WI: Cruiser Ibuki (1943) cancelled in 1942 and resources reused for Type 100 SMG?

trurle

Banned
What if Japanese cruiser Ibuki will be cancelled together with new Yamato class battleships back in 1942, and freed resources used to produce submachine guns?

1) How much SMGs Japan is likely to have at the end of the war?
2) Likely last positions and date of the war? Both on Pacific theatre and in China.
3) Will Type 100/44 SMG (improved reliability) come faster, and if so, when?
4) How much increased number of Japanese SMGs will affect Japanese casualties?
5) Same about US and Chinese casualties?
6) Is Type 100 SMG going to make a difference during Soviet invasion to Manchuria?
7) Will Japanese be able to supply enough ammunition for Type 100 SMG?

https://en.wikipedia.org/wiki/Type_100_submachine_gun
https://en.wikipedia.org/wiki/Japanese_cruiser_Ibuki_(1943)
 

Delta Force

Banned
Warships and firearms require very different infrastructure. Proposals for canceling armored warships to build tanks are a bit more valid because both require large amounts of armored plate.
 

trurle

Banned
Warships and firearms require very different infrastructure. Proposals for canceling armored warships to build tanks are a bit more valid because both require large amounts of armored plate.
The Ibuki in 1942 was in early stages of construction. The most of its steel was likely not smelted yet. Therefore, by "resources" i mean mostly manpower and equivalent amount of raw materials (not necessary exactly the same materials used on Ibuki) rather than pre-fabricated parts. Tools and jigs for ships are incompatible between ships and SMGs of course, but it applies for any non-ship production (including tanks).
 
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Isn't it sort-of simpler to just convert some of the capacities used for Arisakas (or indeed, some other infantry weapons-not very knowledgeable on the matter though) to build these SMGs? If anything, probably not building some of the more useless light tanks would free enough steel for the SMGs.
 

trurle

Banned
Isn't it sort-of simpler to just convert some of the capacities used for Arisakas (or indeed, some other infantry weapons-not very knowledgeable on the matter though) to build these SMGs? If anything, probably not building some of the more useless light tanks would free enough steel for the SMGs.

Yes, it is the sort of things what can happen naturally. Resources will be exchanged across the country, likely across similar industries. But for the Arisaka rifle case, the Japan by 1945 run out of reserve of Arisakas (including older WWI-era models). To avoid complications of analysis of type "less Arisakas and more SMGs" i propose to use materials and manpower from Ibuki (which has exactly zero military utility IOTL). So analysis is simplified to case "more SMGs".
 
Well as far as materials are concerned, Ibuki was laid down in April 1942 so before that already a significant part of the materials would already be in the pipeline i would think (i.e. already manufactured).

Anyway, apart from the issue of the infrastructure needs for these SMGs, number of workers needed, rate of production etc. the other is really how much steel is used to make each one, so then one can estimate some figures. So we are looking at what, tens of thousands more SMGs, hundreds of thousands?

Of course, japanese troops will be well served if equiped with good numbers of semiautomatic rifles (as discussed in another topic) as well as a good numbers of SMGs. Again, just as an exercise on can try a rough estimate of the increased effectiveness by calculating how much firepwower a standard platoon or whatever has with Arisakas, then how much will that be increased with SARs, and the same with SMGs (obviously only a portion of troops will field these presumably), then calculate how many rounds per opponent hit were expended OTL (from the overall casualty figures due to all causes) and then try to guesstimate the figures with increased firepower/rate of fire.
 
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trurle

Banned
Well as far as materials are concerned, Ibuki was laid down in April 1942 so before that already a significant part of the materials would already be in the pipeline i would think (i.e. already manufactured).

Anyway, apart from the issue of the infrastructure needs for these SMGs, number of workers needed, rate of production etc. the other is really how much steel is used to make each one, so then one can estimate some figures. So we are looking at what, tens of thousands more SMGs, hundreds of thousands?

Of course, japanese troops will be well served if equiped with good numbers of semiautomatic rifles (as discussed in another topic) as well as a good numbers of SMGs. Again, just as an exercise on can try a rough estimate of the increased effectiveness by calculating how much firepwower a standard platoon or whatever has with Arisakas, then how much will that be increased with SARs, and the same with SMGs (obviously only a portion of troops will field these presumably), then calculate how many rounds per opponent hit were expended OTL (from the overall casualty figures due to all causes) and then try to guesstimate the figures with increased firepower/rate of fire.

I.m.h.o., the limiting resource was copper and zinc (and may be chromium), not the steel proper. To kill an opponent with SMG, one need approximately ~1000 cartridges in typical case (battle of Peleiu). It mean ~5kg brass (which is unlikely to be significantly recycled) and ~3kg of steel for SMG itself. Japan had copper production crippled in 1942 and collapsed by 1944.
http://www.24hgold.com/english/stat... copper production&pays=Japan&deid=34258B1670.
Do not know much about zinc, but situation must be even more dire than for copper, because zinc was used in main Japanese aluminium alloy 7075.
 
