WP in CMAK

[Mr. Tittles]

A Military Encyclopedia

Based on Operations in the Italian Campaigns, 1943-1945.

[p. 527]

Chapter Thirteen

CHEMICAL

Section 1. The 4.2" Chemical Mortar

The 4.2" Chemical Mortar proved itself an invaluable weapon when used in direct support of Infantry

troops to neutralize enemy strong points and to lay smoke screens. Its greatest value lay in its accuracy and

the terrific mass of fire it could lay on a target in a short space of time. Initially, white phosphorus [WP]

shells were used only for spotting targets and smoke screening, but later they were also used very

effectively as incendiary and as harassing and casualty-producing agents to burn the enemy out of well dug-in

positions. The combined use of HE [High Explosive] and WP was most effective.

The matter of tactical control of the fire of Chemical Mortar units, a somewhat controversial subject,

was settled very early in Italy in favor of the supported Infantry. While at times it was advantageous to tie

the 4.2" mortar fire into the Artillery fire plan, such occasions were far outnumbered by the requirements for

quick and accurate fire at the call of the Infantry. The fewer the communication channels, and the fewer

persons authorized to make decisions as to delivery of desired fires, the better was the final result.

Practically without exception. Companies, and at times even Platoons were attached to RCTs [Regimental

Combat Teams] and operated as a part of the Infantry fighting team. A frequent variation was the mutual

planning of massed fires by 4.2" mortars attached to two or more RCTs on a single important target, but

always with the provision that the 4.2" mortar unit should revert upon completion of the fire mission to control

of the unit to which it was attached.

Due to the habitual shortage of Chemical Mortar Battalions, ideal tactical employment of the 4.2"

mortar was seldom passible, as the Mortar Battalions had to cover wide fronts for several Divisions

simultaneously. This being the case, individuals mortars were required to fire on separated targets, even

though it was realized that massed fire by platoon, company, or battalion were more destructive.

[p. 528]

This would have been obviated if a Chemical Mortar Battalion had been available to support each Infantry

Division.

The 4.2" mortar was only semi-mobile, and a roadnet into the mortar position was necessary for

maximum employment of the weapon. In a fast moving situation, displacement of the mortar to accompany

the foot troops was usually difficult, especially over rugged terrain. This weapon, normally transported by

mortar cart or in a jeep-towed 1/4 ton trailer, required as many as thirty mules per Mortar Platoon to maintain

an ammunition supply to some of the mountain gun positions.

[Mr. Tittles]

C. MORTAR PLATOON (FM 17-27). The mortar platoon is equipped with three 81-mm mortars mounted in half-track vehicles. The mortar may be fired from the vehicle or the ground. The platoon operates usually as a unit rather than as individual squads. The mission of the mortar platoon is to give close fire support to tank units with particular reference to destroying or neutralizing anti-tank guns. It operates directly under control of the battalion commander. As many of its missions will be screening, a preponderance of smoke ammunition is carried. Smoke is used as directed by the battalion commander and must not be allowed to interfere with the movement of the battalion or adjacent troops. The platoon normally moves with the battalion reserve and where it is readily available to the battalion commander.

[Mr. Tittles]

Some thoughts about 4.2", 81mm and 60mm WP mortars in Sicily/Italy.

60mm

I doubt that WP was used much with this weapon until late in the campaign in this region (North Africa, Siciliy, Italy). I also doubt it delivered much WP if it did. It would need a burster charge, like any other WP device, and WP radius might be 5 meters or so. In CM game terms, it would probably be no more than a small molotov cocktail in effect. It should pin troops close by, perhaps, or cause troops to displace slightly.

Its small smoke rounds should have a more immediate obscurant effect. There should be a very slight delay before the smoke appears. This is true for all WP generated smoke in my opinion.

81mm

Data shows that smoke rounds for this weapon (almost certainly using the WP filler) were not as abundant as the 4.2 inch mortar WP. They were stocked in dumps at about a 20-30 percent level of total though. The WP apparently used a larger shell than the HE light (preferred) round. It had greater overall weight. While this stymied its use as a marker round (evidence suggests it had the same size as a artillery WP round) it should have been an effective WP smoke/casualty-producing round. Evidence shows it to have been used with an incindiery effect. Armored Bns that used the 81mm halftracks should have a higher percentage of 81mm WP than most 81mm US mortars. I think that its effects of WP should not be ignored. Since the round is non-spinning (smoothbore), its WP would have to rely on the burster charge and violent reaction of the WP with air to distribute the WP. I would imagine that its WP plume would be less distributed and concentrated near the strike.

