Belt fed LMG and MMG

Moderators: Laffe, Vis Bellica

User avatar
Truscott Trotter
Posts: 7584
Joined: Mon Sep 09, 2013 11:11 pm
Location: Tasmania the Southernmost CoC in the world

Re: Belt fed LMG and MMG

Post by Truscott Trotter »

CoC treats the M1919 as a MMG rather than a belt-fed LMG.

Not really it is a bipod belt fed LMG in some lists (US Para) and a tripod MMG in others (US arm rifles)
It is more about function and tactical use than about RPM

Archdukek
Posts: 5040
Joined: Tue Sep 03, 2013 11:49 pm
Location: Linlithgow, West Lothian, UK

Re: Belt fed LMG and MMG

Post by Archdukek »

The CoC Espana supplement has some rules for the kind of off-table MG suppressive fire which siggian is referring to if anyone fancied trying them out.
John

exchook
Posts: 141
Joined: Sun Sep 29, 2013 2:35 am
Location: Sydney, Australia

Re: Belt fed LMG and MMG

Post by exchook »

While a MMG does have a tripod, better sights and more ammo bearers it is still the weapon as that of a standard LMG.

The main factor which restricts the rate of fire of machine guns is the barrel.

The worst thing that can happen to machine gun team is to have the barrel overheat. It can cause the weapon to 'cook off' that is to fire uncontrollably whether the trigger is depressed or not!

That is why barrel changes are made.

It is also another reason why you do not see machine guns blazing away with 100 round bursts - watch the videos even from Afghanistan and Iraq these weapons do not fire long sustained bursts.

The 'average' machine gun has a 'beaten zone' of roughly 1sq metre at 100 metres (and so on 2sqm at 200m etc) that is the rounds fired will land somewhere within that square metre when the trigger is pulled. This does not take into account recoil as the weapon shifts during firing the beaten zone will move.

Given this beaten zone the weapon when used alone is not comparable to an arty barrage. The Vickers was able to complete this task because it was water cooled and not air cooled and could sustain a higher volume of fire for longer periods.

Placing the weapon on a tripod allows that weapon to hold it firing postion, but while it does this it also restricts the field of fire of the weapon. Even the recoil of the weapon can move the firing position of the tripod and this can move the fall of shot off target if the weapon is not resighted from time to time. Minimal adjustments can be made without moving the tripod. If the tripod has to be moved the weapon needs to be sighted again.

Given the phase in CoC is around the 15sec mark and the necessary pauses to firing the weapon needs to make I can see why the MMG is 10 dice.

Richard
Site Admin
Posts: 1690
Joined: Sat Aug 17, 2013 7:50 am

Re: Belt fed LMG and MMG

Post by Richard »

Okay, we now have two questions here.

Firstly the 6 versus 8 versus 10. for box, belt and tripod. The fact of the matter is that with any set of wargame rules one needs to draw lines somewhere. In terms of technical capability the MG42 is a very modern weapon with a high cyclical rate of fire which, when mounted on a tripod, is provided with a stable weapon platform making it more effective than the bipod mounted squad weapon. Comparatively, the vickers, or US the M1919, is an old 19th century derivative weapon which has a slow rate of fire.

However, the fact is that both the Vickers and the M1919 are water cooled and, as a consequence, can fire all day without issues (as was proved in the Great War) so long as you have liquid to top up the reservoir.

On the other hand, the MG42 (and 34) is an air cooled weapon which, if accuracy and continuity are to be maintained, can actually only fire in bursts. Indeed, it can only be fired in the same length of bursts which the bipod mounted weapon can achieve. As a result we ignored completely the theoretical 1100 rpm figures, and looked instead at the more typical 150 rpm. i.e. significantly less than the 500 rpm from the Vickers.

But that again is not the full picture. We then tempered that data with the fact that it is actually not the ability of a weapon to deliver x number of rounds across a full minute which determines its accuracy. It is just as important to be able to deliver a large number of rounds in a five second burst, and that is what the MG42 does very well indeed.

So, taking all of the above into account, we decided that both types of weapons had benefits which balanced out and allowed us to rate them equally. The rating of 10 as compared to the 8 of the bipod mounted belt-fed weapon actually reflects not an increase in rpm fired, but a marginal increase in accuracy due to the stable platform. Personally, I am happy with the weapon ratings as they are. They were based on long and careful consideration, including comparative studies conducted by the participants (like the one we have kindly been shown).

Secondly, there is the issue about what MMGs should be doing and the suggestion that they were chiefly used for area denial. This is a really interesting point and one which, again, I have studied at some length. In the Great War, my Great Uncle served in the Machine Gun Corps. AT the time, like the RFC and the Tank Corps, machine guns were recognised as a specialist branch of the service and, as a result, were formed into their own Corps. They became incredibly specialised and very good at devising and delivering machine gun barrages which utterly saturated vast areas of ground. This was largely, but not exclusively, used for flank or box protection for a friendly attack. They would create a curtain of firepower (along with the artillery) which would isolate an area of ground about to be attacked. This isolated the German defenders and stopped any reinforcements being sent to that area. The net result was that the attackers could make their attack unhindered by any counter attacks from the flanks or enemy support lines. All very clever.

