"M1917 vs M1919A4 vs M1919A6: When is an MMG an LMG?" Topic

M1917: water cooled, tripod mounted MG

M1919A4: air cooled, tripod mounted MG

M1919A6: air cooled, bipod mounted MG with stock

These three weapons were by US infantry companies and battalions in WWII. For example, rifle company weapons platoons were armed with the M1919A4. Parachute rifle companies were armed with the M1919A4 as a squad level weapon initially and then later received the M1919A6 IIRC.

The M1917 generally served as the battalion level MG weapon.

Let's assume the following for broad, wargame unit type classification purposes:

LMG: bipod mounted, belt-fed, rifle caliber ammo

MMG: tripod mounted, belt-fed, rifle caliber ammo

HMG: tripod mounted, belt-fed, 12.5"-12.7" ammo

Based on those definitions the M1919A6 is clearly an LMG along the lines of a bipod mounted MG34, M60, etc.

The M1919A4 could be classed as an MMG as would weapons such as an MG34, MG42, M60, or M240 when mounted on a tripod.

QUESTION: do water cooled weapons such as the M1917 deserve their own classification (a fourth category) or can they too be classified as an MMG to keep things simple?

I was reviewing our home grown WWII rules this morning and noticed that if both the M1917 and M1919A4 are classified as MMGs then an American rifle company would have an organic MMG stand (the company level M1919A4s) and might have attached battalion level MMG stands (M1917s).

We've always classified the M1917 and M1919A4 as being the same MMG stand for simplification purposes. Or should the A4 be down-graded to LMG status? That would seem odd since the A4 had T&E controls like other tripod mounted weapons.

Your opinion?

You are going to be in a bit of a quandry trying to classify the US MGs in similar fashion to everyone else's, as I've always been of the opinion that they won't fit the parameters.

British Inf Bns have Bren guns, definite LMG courtesy of the magazine and barrel change. The next weapon up is the Vickers (attached for Inf Bns, organic for other tpyes), which if you're happy to go with calibre is an MMG by comparison to the Bren, due to its sustained fire capability and belt feed.

German Bns of all stripes have the oddity of the GPMG, so same weapon serving as the Squad LMG with barrel change and short belt feed, or sat on a tripod with extended belt feed higher up the food chain (Coy/Bn). No water cooling, but quick barrel change compared to the Great War veteran weapons.

Red Army, similar situation to the British really, though the DP LMG has a drum mag and while capable of barrel change Squads may not have had a spare. The M1910 equates roughly to the Vickers, while the replacement SG43 relied on air cooling and barrel change.

By comparison the US kit just doesn't line up. The bulk of the Squad types have BARs, which is better than a rifle but not quite as good as a dedicated LMG. The M1919A4 is better in terms of sustained fire than the LMGs mentioned above because it can be felt from 250-rd belts, but can't sustain fire for as long as the M1917 because it's air cooled. The M1917 sits very nicely alongside the Vickers and M1910 because it's from the same stable.

If anything required a different 'tabletop' classification I'd say it was the M1919A4. The M1919A6 is far closer to being a true LMG, air cooled barrel, bipod mount, but had belt feed, though again the barrel will heat up very quickly if used like an MMG.

Gary

If anything required a different 'tabletop' classification I'd say it was the M1919A4. The M1919A6 is far closer to being a true LMG, air cooled barrel, bipod mount, but had belt feed, though again the barrel will heat up very quickly if used like an MMG.

Yeah, that makes sense. Given that US Parachute squads used both the A4 and then the A6, for purposes of keeping things simple it's probably best to treat the A4 more like an LMG than a true MMG. I'd rather not add a new category just for one weapon.

My classification system is:

- Rifle Stand (squad with no automatic weapons)

- Rifle-LMG Stand (squad with one automatic weapon)

- Rifle-XLMG Stand (squad with two to four automatic weapons)

- MMG Stand (two to four tripod mounted machine guns firing rifle caliber)

- HMG Stand (two to four tripod mounted machine guns firing 12.5/12.7 rounds)

Therefore, US Parachute Rifle Squads with a single A4 or A6 would be classed as Rifle-LMG while the typical company level or even platoon level (Armored Infantry) US Weapons Squad armed with a few A4s would be classed as Rifle-XLMG. IIRC US Parachute Rifle battalions also used the A4 as the battalion level MG so those could also be represented as Rifle-XLMG Stands.

LMG = air-cooled MG on a bipod.

MMG = air-cooled on a tripod or mounted coaxial with a tank's main gun.