{side note: CM artillery rules for off-board use of mortars allows total flexibility as far as rounds being HE or smoke. This is ahistorical and needs addressing. Clearly this is impossible. Perhaps the game should limit smoke round capability to one full turn at most. Or just make a percentage level chance that smoke capability disappears.}

Also interesting is the shortage of rounds for the 81mm late in this theatre. Perhaps operations in France had priority. I have read that captured Italian 81mm ammunition was issued with cards showing how to fire them from US mortars. Rarity might take this into account. I have read of one battle where both 60mm and 81mm rounds were not available and 4.2" held the line.

4.2"

This weapon had an outstanding record and its effects, both HE and WP, are well documented (does anyone really want to challenge this?). It dropped 8 lbs of HE and its WP delivery was equally awesome. Whole villages were blown to pieces and burned to the ground. Its spin stabilized round was more akin to very high angle howitzer artillery. To not model the WP of this weapon is an oversight in a game such as CM. I would contend that its spinning WP round, on breaking up from the burster charge, would produce lethal splinters in addition to a very large radius of WP. The spinning also aided in the WP distribution radius. The radius may have been around 30m+ or so. Any unit withing 0-10 meters would be within a combined blast/fragment/heat/WP-cloud. Units within 10-20 meters would be under a rain of WP particles and fragments. Units within 20-30 meters would be driven away or forced under cover. Since the round landed at a very steep angle, this radius would be more circular like a typical fragmentation distribution from a mortor round is.

[ October 24, 2003, 12:42 PM: Message edited by: Mr. Tittles ]

[Determinant]

Originally posted by Mr. Tittles:

I would contend that its spinning WP round, on breaking up from the burster charge, would produce lethal splinters in addition to a very large radius of WP. The spinning also aided in the WP distribution radius.

Speaking as a believer. And WILLUY PETRRE has made me a believer how do you calculate the added advantage that spin gives to lethality as opposed to accuracy?

As Sam Cooke so memorably sung I don't know a lot of mathematics; don't know about the science books I took etc...

But I can't see that there is any lethality advantage to be gained by spin. Looking at it in geometry terms 2.1 inches (for a 4.2 in bomb) is not very much leverage - even if it is spinning like a dervish. Dwarfed I would have thought by the forward velocity of the bomb. And - It's the BURRSHTIN' CHARGE ladee!

Dunno... Anyone do hard sums?

[Mr. Tittles]

The advantage of spin is two fold in the case of the 4.2 inch WP.

1. The spin will distribute the WP once the shell case is broken/shattered. The WP itself is flung out centrifically in addition to be burshted out. the burster is centrally located down the center of the shell and surrounded by the WP.

2. The shell casing fragments are also given a velocity from the spin. This velocity component would be added to the velocity from forward motion of the shells flight and the burster charge kicking them out.

So the spin would both aid the accuracy and the effect of the payload. Think of it this way; If the incremental repeatable change in correction of where the round lands is less than the circular radius of lethality, then a mighty good thing is happening.

To be honest, I do not know the rifling/spin rate but in guns like the sherman 75mm I have heard 20,000 RPM. An interesting thing is that the different sized particles/fragments would all get the same velocity vector from the spinning if they are all equally distant from the axis of rotation.

I guarantee you that any sized piece of metal that WAS spinning at 10,000-20,000 RPM at 2.1 inches that strikes you would be memorable. Add in the forward velocity vector and burster kick and it would ruin your day/life. I have a feeling that the burster charge in a WP shell makes much larger sized fragments than a fully loaded HE shell would (given the same shell).

[ October 24, 2003, 09:56 PM: Message edited by: Mr. Tittles ]

[Mr. Tittles]

Germans had WP tank shells?

http://www.bbc.co.uk/history/war/wwtwo/battle_arnhem_04.shtml

So near yet so far

On 18 September, the second day, XXX corps began to make the progress expected of them. Their tanks covered 20 miles in a few hours, hooking up with the Americans at one of the intact bridges near Grave. On the third day they reached Nijmegen, where the Americans were still fighting in the streets in their efforts to reach the bridge across the might River Waal.

