Japanese Type 30 Tokyo/Kokura Arsenal WWI? Bayonet

[gabbatemarco]

Hi, I just acquired this Bayonet. From my research I have found that is was made by either Tokyo or Kokura Arsenal. I have had a hard time find a year of manufacture. Does anyone have any information on this? Also, how can I tell if it was made by Tokyo or Kokura? Any help would be greatly appreciated. Thank you in advance.

Here are the photos:
Picasa Web Albums - Estate - Bayonet

[partisan42]

I have read conflicting dates on the Tokyo Arsenal to Kokura switch over. Honneycutt's book states Tokyo Arsenal up to 1936, Kokura Arsenal from 1936-1945. I have also read that it was Tokyo Arsenal up to 1923, Kokura from 1924 to 1937, Kokura subcontractors from 1937 to 1943 and finally Tokyo Arsenal again from 1944 to 1945.

I think the series mark before the serial number on the bayonet's pommel will help you to date it. The mark appears to be for the 31st series. I do not know what time frame this corresponds to. Also, the inspector mark beneath the Arsenal mark might help too.

[gabbatemarco]

Thanks!