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

50 cal. machineguns were everywhere in the US Army- halftracks, jeeps, etc. And still are.

Their opposition fielded 20mm guns in large number. Which was the more useful weapon against infantry opposition overall?

 

A quadruple mount of four .50 M2HB guns with a single gunner situated behind an armored pod was used by U.S. AA battalions in either a towed trailer or mounted in a half-track carrier (M16 AA half-track). With 200 rounds per gun in a powered tracking mount, the guns proved very effective against low-flying aircraft. Towards the end of the war, as Luftwaffe attacks grew more infrequent, the quad .50 (nicknamed the Meat Chopper) was increasingly used in an anti-personnel role. Snipers firing from trees were engaged by the quad gunner at trunk level - the weapon would cut down and destroy the entire tree, and the sniper with it.[27][28]

http://en.wikipedia.org/wiki/M2_Browning_machine_gun

 

I'm wondering if the single-barreled 20mm was too big, overpowered, and clumsy for anti-infantry work. (and with only 20 round magazines)

 

"The .50 caliber machine gun is primarily an anti-vehicular weapon. Its weight, and the weight of its ammunition, make it unsuitable for mobile infantry use. However, in semi-fixed positions such as the MLR in Korea, or mounted on vehicles in file, as in the withdrawal from Chosin, the weapon is magnificent. Its great range and striking power make it deadly in enfilade against troops staging for assault. Again, these capabilities make it ideal for quick reaction against machine gun and mortar positions on heights overlooking road communications.
Against massed infantry attack over ground with relatively constant slope, as against the Chinese human wave assaults on our MLR such as at Vegas, the M2 is a truly terrible force. For mobile deployment, Quad .50s mounted on half-tracks are devastating, going over the hills like a vacuum cleaner. http://www.rt66.com/~korteng/SmallArms/jpg/quad50.jpg"

 

The Flak30 ground mount



Flak 38 mount


No higher resolution available.

 

Antiaircraft artillery detachment armed with Quad 50s, Suwon, Korea, June 1950

 

I forgot to mention that the .50 cal M2 is 12.7mm.

 

Great pics, and wtf..the senior NCO in the lower photo has a knight's cross!

I've aware that these 20mm guns were deployed from trucks/halftracks into action..and sometimes even manhandled. Were they worth it? Seems like a really expensive, clumsy and exposed way to deliver direct fire against protected infantry. Not to mention, they need a few men to fire.

Isn't the 50 cal. enough for this sort of thing?

 

It seems that they would make great targets if used for direct fire. The single M2 ground mount could and did do a good job for that.

 

yeah, definitely. I've seen 20mm manhandled by German panzergrenadiers for urban warfare maneuvers. (real photos)

And I remember this, lol:

 

I think this mount (and with much greater ammo capacity) would seem more economical than a single 20mm cannon.

 

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M51 Quad .50-caliber Machine Gun on Trailer Mount (TM 9-223, Twin Cal. .50 Machine Gun Mount M33 and Multiple Cal. .50 Machine Gun Mount M45, July 1944)​

M51 Multiple .50-Caliber Machine Gun (“Quad Fifty”)

Every gun section in the 898th was equipped with one quadruple mount .50-caliber MG. These truck-drawn, trailer-mounted guns were capable of pouring a deadly hail of lead at low-flying aircraft. They were also devastating against ground targets, although as an automatic weapon over 11mm in caliber, by the international conventions then in force, this weapon was only to be so employed “in self defense.”

M51 Quad .50-caliber MG.

 

"Light flak guns are especially useful in combatting surprise attacks, because of the rapidity with which these pieces can be put into action. The 20-mm Flak 30, for example, can be put into action in about half a minute, and in extreme emergencies all light flak guns can be fired (although with a limited traverse) from their mounts. In addition, it is known that self-propelled models of the 20-mm and 37-mm calibers exist and can engage both air and ground targets. Like the heavy guns, the light guns in the field are usually fitted with shields for protection against small-arms fire. They are also fitted with flak sights and/or telescopic or linear sights, and carry armor-piercing ammunition in addition to percussion-fuze high-explosive ammunition. Light flak guns may engage ground targets, especially "soft-skinned" vehicles, at ranges of as much as 800 yards, but are most effective at ranges up to about 300 yards."

Lone Sentry: Tactical Employment of Flak in the Field (U.S. WWII Intelligence Bulletin, November 1943)

 

The US also used the M2 in a lot of places where other countries used 7.62 mgs. I believe it had a bit lower rate of fire but in the single mount was very accurate. Didn't a Marine sniper use one in Vietnam a lot? I think mostly he fired single shots with it as well.

 

Gunnery Sergeant Carlo's Hatchcock used an Ma Duece fitted with optics at least once in RVN. I forget the exact distance but I believe it was in excess of 1900 yards.

 

I think the Germans normally used the light AA guns in direct support fire during attacks because they could engage from outside normal rifle range, most pictures I've seen are consistent with that use, the 20mm manhandled by German panzergrenadiers ealier in the thread is probably an "exception to the rule".
Though horribly vulnerable to any sort of AT gun (and possibly ATR and .5 MGs as well) they had a sort of "immune zone" against normal infantry weapons. Germany did not deploy any weapons in the 10-20mm range (barring some adapted aircraft guns) so the 20mm filled the gap of "very heavy MG" as needed to complement the tripod mounted MG34 or MG 42s. High velocity 20mm rounds can be a lot more effective against troops in cover than 7.92 ammo.

The the small magazine makes me think aimed bursts against possible strongpoints rather than spaying supplession fire. I recall no picture of german 20mm guns similar to those of british wickers HMG groups surrounded by clouds of water vapor and small mountains of spent cartrige cases.

IMO most instances of ground fire by the US .5 quads were more defensive in nature, for attack there was no need to expose vulnerable half tracks when plenty of tanks and mortars were available, the frequent inclusion of the vehicles in mobile columns in Korea was probably not intended for AA protection though.

 

I remember the Germans occassionally use 20mm flak gun half-tracks for antipersonel work. An after action report of the 82d ABN Div noted that an attack was blunted when the Germans began to cut down the paratroopers with SP flakguns. I suppose when you don't have tanks anything that has gun and armor would do.

 

The US Army had the T10E1 twin 20mm mounting in a Maxson turret on the M3 half/track but it failed to impress and 109 of the 110 built were rebuilt as M16 with quad 50cal.

Furrther many trailer mounts in ETO were scrapped and the turret fitted to surplus M2 Half track becoming the substitute standard M16B.

Recently a Canadian sniper team in Afghanistan managed the comfirmed record for sniping using a modified M2 HB firing in single shot mode and of course an advanced sight.

Steve

 

Ah, yes, lots of infantry in the sky in these pics. Either that or the Germans really were 1000' tall after all

Seriously now, these kind of weapons had AA as their primary function, with a secondary capability as anti-armour as self-defense. Of course this does not preclude other use as circumstances dictated, but priority was for the design purpose.