Once they had taken Nijmegen bridge, only Arnhem would be left, and the north end at least was still in British hands. It seemed that Operation Market Garden might succeed.

But they could not get across the bridge. General Horrocks, XXX corps commander, ordered American troops to attack across the River Waal, so that they could capture the German end. The attack was enormously costly.

'The bullets hitting the water looked like a hailstorm, kicking up little spouts of water. When we reached about the halfway point, then the mortar and artillery fire started falling. And when a boat was hit with an artillery shell or a mortar shell, it just disintegrated, and everybody was lost.' (Moffat Burriss)

Half of Burriss's company was killed or wounded on the crossing. The survivors reached the far bank, and from there successfully stormed the Nijmegen bridge. At last the route to Arnhem was in Allied hands. However, it was too late for the British parachute battalion at the north end of the bridge. The Germans had moved their tanks into the town, and one by one they were demolishing the houses in which the British were fighting.

By now the paratroops had few anti-tank weapons, they had no food, and, crucially, they had little ammunition left. Major Tony Hibbert remembers the German tanks were now devastatingly effective.

'We really had nothing we could do to them, and they drove up and down the street, firing high explosive into the side of the building, to create the gap, and then firing smoke shells through that. The phosphorus from the smoke shells burned us out. By about 8 o'clock, on Wednesday evening, the fires got out of control and of course we had by this time about 300 wounded in the cellars.'

The Allied troops were forced to abandon their positions near the bridge, and to try and fight their way out. Three miles from Arnhem British paratroops were holding a pocket of land at the village of Oosterberck. By now XXX corps, commanded by General Horrocks, was on the other side of the river from the airborne troops. They could not, however, cross.

German artillery controlled the river. Horrocks decided to evacuate the British survivors; only some 2,500 eventually made the crossing. The Parachute division had left behind nearly 1,500 dead, and more than 6,500 prisoners, many badly wounded.

Operation Market Garden had failed. It would be another four months before the Allies crossed the Rhine again and captured the German industrial heartland. The war dragged on, costing the lives of many thousands of civilians and servicemen.

[John D Salt]

Originally posted by Mr. Tittles:

http://www.rt66.com/~korteng/SmallArms/60mm19.htm

This site claims a 11 meter WP casualty radius. [snips]

Unfortunately, the site gives no comparable figure for the "casualty radius", however defined, of the HE bomb.

Looking at British WW2 mortars, it seems to me that the effectiveness of WP is in general rather less than HE against people in the open, and substantially more against people in slit trenches. Overhead cover would, I think, unless remarkably fragile and inflammable, reduce the effectiveness of WP to nil.

My reasoning and sources as as follows -- non-grogs please change channels now.

PRO document WO 291/150, "WP as an anti-personnel weapon", gives the following "incendiary areas", in square feet (about eleven to the sqaure metre), representing the area in which target personnel stand a 50% chance of becoming a casualty, in the open in hard, soft or marshy terrain, and in slit trenches in hard or soft terrain.

<pre>

Hard Soft Marshy Hard slit Soft slit

77 grenade 800

2-in mor 700

3-in mor 2700 1800 550 1500

4.2-in mor 5000 3000

</pre>

These numbers suggest (though it is not stated in the report) that the following multipliers have been used for the different terrain types:

<pre>

Terrain type Hard Soft Marshy Hard slit Soft slit

Multiplier x1.0 x0.66 x0.20 x0.55 x0.4

</pre>

This enables us to speculatively fill in the gaps (speculative entries in parentheses):

<pre>

Hard Soft Marshy Hard slit Soft slit

77 grenade 800 (525) (150) (450) (325)

2-in mor 700 (450) (150) (375) (275)

3-in mor 2700 1800 550 1500 (1075)

4.2-in mor (7500) 5000 (1500) (4100) 3000

</pre>

For comparison with HE vulnerable areas, defined analogously to the "incendiary area" above, we turn to PRO document WO 291/579 "Comparison of mortar bombs". This shows:

<pre>

2-in mor 1200

3-in steel 5000

3-in cast iron 6500

</pre>

A terrain masking factor of 1.5 has already taken into account in calculating these, meaning that irregularities in the ground catch one-third of fragments that would otherwise be effective. These figures are higher than the most favourable ones given for WP.