HMG = water-cooled on a tripod. Water cooling allows for more-sustained fire, assuming enough ammo is available.

none-of-the above = larger than rifle caliber MGs (i.e. the .50" heavy barrel Browning).

I would have said the A4 counts as a MMG when used as such (in a dedicated MG unit) due to the fact that spare barrels and ammo would be in greater abundance and the crews were dedicated solely to keeping the guns firing. When used at the squad level it would have a much smaller dedicated crew and lower levels of supply which would affect the RPM more than overheating.
Much like the MG34/42, the same weapon fulfilled multiple roles with different crews, supplies and tactical emphasis.

Don,

How much of advantage are we talking about with water vs air cool? I've not found anything to indicate a big practical advantage for water over air cool with changeable barrels, especially at simple wargame level of granulsrity.

In my games I'm not really interested in splitting up the BAR, the Bren, bipod MG34, bipod MG42, etc so if it's got a bipod it's an LMG. Further, tripod MGs firing rifle calibre ammo are MMGs and tripod MGs firing anything bigger than rifle calibre are HMGs.

How easy is an M1919 barrel change? Might have to downgrade both A4 and A6!

Barrel changes are essential to keep a non-water cooled MG in a sustained fight. That said, most of us envisage MGs being used at ridiculously short ranges. I'd hammer my GPMG(SF) crews if they were firing at 'cinema' ranges.

The MMG role in the attack is 500m-3000m as one element of an integrated fire plan. As we approach the enemy they can keep firing longer than artillery or mortars as they are not firing HE. TO allow us to cover the ground they will fire thousands of rounds per gun…barrel change or water cooled is the only way to achieve this.

In the defence they are used at a similar range, often firing over cover into potential enemy forming up points. That has to be sustained as long as the enemy is attacking. Again, water cooled or barrel change.

One of the limiting factors for an MMG or a GPMG(SF) is the amount of oil the troops are carrying!

An HMG is anything of heavier calibre, often limited to .50 or 14.5mm.

How much of advantage are we talking about with water vs air cool? I've not found anything to indicate a big practical advantage for water over air cool with changeable barrels

The issue with air-cooling is that if you are going to involve in any sustained shooting, you will need to keep changing the barrels quite regularly to prevent them from over-heating. This will involve the gun taking a pause from firing, one of the crew removing the hot barrel from the gun (depending on gun design, this might be quite simple or a bit tricky), and then placing a cooler barrel to the gun. With water-cooled gun, you simply open the water-jacket and pour in some more water.

If you are in a prepared position, with plenty of ammo and water, and with little need to move, water-cooled gun would be a fine choice: you can keep firing almost non-stop as long as the crew keeps on feeding water and ammo to the gun. However, if you need to move with the gun, the water-cooled version has the disadvantage of added weight. The water-jacket makes the gun heavier, and then you need to haul around the water (in canisters) and if you want to still take advantage of that sustained fire ability you will also need to haul in a lot of ammo.

Also, if you happen to be British, you can use the water-cooled MG for brewing a nice cup of tea for the crew, though perhaps with less than perfect taste.

As above, water cooled MGs can basically fire forever as long as you keep feeding in belts of ammo.

In terms of long range accuracy, a tripod is better than a bipod, but ultimately the lightness or otherwise of an LMG is mainly about how much ammo the crew lug around for it.

As per Wartopias reasoning, if the A4 is being used as a squad weapon, I'd treat it as an LMG, tripod or not. If part of the weapons platoon, then treat as an MMG.

I usually only rate MGs as 'heavy' if they have significant AP capability – so .50cal, 12.7mm, 15mm etc.

I do differentiate between mag fed and belt fed, the latter being more suppressive than their mag fed mates.

For game purposes, I would give water-cooled MGs some sort of slight firepower bonus (over equivalent air-cooled guns) to represent their sustained firepower capacity, in following cases.

1.) The gun is in a prepared position, with plenty of water and ammo available. If the gun moves out of the position, the bonus is lost. This might be scenario specific, eg. allowed only if side is holding a well-prepared defensive position, or is launching a well-prepared deliberate assault on such position.

2.) The gun team has been assigned plenty of water and ammo bearers to haul around supplies. This might involve detaching riflemen from rifle squads to act in such a role. The gun can move around and fire with the extra bonus. However, if the extra ammo bearers are lost as casualties, the bonus is lost even if the gun crew itself is still remaining. Also, while the ammo bearers may carry personal weapons, they are mainly too busy handling their load to use them to full effect, except in close defense.

