75mm Arty Too Expensive?

[John Kettler]

Jason,

If you're not a grog I'm not sure I'm ready to meet one. Wow!

Congratulations on producing the closest thing I've seen so far to the data I'm seeking. Will have to reread your meaty post when i have more neurons talking to each other.

Many thanks!

John Kettler

[Olle Petersson]

Originally posted by Shadow 1st Hussars:

Why does it take 81mm spotters less time to call in the arty than their larger caliber brothers?

Don't know if this was already answered, but...

It's because these mortars were battalion weapons, and thus more alert to calls from within their battalion. This is true for the Allies, and goes for the 3" mortars as well.

Edited (corrections in italic) 010307, 12:00 CET;

I'm more curious about the quick response time for the US 4.2" mortars, since (AFAIK) these were organised in battalions non-organic to the divisions, and thus Corps assets...

The British (leg) infantry divisions used 4.2" mortars as regimental artillery.

For the German Panzergrenadiers, the 81mm mortars were spread at company level from 1944 on, and should therefore pretty much show up as on map mortars only in CM. (You get them with each company.)

Their battalion mortars were the 12cm version.

The German leg units (such as regular infantry, fusiliers and VG) retained the 81mm mortars at batallion level, in addition to the 12cm mortars.

Why this one (the 12cm mortar) have such a lousy response time (in CM), compared to the 81mm version, is beyound me. This also goes for the question why it doesn't have any smoke rounds available. If using a historical TO&E the Germans are stuck to using on map mortars to set up smoke screens, unless they call for the regimental artillery.

Main source: "Armies of the second world war" by Greg Novak and Frank Chadwick. A set of sample TOEs for most armies in WW2. Supposed to present typical field strength, not book strength, but doesn't differentiate between the eastern and western fronts.

Cheers

Olle

[This message has been edited by Olle Petersson (edited 03-07-2001).]

[Guest aaronb]

I'll echo John's comments - great food for thought, Jason. And, while not definitive (not for lack of effort), it certainly does give some sense of the possibilities.

------------------

my armoured assets have about the half-life of a gnat in DDT

- Germanboy

[jasoncawley@ameritech.net]

The Germans did issue 81mm mortars at the comany scale. But they also retained 81mm mortars at the battalion level. The Germans never fielded 120mm mortars enough for its role in their TOEs, and it was mostly a regimental weapon when it was available. The Germans only made around 8500 120mm mortars, while they made 9 times that many of the 81mm variety. And the difference in ammunition produced shows an even wider gap in favor of the 81mm.

In actual unit returns from Normandy, I have examined more than 15 divisions without finding a single 120mm mortar actually deployed. But the infantry divisions have up to 84 of the 81mm in some cases.

The 120mm was probably more common on the Russian front, where the Russians were making extensive use of it (easily 5 times the scale of the Germans), and captured ammunition and weapons were probably more plentiful. It is also likely that the 120mm was more common in the middle period of the war, 1943 in particular. The reason being, little German ammo production for it, and eventually running out of captured Russian stocks after passing to the defensive.

[Olle Petersson]

Edited my previous post, as a result of further studies.

Cheers

Olle

[:USERNAME:]

Originally posted by jasoncawley@ameritech.net:

75mm shells vary considerably, but the most common weight given for German 75mm *HE*, is 13 lbs, 6 kg. So it is a much heavier physical item. But the size of the bursting charge for German 75mm varies. The largest type is listed as 860 grams bursting charge, and that type was *capable* of being fired from, for instance, the L24, L43, and L48 guns on the Pz IV series (where I got the data).

But that doesn't mean that is what they had. Another HE type for the L43 and L48 guns, had only a 454 gram bursting charge. A HEAT round for those types had a 524 gram charge. Other HEAT that could be fired from the L24 or the longer L43 and L48 had charges from 555 to 604 grams. Another fellow has cited the figure of 680 grams for at least one version of HE fired by the longer gun in the Panther, but I can't independently confirm that number.

I am aware that HEAT is a relatively poor HE round. But were they so aware of the fact? That is, did HEAT get issued as a supposedly duel-purpose round? Seems possible. The Germans made 4 million HEAT rounds for high velocity 75mm, along with 5 million AP and 8 million standard HE. Production of HEAT for those guns trailed off in 1944, though, and ceased before 1945.

What I most sincerely doubt, is the notion some seem to entertain as possible, that since a 860 gram HE round apparently existed for a range of German 75mm gun types, that must be what they always fired when firing HE. They made another with a 454 gram charge, and I haven't been able to find out how many of those, compared to the other type. But they certainly made 4 million HEAT, with smaller loads than the peak one, slightly more than the lesser one.

The HE load figure cited by one fellow for the higher velocity Panther gun, had one ammo type 5/4 as high, and there is this Sprgr-KwK (34) with 3/2 as much. But I have seen no evidence these types were common, nor rare really. No one has given any production or field deliver numbers for any of the types, that I know of.

U.S. 75mm and similar types, also varies. The 76mm had a small bursting charge of 390 grams, while the slower 75mm short had a 690 gram bursting charge. That puts one of them 5/4ths the explosive of the German 81mm, the other 7/10ths. I have not been able to find the gram of HE for the pack howitzer, used in the U.S. airborne. I think that is basically the same gun as that on the M8 HMC. Those two are the likely sources of the 75mm artillery module for the U.S. side.

[This message has been edited by jasoncawley@ameritech.net (edited 03-06-2001).]

I believe the US 75mm Pack howitzer fired the same Mk84 shell as the Sherman 75mmL40.

Most data contradicts the US uber sherman had a super gun. Even your data points out that most german 75mm had at least as good if not better. I have brought this up to BTS attention and they basically dont comment.

