Tank MGs - how powerful are they ?

[Jaska.]

This is a question I've occasionally wondered.

How does a tank-mounted mg compare with its infantry-versions ?

The MG 34 in, say, a Pz III. Is is comparable to a MG 34 in an lmg role or is it closer to a HMG ? I'd suppose an lmg, but I'm not sure. You don't get the "firepower" rating of tank-mounted mg's anywhere.

I suppose a tank with 3 mgs (such as a Stuart) would be more effective than one with only one ?

[SgtMuhammed]

The major difference will be accuracy, range, and ammo. Being mounted makes the gun more controllable and so more accurate at longer range. Plus a tank can carry more rounds than the dismounted gunner.

[Jaska.]

I was thinking along those lines that it'd be more accurate, but by how much ? I don't suppose there is anyway of knowing a tank mg's FP-rating ?

[Oddball_E8]

well... ive never fired an mg off a tank (or an mg at all really) but when playing WWII online i get the distinct impression that its like shooting an mg with a scope, but the "mounting" doesnt increase the accuracy by much since the muzzle flash kinda blinds you... so whilst short bursts are very accurate, sustained fire isnt...

but thats just off a game, so it might not be valid at all hehe...

[JasonC]

My subjective impression is that the firepower of tank MGs is roughly between a German LMG and a German HMG, or about 100 FP at the close range window. It is worth some testing though.

Also as an empirical matter, I find range definitely makes a difference, and the real way to exploit the armor is to use it to shove the MG right up under the target. Medium tanks with 2 MGs driven within 100m rout squads in 25% cover. To me it is clear that means the FP is well above the German LMG level, because LMG teams are essentially nuisance weapons that can only pin men moving in the open.

A related issue is the FP of bunkers. Log bunkers seem to have a firepower somewhere between an LMG and a tank. The conrete 3 MG ones have much higher firepower, at least equal to a German HMG team and perhaps more like double that.

A last important consideration in practice is the ammo load of vehicle MGs. Full tanks typically get hundreds of MG shots, enough to hose continually when they have targets. Light armor on the other hand can be limited to squad like amounts. I find in practice that light armor with 60 MG shots or less, if they fire at enemy targets in full cover and at range, pins stuff certainly, but is not deadly unless they catch men in the open. Full tanks in platoon strength driven aggressively, on the other hand, can break entire companies in decent cover. Only trenches and the like (10% exposure) can resist (pinning but recovering when fire shifts or lifts), for those you need HE.

Also as a practical matter, once rocket infantry AT becomes available, tanks have to stand off enough that their MG firepower declines significantly in effectiveness. The Russians remain vulnerable, since they are stuck with 40 meter range RPG tank hunters, and ineffective ATRs. But Americans, Brits, and Germans with zooks, piats and schrecks, will intimidate tanks into standing 200-300 meters away from likely infantry positions. Along with decent cover and "skulking" if a unit attracts too much fire, that lets later war infantry ride out tank MG fire.

Desert terrain is another matter. Tank MGs are deadly in CMAK desert fights, unless defenders have trenches. Most other desert cover is 50% only (rocky, brush, foxholes), and rocket AT is generally not available. Skulking LOS blockages are also usually unavailable. As a result, single coaxials on several tanks are enough to suppress, or by driving into them with a full platoon, break essentially any amount of infantry in open desert fighting.

I hope those typical reality assessments are helpful. The actual FP relationship or typical pinning to breaking time in various types of cover, still deserves actual testing. Fine question BTW.

[The Coil]

One other difference - all vehicle MGs have a max range of 1000m, regardless of type (which is further confirmation that they are treated as something other than their unmounted counterparts). Not that this makes a huge practical difference, in that you're probably not going to be hosing targets 1000m off, anyway...

[JasonC]

Here is a test result, make of it what you will. I think it shows under reasonable conditions for use of MGs by tanks, that their MGs are at least as strong as foot HMGs. Their FP ratings, according to my test, are probably a bit worse than HMGs, but it doesn't matter. Other factors dominate.