WP is, however, more effective against targets in slit trenches, as the WP particles lose velocity rapidly and descend near-vertically. WO 291/150 states that if four 3-in mortars fire 100 HE bombs into an area 100 yards square occupied by a platoon (48 men) in slit trenches, it is considered that there is a 60% chance of destroying one trench (4% of the platoon). The same number of WP bombs is expected to result in 40% casualties.

All the best,

John.

[Edited to try to get the tables aligned properly]

[ October 25, 2003, 09:54 AM: Message edited by: John D Salt ]

[CombinedArms]

Mr. Tittles deserves a Nobel War Prize for his research into the use of WP ammo. I for one am now quite convinced that it was used very extensively by US forces in Italy and to great effect. Also, that the Germans feared this weapon and didn't really have an equivalent. I wonder if BFC could comment on the possiblity of including WP in CMAK, if not in a first release, then perhaps in a later update?

[Mr. Tittles]

This Battalion fired a half million rounds?

http://www.4point2.org/hist-83.htm

Conclusion

The end of the war in the European Theatre brought to a close a brilliant combat record. The unit had served 508 days in combat. The Bn has participated in the initial assaults of 5 amphibious operations and one airborne operation and has fought in six campaigns. As one of the old combat units in the war in Europe, the 83d fought through hot, malaria-infested Sicily, through the heart-breaking fighting on the forgotten mountains of Italy. The Bn went through the hell of Anzio, then there were the cold dismal days in the Vosges, this was followed by the difficult combat in the Colmar and Hagenau sector which represented the final serious struggle of the enemy. Finally, the Bn drove through the Siegfried line, crossed the Rhine, and took part in the complete destruction of the enemy forces. The Bn ended its combat by making contact with the Fifth Army at Brenner Pass.

During its combat history, the 83d has worked with many excellent units. There were the never to be forgotten Rangers, the 1st, 3rd and 4th Bns and the 2nd and 41st British Commandos. The Bn worked with the 82nd and 101st Airborne Divs., as well as with the following separate parachute units, 509th, 517th and the 550th. The 83rd has been teamed with the old 1st and 2nd Armored Divs. as well as the newer 10th, 12th and 14th Armored Divs. The 83d has been attached to the following infantry Divs: 1, 3, 9, 34, 36, 42, 44, 45, 63, 71, 79, 85, 88, 100, 103. Along with the 36th Combat Engrs., and the 117th Cavalry, the 83d has held the line on many occasions. The 83d has also been a member of a number of special task forces.

During the months of combat, the Bn expended just short of one half million rounds of ammunition, almost 5,000 Italians and Germans had been captured and 230 allied prisoners were liberated by the men of the 83d. For distinguished service, the following awards have been given:

[Mr. Tittles]

Interesting information John. I will crunch some numbers when I get a chance.

Perhaps WP is in CMAK? It is eerily quiet from both Battlefront and people that have seen the game.

If it isnt in CMAK, how difficult would it be to include? I think that infantry WP grenades could be modeled as molotov cocktails that burn for a minute and perhaps give off dust/smoke. Mortor rounds (81mm and 4.2") should generate instant smoke on landing and could have some Blast equivelence. They could also have a greater tendency to start fires when applicable. The same could be true for 105mm and other rifled-tube artillery. If nothing else, it should be modeled as quick acting smoke. This would not require that great an engine rewrite I would guess.

I am still researching direct fire WP rounds. Principally the sherman 75mm. If anyone knows of other use of WP please post it if you would.

[Mr. Tittles]

Berger's Mixture

Supposedly the germans used this concoction. Anyone know how nasty it is?

http://www.mitretek.org/home.nsf/environmentenergy/FlameandSmokeMunitions

Actually, most military smoke in confined places makes for bad breathing.. I would guess that the British soldier was just mistaken and assumed he was being fired on by WP but it was just some noxious gas from the above mentioned sites. But you never know. I ran into one site that claims that Germans used WP in small AA or air cannon rounds.

http://www.nbc-med.org/SiteContent/MedRef/OnlineRef/FieldManuals/fm8_285/PART_2/chapter8.htm

[ October 25, 2003, 01:27 PM: Message edited by: Mr. Tittles ]

[Michael Emrys]

Originally posted by Mr. Tittles:

Perhaps WP is in CMAK?

Not meaning to rain on your parade, but I wouldn't get my hopes up. CMAK is being something of a rush job with minimal alterations to the game engine at this point. I think adding WP in a satisfying way will involve more research and coding than you are thinking of.