Some gamers or game designers might also want to represent some other special features, like the indirect pepperpot barrages that the British MG troops could be trained to perform.

the water-cooled version has the disadvantage of added weight.

Hence the term "heavy machinegun."

I'm not sure, but I doubt that the term "medium machinegun" was actually used during WW2. Was it? At least in US parlance water-cooled MGs were HMGs, and air-cooled ones were LMGs.

I would have said the A4 counts as a MMG when used as such (in a dedicated MG unit) due to the fact that spare barrels and ammo would be in greater abundance and the crews were dedicated solely to keeping the guns firing. When used at the squad level it would have a much smaller dedicated crew and lower levels of supply which would affect the RPM more than overheating.

This makes sense to me.

BTW: I think that trying to cram all of the automatic support weapons of WWII into a rigid LMG/MMG/HMG classification, where all weapons in the same category are identical, is rather clumsy mechanism.

I would rather see the guns rated by their actual performance, eg. by following categories:

a.) Mount type: bipod / tripod
b.) Feed mechanism: magazine / belt
c.) Cooling: air-cooled / changeable barrel /water-cooled

So a Bren gun for example could be classified as MG (bipod, magazine-fed, changeable barrel) and Vickers as MG (tripod, belt-fed, water-cooled).

Other possible features that could be integrated are rate of fire (normal or high) or the cartridge used (low-powered, regular, heavy (12.7 mm or more)).

I'm not sure, but I doubt that the term "medium machinegun" was actually used during WW2. Was it? At least in US parlance water-cooled MGs were HMGs, and air-cooled ones were LMGs.

I believe that is true. I had always viewed the use of "MMG" in the WW2 context as a rules construct (first used in WRG?) designed to reflect the advantages of the tripod as already discussed, but (as Martin mentioned) separating lighter weapons from those with significant AP capability.

Air cooled … you don't have to lug the water can with you … you already have enough to carry if you are part of a MG Tm. And I'd agree, anything .50 cal or larger is HMG. And an LMG does not have a tripod, only a bipod … Note: an M60 has both, is .30 cal and it's considered a MMG. An M249 has a bipod, is 223 cal. and is a SAW/LMG … So some general guidelines I use …

In British WWII usage an LMG was a bipod MG (eg the Bren), an MMG was a tripod MG (eg the Vickers) and the HMG was an MG that fired anything heavier than rifle calibre bullets (eg the 0.50cal Browning).

The US used LMG for air cooled 0.30cal MGs and HMG for other MGs. The BAR was not considered an MG as such.

The Germans used their GPMG in LMG form with a bipod, limited ammo and spare barrels and in HMG form with tripod, telescopic sight and plenty of ammo and spare barrels.

Everyone else seems to have classified bipod MG (including the BAR) as LMG and anything on a tripod as HMG.

Wargames Rules writers who want to distinguish between various types and usages of MG without detailing individual models of MG may find LMG/MMG/HMG useful classifications of increasing firepower with decreasing mobility.

"I had always viewed the use of "MMG" in the WW2 context as a rules construct (first used in WRG?) designed to reflect the advantages of the tripod "

What Leadgend said. My WW2 Vickers gun manual is entitled 'The Tactical Employment of Medium Machineguns', so they were certainly calling them MMGs in 1943…

Heavies were .50 cal BESAs etc.

In the British Army at any rate.

My rules aren't really that granular:
LMG-Bipod
MMG-tripod
HMG-.50 cal or similar.

The MG34 and MG42 get a dice bonus, I might consider the A6 for the same thing if I had any. MMG's and HMG's get a range bonus and more dice. HMG's get to shoot at AFV's (but at the same rate as an AT rifle, which is terrible at best).

I would say that any machine gun that has a stable (tripod) mount AND either a water-jacket OR quick-change barrel OR a very heavy barrel (such as the Japanese MMG) should be classed as a Sustained-Fire Machine Gun (i.e. an MMG in WW2 British terms). Anything else is either an LMG or an HMG.

While the M1919A4 had a tripod, it lacked either a quick-change barrel (like the Bren or MG-42) or a water-jacket (like the M1917 or Vickers MMG). These factors severely limited the amount of rounds that could be put down the barrel before it had to be cooled down.

The US Army used M1917s at Battalion level for SFMG/MMG support and M1919A4s at Company level for LMG support, so it seems to me that classing all of the .30s in a battalion as SFMGs/MMGs is over-egging the pudding.

Mark,

We use SFMG in our modern rules for those reasons. Seems that SFMG is used today while MMG sounds more "WWII-ish".

:-)