Calling all Nambu/Japanese experts...
 

I have seen a Nambu that has a mark "12 12".
Is this some kind of dating algorithm?

I know that the Japanese date some of their stuff according to the the "Koki" calendar.

For example, the A6M Type 0 IJN fighter is called such because it was accepted into service in the year 2600 of the "Koki" calendar.

The "Koki" calendar is based upon the ascendency of the first Japanese emperor in 660 BC which equates to year 1 of the "Koki" calendar.

They also used a dating system that was based upon the reign of a particular emperor. For example, Hirohito became emperor in 1926 and his reign was called "Showa". The dating system based upon the "Showa" calendar would be 1926 = year 1.

Very confusing, eh...

Anyway, even with all this info, I do not understand the "12 12"
marking on this Nambu. If anyone can shed light on this, that would be great.

Richard

I'm talking from distant past reaearch here, but that should refer to the number of years and months the gun was mfg. after the birth of the Emperor. Thus December of 1938.
Here is a great website on Nambu stuff. http://members.shaw.ca/tju/jhg.htm
dju

you take the date i.e. 12.12 and add 25 yrs plus the 12.12 date, so 1937 December

Ed and David,

Great information and detective work guys...thank you very much...don't you love a bit of a mystery.

thanks again,
Richard

In western world, year had religious origin, reference year 1 was Jesus Christ related. In the east, no religion had such a power, year 1 was the year current emperor became an emperor. Since reference points kept changing, there are many year 1, year 12, year 20, etc. Year number was unique only in the context of a single country, under the same ruler.

Showa year 12, was the 12th year of Showa Emperor became an emperor. 1945 was Showa Year 20.