For one thing, the availability would have to be controlled in some kind of realistic fashion or it will simply be used in a gamey way. To this point, we haven't yet estabished what the level of usage was among the different armies at different times and in the various calibers. Your numbers suggest that from late '44 on it was plentifully supplied to the 4.2" battalions, and may have been present in the 81mm platoons as well. But I've never heard much about it being fired from 105mm cannon and nothing at all in larger calibers in WW II. It may have been used, but it's not obvious that it was a big item.

Here's my thinking: The whole artillery model is due for a major revision in CMx2 and it will be easier to account for various kinds of ammo at that time. For one thing, in the existing system, I think it is far to facile for a player to switch from smoke to HE and back again on the spur of the moment, as it were. A normal unit of fire for a battery was mostly HE and a little smoke. For special pre-planned missions, that ratio could be changed though. So to account for that, when a player buys an artillery module, he specifies what kind of ammo and in what proportions. Different kinds might cost more points depending on their availability in the theater. Once the player has established the ratios at the start, that's what he has to play with. Once the game starts, he can't just decide to go with all smoke or all HE the way he can now.

Once that's done, WP can be fit right into the system.

Michael

[Mr. Tittles]

'Late '44'?

Thats incorrect about the 4.2 inch WP. In fact, the WP shell was developed and fielded before the HE! From Sicily onwards, WP has been shown to be a major projectile system for the 4.2". I do not see how that has not been shown.

I have other documents that show that WP 75mm howitzer rounds were present before smoke shells were developed for them. This projectile may be the same as the sherman 75mm.

[Mr. Tittles]

Note: sherman 75mm used M64 WP shell and 105mm used M60 WP shell. This is only one plant but I would safely assume that 1943 was a production year for WP 75mm and 105mm. These may have been produced sooner at another plant.

http://www.redstone.army.mil/history/studies/xi.html

Production proceeded on the 105-mm M60 white phosphorus (WP) or mustard gas (HS) shells, the 155-mm WP or HS-filled shell, M5 and M6 burster charges, the 100-pound A1 WP bomb, and the 100-pound A47A2 HS bomb. Among the new orders received in 1943 were those for M8 burster charges (by the casting method); M4 and M10 burster charges; 115-pound M70 HS bombs; 75-mm WP M64 shells; and 105-mm M84 HC base ejection shells.

The equipment on Line No. 3 had to be altered slightly to manufacture the M64 shell. Although few problems were encountered in making or assembling the shell, proof-firing indicated that it was improperly designed or needed different components. The trouble was traced to the M8 burster, which was not powerful enough to detonate the shell properly. Since a reconsolidating pure tetryl burster was deemed more effective, the Chief of Ordnance decided in May 1943 that cast bursters would no longer be used and that Redstone would go into production of the new bursters immediately at the rate of 250,000 a month. Six reconsolidating machines were put into operation but never worked properly. Three could have done the job if they had been perfected. Production schedules were met, but only because twice the number of people ordinarily used were assigned to the work.

[Mr. Tittles]

The lack of empty shells soon caused a serious reduction in schedules. This was not the fault of Redstone; it was rather a matter of having production schedules set higher than the availability of empty shells. Such a shortage in April 1942 stopped the assembly of mustard gas rounds, but the shift to the manufacture of white phosphorus shells ran smoothly.

also..

New production in early 1944 included the 75-mm M89 base ejection shell; the M104 and M110 155-mm shells, both having either white phosphorus or mustard gas filling; the 81-mm M57 white phosphorus mortar shells; and the M13 burster. Increased demands for M1 demolition blocks necessitated a redesign and relocation of equipment and fixtures on Line 2 in order to produce 1.5 million pounds of such blocks a month.

Expansion Completed

The mechanization and expansion programs begun in 1944 were essentially complete by V-J Day. They included the following. Line 1 gained four buildings and the necessary facilities and utilities; namely, one melt-pour building, two screening and storage buildings, and one change house, to produce 200,000 pounds of tetrytol bursters per month. Additions to Line 2 included three buildings, plus facilities and utilities, to increase the capacity of this line to 3,000,000 pounds of tetrytol demolition blocks per month. One of the two new buildings constructed in Line 3 was for processing ammunition returned from overseas. The other was a paint storage building. These, plus extensive renovation of existing buildings to adapt the line to mechanized assembly of 105-mm chemical shells, would enable the line to produce 625,000, instead of 235,000, rounds per month. Likewise, a new paint storage building and additions to existing buildings at Line 4 would permit production of 650,000 rounds of 81-mm chemical mortar shells per month. Changes to Line 5 and the addition of a storage building more than tripled the production capacity for 155-mm chemical shells from 58,000 to 190,000 projectiles per month.

