Help translating data plate for a small optic sight

[beretta1934]

This is on a small boxed sight - can I get help with a translation of it?
Thanks

[GHP]

十三粍機用
Jusan miri Kijuu yo
13 mm machine gun use.

Machine gun is normally 機関銃 kikanjuu. I wonder if this 13mm is an auto/quickfire cannon?

— Guy

[GHP]

It might be for the Hotchkiss M1929 machinegun:
https://en.m.wikipedia.org/wiki/Hotc...29_machine_gun

In the section “Users” the Wiki article says the Japanese-licensed gun was called the Type 93 Machinegun.

— Guy

[beretta1934]

Thanks Guy. I think the Type 93 is the correct gun but this optical sight is likely only used in one of the multi-gun Hotchkiss mounts. It's hard to imagine anyone aiming at a moving target with such a small field of view

So below first are photos of the Japanese sight and wooden case with data plate. It looks almost unissued.

Next, are photos are the Hotchkiss design for a dual 13mm cannon (which the Japanese licensed both gun and dual mount design) but I think the IJN made some changes to the design of the slightly telescopic sight and its mounting method. Hard to know for sure but best I can guess given the lack of reference materials and any clear, detailed Japanese photographs.

There is so much more to the story and aiming of this gun then I want to go into but once the distance, speed and heading was dialed in the other large mechanism (to the right of the tele sight) the tele sight was actually angled to take all of this into account. As you can see in the bottom photo the sight is looking far to the right of where the gun barrels are pointing - in affect it is taking into account the actual lead required to hit a crossing airplane. This was ability to set that physical lead (thru the mechanism to the right of the scope) is actually referenced in the original US patent I researched for this mount design.

[hchris]

Just out of personal interest, what does it look like when you look through the optic? Is there some kind of reticle?

Would it be possible please to get some photos while looking through it?

[beretta1934]

Sorry but the actual sight is not in my possession. I was getting a translation ID the weapon usage. Item was up for auction and went for more than i was willing to go. My understanding was the reticle was a simple crosshair - all the lead calculations were handled by the mechanical ballistic computer