3 runs of the test. In each case, 6 firing lanes. At the Russian end, in each lane, a pioneer squad (9 man, regular) in command (HQ +1 command only) in rocky terrain, with an "area fire" order somewhere else to allow them to be spotted. At the other end of each lane, German shooters of the same type. First run, LMG 42s, second run, HMG 42s, third run, Panzer II F models with main gun ammo zeroed out, leaving the coaxial MG only, with 108 ammo. The foot MGs are in heavy buildings and take no suppressing fire themselves.

Then I check the losses and unit states after 1 minute and after 2 minutes. I treat alerted and OK as fine, shaken and cautious as "yellow", pinned as its own, all the others as "red".

LMGs, 1 minute: -3 men, 4 yellow, 2 OK

LMGs, 2 minutes: -3 men, all OK

When the squads get to yellow morale they cease their area fire. The LMGs then lose sight of them, even just 100 meters away, in mere rocky terrain. 2 man teams can't spot!

HMGs, 1 minute: -5 men, 2 pinned, 3 yellow, 1 OK

HMGs, 2 minutes: -9 men, 3 red, 1 pinned, 2 OK

One of the HMG teams jammed in the first minute of fire. Its target was fine, the other rallied to alerted around the end of the second minute. Losses were certainly higher and the fire was effective.

There was still a tendency to "lose" pinned targets. Also, the 3 reds were all panics and still in position. This reflects the tendency to lose the target as soon as it hits pinned or worse, which keeps them hovering right below pinned. The men hit, however, do accumulate - that much higher FP will achieve.

Pz IIs, 1 minute: -2 men, 1 red, 3 pinned, 2 yellow

PZ IIs, 2 minutes: -11 men, 3 red, 3 pinned

The coaxial MGs do not jam, unlike the foot HMGs. The initial fire is not appreciably more lethal than the LMGs, but by 2 minutes in the men hit are beyond even that achieved by the HMGs. The reason is, the optics assisted coaxial never loses the target, once acquired. As a result, fire does not stop at the pinned level, and continues until the target breaks.

Once broken, the targeted infantry move out of their cover, exposing themselves further - and once routed, they get up and run. Running infantry in the open is dramatically more vulnerable, and that is where the Pz IIs got the bulk of their kills, hitting 7 men in 2 routed squads, only 3 of them before they ran.

So the actual kills against stationary targets in rocky were less than the HMGs achieved. But it did not matter - the Pz IIs gor a better overall morale hit performance, and following up against running men, more permanent damage as well.

The reason was not FP, it was superior optics allowing continual fire, once the targets were acquired.

Note that shooting at men in the open at range, this might not be a factor, and the HMG teams might be preferable. Their high FP might translate into easily pinning and breaking at longer range. But shooting into moderate cover at close enough range, the difficulty MGs have is losing pinned or worse targets, not hurting them in the first place. And vehicle MGs are better at that.

FWIW...

[Redwolf]

It is between light and heavy.

Another way to see that is the maximum range, as displayed by vehicles that are armed with an MG only. The maximum range of these MGs is between LMG and HMG. There's no reason to assume that the coax MGs in CMx1 tanks work differently from MG-only vehicles. The hull MG is a different question, it seems pretty lame, but I think this is mostly from ROF.

[DavidFields]

Great question. Interesting this was not settled long ago.

I have been surprised to find that I often find myself thinking of tanks as mobile MG platfoms--using that ability as much as the shelling ability. I work had to preserve those thin-skinned AFVs, in particular, for late battle clean-up.

I had wondered if that was doctrinarily consistent with their RL WW2 use. Yes? Reading An Army at Dawn, about the war in North Africa, I was struck by the descriptions of the overrun Allied troops being MGed by the tanks--including the escaping crews from destroyed tanks.

[but, then, I tend to think of tanks, anyway, as infantry support weapons, and am annoyed when my units have to go to AP rounds]

[Son of Hamchuck]

It would seem to me that the height of the gun platform relative to the target might have some bearing. A Panzer II's mg is close to 2 meters off the ground, where the hmg is maybe a third that, less if well dug in. At 100 meters that would be a significant advantage for the tank mg staying "locked on" with a better angle to the target as well. I'm assuming this is factored into the mechanics.

[JasonC]

I sincerely doubt it. Try putting a foot HMG team one level higher than a tank and see. The better spotting the tank achieves isn't a function of height, it is a function of its dedicated optics.