From the website above. I think it is clear that 75mm, 105mm and 155mm WP shells were produced. 81mm were produced at great rates also. as I said, there may have been other factories or existing stocks of WP previous to these numbers.

[ October 25, 2003, 02:01 PM: Message edited by: Mr. Tittles ]

[John D Salt]

Originally posted by Mr. Tittles:

If it isnt in CMAK, how difficult would it be to include? I think that infantry WP grenades could be modeled as molotov cocktails that burn for a minute and perhaps give off dust/smoke. Mortor rounds (81mm and 4.2") should generate instant smoke on landing and could have some Blast equivelence. They could also have a greater tendency to start fires when applicable.

Without knowing how the innards of the game work, one migfht speculate that a programming difficulty would be showing the different effects of different ammunition natures depending on the terrain occupied by the target. HE fuzed superquick is certainly more effective on hard ground than in soft, but the exact protection factors applied should probably be different for each nature/type combination. In particular, slit trenches should be mush less effective against WP than aginst HE superquick.

Originally posted by Mr. Tittles:

The same could be true for 105mm and other rifled-tube artillery. If nothing else, it should be modeled as quick acting smoke. This would not require that great an engine rewrite I would guess.

It would be nice if the modelling of smoke could ultimately show the difference between WP bursting smoke, pumice/oleum or chemical bursting smoke, and base-ejection smoke.

Looking through a couple of Ian Hogg's books shows the following natures of smoke shell to have been available for British, American and german WW2 artillery:

"British & American Artillery of World War 2", Ian Hogg, A&AP, London, 1978.

18 pdr gun -- WP bursting smoke

25 pdr gun how -- BES (4), BE TI and an incendiary (thermite) round. WP developed but not issued

3.7" mtn how -- WP bursting smoke

95mm how -- BES (3), BE TI

4.5" how -- WP bursting smoke and BES

4.5" gun -- no smoke

60 pdr gun -- no smoke listed

5.5" gun -- BES (4) "rarely issued", BE TI probably never

6" 26 cwt how -- no smoke listed

6" gun -- no smoke listed

7.2" how -- no smoke

8" how -- no smoke listed

9.2" how -- no smoke listed

12" how -- no smoke listed

75mm pack how -- WP bursting smoke, FS bursting smoke (titanium tetrachloride)

75mm gun -- WP bursting smoke

105mm how -- WP bursting smoke, FS bursting smoke, BES (3) HC

4.5" gun -- no smoke

155mm how M1917, M1918 -- WP bursting smoke, FS bursting smoke (sulphur trioxide), BES (3)

155mm how M1 -- WP bursting smoke, FS (titanium tetrachloride) bursting smoke, BES (4)

155mm gun -- WP bursting smoke, FS (titanium tetrachloride) bursting smoke

8" how -- no smoke listed

8" gun -- no smoke listed

240mm how -- no smoke listed

57mm RR -- no smoke listed

75mm RR -- WP bursting smoke

3-in anti-tank gun -- trailing smoke HC (hexachlorethane/zinc)

"German Artillery of World War 2", Ian Hogg, A&AP, London, 1975.

7.5cm leIG -- TI bursting smoke (blue)

15cm SIG -- no smoke listed

7.5 cm GebK 15 -- no smoke listed

7.5cm GebK 36 -- dyed HE

10.5cm GebH -- TI smoke

7.5cm FK 16 na -- no smoke listed

7.5cm leFK 18 -- pumice/oleum bursting smoke

7.5cm FK 38 -- no smoke listed

7.5cm FK 7M85 -- pumice/oleum bursting smoke

10.5cm leFH -- pumice/oleum bursting smoke, TI sugar/dye bursting smoke (blue), BES(1)

