 40mm shells but to make robust enough it decreased to content of the shell too much and both Allied and German designers came to same conclusion that an impact and self destruct fuse shell was most effective.

The Soviets used rifle calibre weapons in single pair and quad mounts, 12.7mm both Russian and US ( inc. 1000 quad M17s) they had a 25mm Bofors LAA but it was very rare. the 23mm AA is Post War as is the 14.5mm MG although 14.5mm A/T rifle were used is a supposed AA role. They would also use anything else they could find like lash up aircraft cannon. There was also a twin armoured 20mm cannon mount which could be an unidentified light tank mount or possibly an armoured train but rare, seen in one film only.

40mm Bofors were mounted on turretless Crusader tanks during the Normandy landings. The US 40mm twin was the M19 which was Korean War usage. A half track 40mm was used in the Pacific as M15special and a similar extemporisation called T34 used in Korea. Both the US and British had Truck mounted 40mm Bofors.

There is little evidence of Soviet 37mm SP being used in WW2 rather like the M19 it was built during WW2 but probably did not get into battle. The soviets did however use the M15 37mm gun 50cal combination multiple gun motor carriage supplied under lend lease in small numbers.

Totally off topic Tungsten is a heavy metal and like lead in solution it is harmful.

Corrected

 

The cannister shell used by 37mm gun were a hang on from WW1,the USA was still using the 37mmTR trench gun mle1916 (French) as the m1916 until the outbreak of WW1 as a training weapon often attached to M2 105mm howitzers (to save costs) and of course it was the armament of the 6ton tank. Some obviously far sighted individual thought that the M1916 style cannister shell could be of benefit to the modern A/T weapon. Some British 2pdr tanks used these cannister fitted to a British cartridge.

The only other cannister shell I am aware of was the T18 for the 105mm M2 Howitzer.

They were not popular with artillery commanders as they severly shorten the life of gun barrels, no doubt the gunners quite liked them!. The effect on gun barrels can be judged by a story in the book Vietnam Tracks by Simon Dunstan that a tank of the Australian Army lost 18inches of it 20pdr gun whilst firing cannister.

There was a design in WW2 for the Yamato Class battleship to use a form of cannister shot (more akin to a cluster bomb) from its 18in main armament against distant air formations.

Steve

 

I believe the germans called Panzergranate 39 all "normal" AP rounds and Panzergranate 40 the tungsten cored ones regardless of caliber. So you will have a PzGr 40 for all KwK and PaK weapons but they are not the same thing. For example at least five different PzGr 40 existed just for the 75mm, (L/24, Pak 40, KwK 40, KwK 42 and the adapted French WW1 guns).
In the end I think "Panzergranate 39" is just a long winded way to say "AP" and "Panzergranate 40" to say "APC" so by itself is not enough to identify ammo.
The ammo for the Flak 20mm certainly had little in common with that of the aircraft 20m guns (MG-FF, MG-FFM and MG 151/20) so I was wondering if the KwK and Flak were different as well, possibly they used the same shells and fuses with different cartriges. The KwK of the Panzer II and Armoured cars were primarily ground weapons not AA weapons occasionally used in a ground role so it's interesting to understand how similar/different they were from the Flak.