The problem, or perceived problem, was that when an infantry formation was allocated machine guns to support it, the MGs were very tightly controlled by a relatively junior officer. He would site them he would decide what role they would take and, most importantly, he could overrule or ignore orders from the officers in the infantry unit, of any rank. This utterly pissed off senior infantry officers who were told they couldn't do what they liked with their MGs. The net result was that the Machine Gun Corps was dismantled after the Great War and MGs were subordinated to the infantry formations they served with.

What is particularly interesting about this, is to compare the practice in the MGC with that of the Germans. Their Maxims were always subordinate to the units which they were part of. As a result the Germans did what infantrymen always do with machine guns, they point them directly at the enemy and shoot at them. So, in broad terms, the Germans used them as a direct fire "super-rifle", the British used them as pseudo-artillery in an indirect fire role. With the dismemberment of the Machine Gun Corps the British Army largely ignored all the clever stuff they had learnt in the Great War and, like the Germans, used them in a direct fire role.

So, what we have represented is that "new" direct fire approach, as opposed to the "old", WWI, area denial role.

Hope that clarifies on both points. There were, of course, exceptions to both rules, but that does sum up the differing doctrines. I would suggest, having studied this at some length, that machine gun tactics reached their zenith in 1918, at least in Britain.

Rich

User avatar
remgain
Posts: 227
Joined: Sat Sep 21, 2013 6:23 pm
Location: Milano, Italia

Re: Belt fed LMG and MMG

Post by remgain »

Thank you Rich!!

Marco
We don't stop playing because we grow old; we grow old because we stop playing.

George Bernard Shaw

User avatar
Seret
Posts: 4107
Joined: Sat Jul 05, 2014 7:45 pm
Location: Kent UK
Contact:

Re: Belt fed LMG and MMG

Post by Seret »

Richard wrote:In terms of technical capability the MG42 is a very modern weapon with a high cyclical rate of fire which, when mounted on a tripod, is provided with a stable weapon platform making it more effective than the bipod mounted squad weapon. Comparatively, the vickers, or US the M1919, is an old 19th century derivative weapon which has a slow rate of fire.

However, the fact is that both the Vickers and the M1919 are water cooled and, as a consequence, can fire all day without issues (as was proved in the Great War) so long as you have liquid to top up the reservoir.

On the other hand, the MG42 (and 34) is an air cooled weapon which, if accuracy and continuity are to be maintained, can actually only fire in bursts. Indeed, it can only be fired in the same length of bursts which the bipod mounted weapon can achieve. As a result we ignored completely the theoretical 1100 rpm figures, and looked instead at the more typical 150 rpm. i.e. significantly less than the 500 rpm from the Vickers.
As an ex-armourer and someone who's fired both kinds of guns I'd say this is pretty much bang on. Although I'm not sure the poor old Vickers we had at the gunny school was capable of anything you'd call sustained fire any more!

Let's not overstate the desirability of water-cooled guns too much though. The availability of sufficient cooling water is far from guaranteed, and when it runs out you're pretty much buggered. About the only time you'll have more water than you need is in a static defence when you can have it stacked up ready. Like bolt action rifles it became obvious that water cooled guns were obsolete during WW2. The only reason either served throughout the war is that armies are glacially slow in adopting even the most glaringly obvious advances in small arms technology. Air cooled guns in manoeuvre warfare can provide more reliably high weight of fire and are more survivable.
I would suggest, having studied this at some length, that machine gun tactics reached their zenith in 1918, at least in Britain.
This I agree with less. Ask an infantry officer today how he uses his SFMGs and he'll talk about the kinds of things you mention in WW1 above. Along with mortars SFMGs form part of the fire plan. They aren't used against opportunity targets the way LMGs are. In attack they will be put on high ground to fire continuously over the attacking troops until they're too close, or they'll be put on the flanks if there's no high ground or for night attacks. They are used to provide screening fire like you talk about above. In defence they're sited to cover preplanned killing zones, just like the mortars.

The fact they started to be parcelled out to individual infantry units changed the numbers they were deployed in, but not really their role. Their main job to this day is to provide sustained fire against preplanned targets. IMO the dissolution of the MGC should be seen as an admission that MGs in the sustained fire role were too useful to small infantry units to be hoarded further up the food chain. The fact that guns were evolving to be capable of both SFMG and LMG roles cemented this.

In CoC the SFMG role would IMO be best represented by copious use of covering fire. The trouble is the 4" beaten zone you get in CoC means they don't really perform well in this role, any infantry section can do as well or better. Personally I would actually give an SFMG a greater capability to provide covering fire and a reduced capacity to engage opportunity targets compared to an LMG. I would be happy with something like 5d6 firepower but a 10" covering fire zone. These are not guns that are good at engaging fleeting targets directly the way an LMG does.