10cm K 17 -- no smoke listed

10.5cm leK 41 -- no smoke listed

10cm sK -- pumice/oleum bursting smoke

15cm s FH -- pumice/oleum bursting smoke

12.8cm K -- no smoke listed

15cm K -- no smoke listed

17cm K -- no smoke listed

Lg 21cm Mrs -- no smoke listed

21cm Mrs -- no smoke listed

21cm K -- no smoke listed

24cm H 39 -- no smoke listed

24cm K -- no smoke listed

28cm H -- no smoke listed

35.5cm H M1 -- no smoke listed

42cm Gamma H -- no smoke listed

BES (n) = base-ejection smoke, number of smoke candles shown in parentheses

BE TI = base ejection target indicating

TI = target indicating (coloured smoke)

Several things seem worthy of note. First, the Western allies appear to have a substantial edge on the Germans in smoke-making ammunition. Almost all German smoke rounds are bursting smoke using a pumice/oleum mixture, which I doubt is effective as the chemical compounds used in Anglo-American BES and some bursting smokes. The only German BES shell mentioned uses only one candle, and they seem to have issued no WP.

Smoke rounds are not issued for anti-tank guns of any nationality except the US 3-inch gun, and this is an unusual type which generates smoke in flight. It was apparently intended for use on SP equipments.

As far as artillery is concerned, smoke rounds seem to have been almost exclusively the province of the field artillery; the 5.5" smoke rounds saw little service, and only the Americans seem to have produced smoke for medium and heavy pieces.

I have not been able to guess exactly why Hogg refers to FS as being filled with sulphur trioxide in one case and titanium tetrachloride in others.

Finally, if AH's "Patton's Best" game is to be trusted, the 75mm gun as mounted in the Sherman should also have an HC bursting smoke round. The usual American practice seems to have been , very sensibly, to design a single pattern of bursting carrier shell capable of being filled with WP, a smoke compound or a chemical warfare agent.

Who's got smoke round information for Soviet artillery? Italian? Japanese? French? Anyone else?

All the best,

John.

[Mr. Tittles]

Has the artillery system been the same for both games? I think I read that the only major difference is the fixed type FO. But is everything the same as I see in CMBB? Is there to be no improvement in CMAK as far as the arty system?

I dont want the therad to take this side issue but I am just curios if someone could answer.

[Mr. Tittles]

THE UNITED STATES ARMY IN WORLD WAR II

by Rich Anderson

Chemical Weapons

The 4.2" mortar battalions provided chemical warfare (WP, smoke, and gas) support to Army divisions. Originally without an HE capability, inasmuch as there were no HE rounds for the 4.2" mortar, in late 1942 a bright CW officer thought that it would be a good idea to provide an HE round for the piece. As a result the chemical mortars were available to provide welcome heavy mortar support for the infantry by 1943. By the fall of 1944 there were sufficient battalions in the ETO to allow for a normal assignment of one company per infantry division. In some circumstances this would be augmented to a full battalion.

The 2nd, 3rd, 81st, 83rd, 86th, 87th, 89th, 90th, 91st, 92nd, 93rd, 94th, 95th, 96th, 97th, and 99th Battalions served in the ETO. The 84th and 100th Battalions served in Italy. The 71st, 80th, 82nd, 85th, 88th, and 98th Battalions served in the PTO.

http://www.militaryhistoryonline.com/wwii/usarmy/artillery.aspx

[Pzman]

Originally posted by Mr. Tittles:

Has the artillery system been the same for both games? I think I read that the only major difference is the fixed type FO. But is everything the same as I see in CMBB? Is there to be no improvement in CMAK as far as the arty system?

I dont want the therad to take this side issue but I am just curios if someone could answer.

There were a number of changes to the artillery system, I believe they are on the list of things changed in CMBB that is posted on the site.

http://www.battlefront.com/products/cmbb/new%20features.html

[ October 25, 2003, 06:16 PM: Message edited by: Panzerman ]

[Mr. Tittles]

Gains were now measured by two or three hedgerows an hour instead of two or three per day, but the hedgerows were becoming fewer and smaller. On the 27th of July, A Company entered St. Jean Des Baisants, a town utterly destroyed by artillery and mortar shells. Leaving by a sunken road which had been a previous target for the company, it came upon the body of a dead German. Beside him lay the base of an exploded WP shell, fired at a range of 4,200 yards. The instrument corporal was ordered to remove this road block since the accuracy of his calculations was held responsible for it. It was here that General Hayes, Artillery General of the 2nd Division, remarked on the accuracy of the 4.2s, as he had observed the first round of adjustment hit the rump of a horse; the target having been a convoy of horse-drawn wagons.