Heres a website that shows fillings for US shells.

http://library.atlantic.edu/amatol/p-061%20The%20Plant.html

It must also be considered that 75mm arty gives itself away with the whining of the spinning shell coming in. Mortars have the distinct advantage of coming in quieter. The mortor shell also lands almost vertical. It spews its fragments out very efficiently while the arty buries them or sends them skyward.

If I had a choice, I would not choose to come under 81mm mortar fire if moving in the open. If I were lightly dug in, then I would not want 75mm arty poking around my position.

[This message has been edited by :USERNAME: (edited 03-07-2001).]

[IPA]

Slightly on a tangent. If availability was the only contributing factor to points value, for American and British Airborne engagements 75mm Arty is possibly underpriced.

Assuming that an Airborne division is isolated (I'll use the British, though I think the US AB Div would be similar, but with 8" mortars).

A British AB Division typically had 24 75 Pack Howitzers divided into three batteries of 8. One battery would be allocated to support each Infantry Brigade (2 Parachute and 1 Airlanding, three btns each).

Each Parachute Battalion had a platoon of 6 3" mortars in the support company, which was an integral part of the Battalion and could provide 100% dedicated support.

Each Airlanding battalion had two mortar platoons of 6 3" mortars.

Each 75 Battery was divided into 2 troops of 4 guns. Therefore, a battalion could expect one troop of dedicated support 2/3 of the time.

75mm Spotter costs 88

3" Spotter cost 116

I'd be grateful if Jason could somehow factor this in into his blast point equation by adding a weighting for availability of AB Arty and Mortars.

Thanks

Peter

[jshandorf]

I guess for me what it comes down to is that I never buy 75mm arty. It just seems like a waste and never has it been very effective when I did buy it.

The only way I would buy it is if the price comes down.

jeff

[jasoncawley@ameritech.net]

Still on the deployment of 120mm mortars question. I don't find, in practice, the pattern Olle suggests. I am aware that 120mm mortars were made part of TOE. But the lower-down use of the 81s, and the relatively absence in practice of 120's in the numbers the TOEs had, don't quite fit.

First let me limited the universe I found detailed data about, on this subject. I am using other people's research to examine this question, and the case I have the data for is the Normandy fighting. Russia may be different, and other times likewise. And I have to further limit the data set, simply because detailed info about the mortars deployed is not available for every formation, and when it is available the level of detail varies from one to another formation.

With those provisos, here is what I find. The standard deployment of the 81mm was 6 for the battalion, plus 2 per company, making 12 per battalion all told. Cases that *exceed* this number of mortars, are very rare. But engineers only have the 2 per company. And SPW mounted Panzergrenadiers, I find the same as the engineers - 2 per company, no battalion mortars. The motorised Pz Gdr battalions are like the leg infantry. Recon battalions are sometimes 2 each, sometimes like the leg infantry with both 2/company and 6/battalion.

But then, the units fail to have their TOE of these mortars, most of the time. The only division I was able to confirm had *more* than the number you get with the above allocations, was the 3rd FJ. That was a large division, with 9 infantry battalions, plus 1 recon and 1 pioneer. It had 124 mortars, with up to 16 in particular battalions. This may just mean "square" companies and a larger battalion battery, 2x4 + 1x8. Or it may reflect 1 battery of 4x120mm at the battalion level, since the mortar numbers I saw for this unit do not specify caliber, just number of tubes. The regimental level does not have mortar companies in this division, incidentally.

In the case of a line infantry division, the above allocation can mean up to 96x81mm in a division. (6 inf+recon+engineer=8 battalions, then 12 each). Only one infantry division had that many - the 352nd - and no panzer, that I found numbers on anyway.

I found 2 mentions of 120mm mortars in Normany - 12 of them a kampegruppe formed from both PzGdr regiments of the 9th SS after those became somewhat depleted in action, with 12x120mm in support of the "doubled regiment(-)". And the 272nd infantry division lists 54 "medium" and 32 "heavy" mortars, and the last almost certainly means 120mm. The 716th infantry (static), had 33x50mm, 44x81mm in the battalions, and 29 mortars in independent ad hoc firing companies, which may have been 81mm or 120mm.

In the cases where I did find numbers of the mortars in the mobile divisions - which I only found in about half the cases - the number of mortars was somewhat lower.

Here are the mortars per division for the formations I found numbers on, ignoring the 50mm in the 716th as too small to matter. Other that the ones marked (*, ?) these are all 81mm -

3FJ-124, 16LW-54, 77th-45, 85th-76, 243rd-51, 265th(KG)-16, 272nd-86*, 275th-18, 277th-58, 326th-56, 371st-72, 352nd-96, 353rd-84, 709th-71?, 716th-73?, PzLehr-24, 9SS-78*, 12SS-70, 21Pz-6 (engineers), 17SS PzGdr-99

* - 120mm present

? - " may be present, unclear

Some averages - average infantry division - 66 mortars. Average mobile division - 55 mortars. The range is wide, with ~1/5 divisions way below average (24 or less), and 1/6 way above it (96 or more).

My purpose in giving this sort of data, is simply to impress how little TOEs can sometimes mean for particular items and particular formations, at this stage of the war, in the German army. There are a lot of ersatz substitute measures going on, and unit strengths vary considerably - even before combat, let alone after a month of so of it.

The conclusions are that -

1 -*most* German infantry-type companies have 2x81mm, including armored, engineer, recon;

2 - many also try to have a 6x81mm battalion mortar section as well, mobile or leg though but not armored or engineer; but

3- there are not always enough for both roles, company and battalion, even of the 81mm; and next,

4- the 120mm is a rare bird compared to the quite-common 81s. Even the 81s aren't at TOE on any sort of uniform basis.

For what it is worth.