If you wanted to be really realistic or represent off-table guns (they're often 500-1000m from the objective) then you'd give them a beaten zone that was effectively a long narrow lane instead of the frontage of a terrain feature. CoC already includes a rule that forces supporting troops to cease fire when friendlies near the target, so minimal tweakage would be required IMO.

hedgehobbit
Posts: 163
Joined: Mon Sep 09, 2013 3:49 pm

Re: Belt fed LMG and MMG

Post by hedgehobbit »

One thought I had was to allow those water-cooled MGs, like the M1917, to remain in Covering Fire until the end of the turn, rather than the end of the next phase. That way you aren't using dice to each phase. Probably not realistic but it's a fairly simple rule to implement.

I'd also have them lose this ability if they ever moved as they'd lose access to their stockpiles of ammo and water. This way they would be more appropriate when defending.

User avatar
Truscott Trotter
Posts: 7584
Joined: Mon Sep 09, 2013 11:11 pm
Location: Tasmania the Southernmost CoC in the world

Re: Belt fed LMG and MMG

Post by Truscott Trotter »

Not a bad rule idea HH but is it worth the extra complication?

User avatar
sespe
Posts: 82
Joined: Tue Feb 11, 2014 12:34 am
Location: Southern California

Re: Belt fed LMG and MMG

Post by sespe »

hedgehobbit wrote:One thought I had was to allow those water-cooled MGs, like the M1917, to remain in Covering Fire until the end of the turn, rather than the end of the next phase. That way you aren't using dice to each phase. Probably not realistic but it's a fairly simple rule to implement.

I'd also have them lose this ability if they ever moved as they'd lose access to their stockpiles of ammo and water. This way they would be more appropriate when defending.
I actually like this idea. Gives power to a correct deployment.

sid
Posts: 276
Joined: Mon Nov 25, 2013 9:32 am
Location: Sunny Swansea

Re: Belt fed LMG and MMG

Post by sid »

I do think we need to distinguish between the British use of MMG and other nations. The majority of armies just put guns on tripods and turned enormous amounts of rounds into empty cases.

The British army was more scientific. Although as Richard says the MGC was disbanded after WWI, in WWII the Vickers were grouped in specific MG Battalions. So for example 53rd Welsh Division had their MMG support provided by 1st Manchester's. They would have 3 companies each of 12 Vickers and a fourth company of 16 4.2" mortars. Each company had 3 platoons of 4 MMG and the mortars were in 4 platoons of 4 tubes. Now the Division had 4 brigades each of 3 Battalions. Normally the British would keep a Brigade out of the fight so each Brigade would in theory have one company so each Battalion would only have a single platoon of 4 MMG. Not many but of course the guns were normally tasked to support the main effort so some battalions would have more support than others.

Roles in the attack would include using tracer to mark lines of advance, suppressing enemy positions, suppressing depth positions, shooting indirect onto rear admin areas, providing support against counter attacks.

Defence roles would include pre-planned targets especially at night, preferably with flanking fire (the old enfilade fire from a defilade position) with a dedicated Final Protective Fire (FPF) target on which the guns would always be set when not firing on any other task.

To return to the main point these Divisional Support Battalions were specialists and the men were as well trained and flexible as their predecessors from the MGC in the first war.

As to the above points regarding loss of ammunition and water if the guns were moved, I'm sceptical that this was an issue. The MG officers were experts in their field and would pre-plan alternate (different position covering same target as primary position) and secondary positions (different position covering different arcs/target areas. The movement and/or pre dumping of ammunition or water would be covered in that. Also extra bodies would be allocated to assist in any anticipated difficult moves. So if we assume the MG commander knows his job we can keep it simple by not having any extra rules in reducing the effectiveness of the guns.

Even today the British Army trains its GPMG (SF) commanders in all the dark arts of MG indirect fire. The guns are equipped with C2 sights (the old mortar sight) to assist in indirect fire, although this is mostly a harassing function. Unlike mortar men the GPMG (SF) commander does not have a fire control computer but makes do with a notebook and calculator to work out his fire plan!

With reference to the above comment that even with a tripod the guns jump out of true line, as an old British army MG platoon commander if my sections did not weight the tripods with sandbags, someone would get a serious beasting!

Also as mentioned, like mortars MMG should be quite far to the rear of the main position. In the modern British use of MMG (my only experience I'm afraid) the ideal battle range was 600 to 1100 metres. 600 as this is getting beyond the effective range of small arms fire and 1100 as this is tracer burn out, beyond which it is very difficult to adjust fire. Maybe use a template similar to that used by mortar barrages, however instead of square have it elongated and it does not obscure sight. To make it even more fun have the owning player of the MMG section place a marker on his board edge to indicate the rough position of the guns and any use of the long template must be drawn from this point. He could even move that point using a chain of command dice to indicate the difficulties in relocating the gun position.

Naturally there would always be occasions when the MMG would get caught up in the battle so we can pay the support points and put those lovely models on the table. But an alternate support option could be for a section of MMG. Unlike Mortar barrages these would not end at the end of the turn and would be easier to adjust using a line of sight from the aforementioned point on the table edge.

Post Reply