The major point here is that the WP shells would break into many fragments in that just the back piece was found. This is vital information for my next challenge; the direct fired gun/howitzer WP shell. The burster charge would not just fracture the shell body open but actually shatter it.

The advance continued. The Vire River was crossed. It was here that the infantry reported to C Company that the bursting WP shells had sent hundreds of Germans screaming into the river to ease their burning flesh where particles of flaming phosphorous had struck them.

[ October 26, 2003, 12:01 AM: Message edited by: Mr. Tittles ]

[Mr. Tittles]

Ammunition expenditure

The following is a recapitulation of ammunition expenditure from 6 June 1944 to 8 May 1945, inclusive:

unit---------HE--------WP------FS-----Total

Company A 30,685---17,335 -------- 48,020

Company B 30,011---33,615 -------- 63,626

Company C 36,889---23,329 --367--- 60,585

Company D 19,509---30,832 ----------40,341

Grand Totals 117,094 95,111 --367 -------212,572

Christ its hard putting data here.

The point is that FS is a very limited chemical shell

[ October 25, 2003, 09:32 PM: Message edited by: Mr. Tittles ]

[Mr. Tittles]

I am going to leave 4.2 " and other indirect arty fire for the moment to delve into direct fire WP rounds fired by weapons like the Sherman 75mm and 105mm weapons like the Sherman 105mm and Priest.

My contention is that these rifled weapons fired WP projectiles in trajectories closely parallel to the ground when firing in the direct fire mode.

As we have seen with 4.2 inch rifled rounds, the shells break up under the effects of burster charges so to render the sides of the shells into separate pieces (fragments).

The spin imparted to these rounds would then be imparted into the fragments as velocity driven projectiles. Not just from the spin of the shell (very considerable in the case of rifled guns/howitzers) but also from the burster charge and forward velocity of the shell. I am under no assumption that they would compare with regular HE shell fragments but actually had a unique benefit that I will try to explain.

I have given the case of 4.2" WP fragmentation some deep thought and would put my position as follows:

1. ground burst would limit frag damage from WP but enhance heat/blast/WP-splash against entrenched/building targets.

2. air burst would enhance frag damage but it would be directed downward in a cone fashion. Heat/blast would still be considerable for targets directly underneath and the rain of WP particles would be also be enhanced. An umbrella of hell would descend.

WP particles would be a horrible thing to be around POL supplies. They would also be very bad for exposed ammunition. If they landed on fixed ammo like ATG shells, and they generated such great heat on metal case surfaces, could the gunpowder be set off?

Another problem is vehicle radiators and other assorted engine bay mechanisms/systems. What happens when a bit of burning WP gets in a engine bay? If it were to be sucked in the cooling system and land aginst a radiator fanned as it is? Would it burn through the radiator?

[Mr. Tittles]

Finally, if AH's "Patton's Best" game is to be trusted, the 75mm gun as mounted in the Sherman should also have an HC bursting smoke round. The usual American practice seems to have been , very sensibly, to design a single pattern of bursting carrier shell capable of being filled with WP, a smoke compound or a chemical warfare agent.

Who's got smoke round information for Soviet artillery? Italian? Japanese? French? Anyone else?

[/QB]

I believe sherman 75mm should be WP. Also the Japanese used WP.

[John D Salt]

A couple of quick one-liners...

Originally posted by Mr. Tittles:

I believe sherman 75mm should be WP.

The same range of projectiles was used in the M1898, M1916, M2 and M3 75mm guns, and Hogg lists bursting WP for them, but not bursting HC. The AH game "Patton's Best" includes both, and this seems reasonable to me, as it is merely a question of changing the filler.

A trick to get the columns of your tables to line up when posting is to use the

<pre>

pre

/pre

</pre>

HTML tags (put angle brackets round them).

All the best,

John.

[ October 26, 2003, 05:34 AM: Message edited by: John D Salt ]

[flamingknives]

Curiously, the "Catalogue of Standard Ordnance Items, 1944, second edition" does not list a smoke shell as standard issue for the M3 (tank) gun.

It lists only M61 (APCBC shell), M48 (HE Shell) and M66A1 (hollow charge shell).

That being said, there are also a number of round listed as being usable for the M3 (tank) gun not listed in the gun entry. These include the M64 chemical shell (can be filled with WP) and also the M89, which is a base bleed smoke shell which is similar to the 76mm smoke shell