Unknown IJN Arsenal Marks

[BOUGAINVILLE]

I have this IJN 76.2mm projectile dated March 1943 with the following marks on, and just above the drive band. The Arsenal anchor logo is one unknown to me as is the H in a diamond logo etc. I wonder if anybody can shed any light on these.


I might've thought that Hiratsuka would be a good candidate but that doesn't count for the logo having been found also on a hand full of IJN training rifles. The H in the diamond logo would certainly have Hiratsuka as a candidate. It is unusual that nobody has any information on Hiratsuka markings considering that it operated for about 40 years and started out as a joint venture between Armstrong Whitworth, Nobel and Vickers. The fact that Hiratsuka started out as a joint venture between the above western companies would make it very plausible for the H in the diamond marking. If this is so, then it might further strengthen Hiratsuka as a candidate for ownership of the anchor with the inverted V.

As far as I can find out Hiratsuka facilities consisted of seven plants:
Smokeless powder for rockets and artillery
Nitrocellulose and mixed acids production
Various acids and hydrogen production
Design and Engineering, prototype development
Machine gun ammunition production, solvent recovery
Naval artillery shells
Nitroglycerin production

Hiratsu...itions Arsenal - Wikipedia, the free encyclopedia

Sagami Naval Arsenal I don't have any information on besides that mustard gas was recently found buried on it's former site.

Hiratsuka Naval Ammunition Arsenal also would not be using Kana symbol for "Hi" as this was used as a filling mark by the Hiroshima Army Arsenal, it thus would've used a different Kana symbol. What Kana symbol is the question? Could it be "ナ" (na) and "コ" (ko)?

The naval arsenals that I have logos for are Tokokawa, Kure, Sasebo, Yokosuka and Maizuro. None of their anchor logos could be remotely mistaken for this unknown logo of an anchor with an inverted V. The closest is Yokosuka with an anchor with a V.

Cheers,
Robert

[ogreve]

Hiratsuka Naval Ammunition Arsenal also would not be using Kana symbol for "Hi" as this was used as a filling mark by the Hiroshima Army Arsenal, it thus would've used a different Kana symbol. What Kana symbol is the question? Could it be "ナ" (na) and "コ" (ko)?

Hiya Robert,

Good to see you here too!
As you know, I too was investigating the Hiratsuka arsenal and while doing so came across this post of your's.

I think I can at least semi 'answer' the part you ask about above. That particular marking does not seem to be specific to the Hiratsuka arsenal, and may not even be specific to any particular arsenal at all. If you consider the attached images of some of my Toyokawa manufactured Type 91 MT fuzes, you'll find that the leftmost one of these too has that same symbol in the circle, right to the left of the Toyokawa arsenal anchor. The rightmost one has the 'To' Katakana symbol, that ought to indicate 'Toyokawa'. Curious... Do you have positive confirmation that this symbol is a filler mark?

On another note: I am not too sure the IJN would not have used 'Hi' in order to prevent confusion with the Army arsenal: the IJA and IJN were extremely distinct entities, and they might not have taken such possible confusion with an Army arsenal into account. But... that is of course mere conjucture. For all I know, perhaps they did intentionally not use the 'Hi' designation...

Either way: I hope someone can shed a light on the anchor with inverted 'V'. According to Ken Elks' book on Japanese ammunition, the Kure arsenal made use of two styles of 'wavy' anchors, with the difference being the waves being inverted. In light of the Maizuru, Sasebo and Yokosuka arsenals basically having the first (Western) letter of the arsenal printed over the anchor, it is not so likely that the 'Y' of Yokosuka would ever be inverted, but who knows...

One more mystery (I don't have pictures of these yet, but I can make them) is the anchor that has a distinct 'H' over the anchor. I think many people confuse that one with the Maizuru arsenal. I have that anchor on some 4 large IJN casings (calibres of around 120+ mm). That one is a mystery too and *might* also be the Hiratsuka arsenal mark. It would at least make ALL the sense in the world to me.

As for the 'H' in the diamond shape.... Hang on for that one for a while. It is a marking that strikes me as very familiar. I shall check my IJN stuff, but I'm quite sure I've seen similar markings before. One of them is confirmed for sure, as can be seen in the attached image, being the letters 'TKS' on a 40x158R belt link. I would not be surprised if such a mark indicates e.g. the supplier of the steel. Much like I very strongly suspect the 'F' on Army cases to indicate the grade or manufacturer of the brass. The respective belt link carries the Kure arsenal anchor too, so I'm strongly suspecting these 'diamond' markings to actually not represent the arsenal, but something else, and that 'something' might well be a sub part of the arsenal, being the supplying steel factory or so.
And..., to further confuse (or not) matters: I've seen similar markings an some Army projectiles too, like an 'F' in a shield on an IJA 30x155 TP projectile. As these kinds of markings seem to only appear on projectiles, I'm strongly suspecting them to indicate "something" regarding the steel the projectiles are made of. My best bets are that that "something" is either the "supplier" or the "grade" (in terms of 'quality', instead of 'hardness', as the IJA at least used colour bands for indicating the differences in steel hardness).

I hope someone else can add to this.

Cheers mate,
Olafo