Historically the Japanese already had a decent number of submachine guns in their arsenal as it was, among a plethora of other light automatic weapons and mortars. Further emphasis on SMG production probably wouldn't have made much of a difference.
 

trurle

Banned
Historically the Japanese already had a decent number of submachine guns in their arsenal as it was, among a plethora of other light automatic weapons and mortars. Further emphasis on SMG production probably wouldn't have made much of a difference.
If you know the numbers of mass-produced Japanese SMGs, please write it. As i know, combined number of Japanese SMGs and LMGs was just about 100 thousands. For comparison, Soviet Union wartime production of PPSh and PPS SMGs was about 8 millions.
 
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If you know the numbers of mass-produced Japanese SMGs, please write it. As i know, combined number of Japanese SMGs and LMGs was just about 100 thousands. For comparison, Soviet Union wartime production of PPSh and PPS SMGs was about 8 millions.

The Japanese made relatively few (>50,000) SMGs domestically, but used large numbers of foreign built weapons, particularly the Solothurn MP-34. While I don't have exact numbers on deliveries made, this weapon was the most common SMG in Japanese service during World War II.

In terms of infantry machine guns, though, the Japanese made large numbers of these: 450,000 manufactured between 1939 and 1945, a total about half that of Germany and a third that of the USSR (Harrison, "The Economics of WWII," table 1-6). Part of the reason why emphasis on submachine guns was not so great was because prior to the Pacific War the IJA was designed to fight out in wide open or lightly wooded environments against the Soviet and Chinese armies and regarded their traditional compliment of artillery, mortars, and long range rifles sufficient: short-range machine pistols were unsuited to the projected battlefield. Nevertheless, they were present in appreciable quantity when needed. This paragraph excerpt from Ian Morrison describing the Malayan Campaign in "A Taste of Courage" is instructive:

"Nearly all the Japanese infantry were armed with tommy-guns or other light automatic weapons. They were ideal for this close-range jungle fighting. Our men were armed chiefly with rifles and the percentage of automatic weapons was small.

...

Many of our officers continued to swear by the rifle fight up to the end of the campaign, and there are sound arguments on both sides of the rifle-versus-tommy-gun controversy. But it always seemed to me that the rifle's chief use is as an accurate long-range weapon, and in Malaya there was rarely an extended field of fire. The advanced Japanese units would carry perhaps six or eight drums of ammunition with them and further supplies would be brought up...

After the tommy-gun the next most popular weapon with the enemy was a light 2-inch mortar. Again, it was a weapon ideally suited to jungle warfare. It was very mobile and was easily transported and operated by two men. It was very accurate. The shell burst with a loud report. There was also a 4-inch mortar, which was seen mounted on armoured carriers."

While it was clear that the IJA did not have as many submachine guns as say, the US Army or the RKKA, they were certainly there.
 

trurle

Banned
I checked the question about MP34 usage in Japan. Although reference
Foreign Military Weapons and Equipment, Vol. III, Infantry Weapons, Pamphlet No. 30-7-4, Department of the Army, 1954

has claimed "large amount" sold to Japan, it left a surprisingly small footprint in Japan.
Only commented photo i can find is here:
http://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1294037892
From discussion it is clear the MP34 was issued to IJA troops before Pacific War, but was a rare weapon.
Also photos,
http://bbs.tiexue.net/post2_11088801_1.html
Unreliable sources claims what total import numbers of MP18, MP28 and MP34 variants was 6000 units.
 
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I checked the question about MP34 usage in Japan. Although reference
Foreign Military Weapons and Equipment, Vol. III, Infantry Weapons, Pamphlet No. 30-7-4, Department of the Army, 1954

has claimed "large amount" sold to Japan, it left a surprisingly small footprint in Japan.
Only commented photo i can find is here:

There are other such photographs.

MP34:

tumblr_nnvvssoCEA1s57vgxo5_r1_500.jpg



Japanese1937.jpg


MP28:

JapaneseImperialMarines.jpg


AA+_59_4+0+0+0+0


Besides those, there is this War Department pamphlet on Japanese tactics in Malaya (http://www.lonesentry.com/manuals/malayan-front/index.html) which emphasizes their heavy usage of automatic weapons there.

- So far the Japanese have used mainly machine guns, submachine guns, mortars, and grenades, but not much artillery. They are, however, beginning to increase the use of artillery. Mortars and grenades especially have been very effective.

- Front-line troops are equipped with submachine guns and light machine guns, thus providing a volume of fire that seems to indicate heavier armament than that actually possessed.

- Japanese companies advance behind one and two-man patrols which are armed with submachine guns. When the patrols are fired upon, they do not stop, but maneuver around the flanks and infiltrate deep into the British position toward their objective, attempting to reduce any opposition met.
 

trurle

Banned
Seems reader so far were stuck with the pre-requisites of POD (more Japanese SMGs):confused:. But how about original question of the consequences of the POD?
 
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