8mm Nambu headstamp

Here’s a picture I received last night, and the details… “It is an 8mm Nambu shell made by Asahi Seiki in 1961 for the Japanese Coast Guard, which used Type 14 pistols after the war. The Asahi Seiki shell is very scarce, as they only made about 4,000 to 5,000 rounds a year and the Japanese forces are quite strict about policing up and disposing of brass.”


Photo credit: Teri Bryant

Thaks for sharing, Teri.


Japanese post-war pistol cartridges are all very scarce outside of Japan, due to their strict laws in Japan, as well as factors in their post-War Constitution, mostly written by the MacArthur Government of Occupation, prohibiting the exportation of military ammuniion from Japan.

Asahi-Okuma Arms Company, Ltd. was the name of the company until 1961, after which it became Asahi-Seiki Manufacturing Co., Ltd. The initials “AOA” were used alone on commercial ammunition, and in conjunction with the letter “J” for ammunition made for the Japanese Defense Force (JDF) and the Japanese Maritime Agency. “J-AOA” is the only headstamp so far seen on the 8 mm Nambu ammunition made in Japan in the Post-war period. Dates from 1960 to 1964 are known. After 1964, the Japanese Maritime Agency switched handgun calibers to .38 Special.

There is also a post-WWII Japanese-made 8 mm Nambu dummy cartridge, which looks somewhat like the wartime dummies. However, construction is totally different. The case and bullet are one-piece solid brass, with a large, mock copper primer set into the base, probably as a firing-pin striking surface, since the Type 14 Nambu has a somewhat fragile firing pin, easily broken by excessive dry firing on a empty chamber. This was recognized straight on by the Japanese after its adoption in 1925 (14th Year of Taisho). Type 14’s were issued with a spare firing pin carried in a little pocket on the face of the holster. The dummies have a knurled ring around the base of the cartridge, a smooth ring around the mock bullet, and two holes drilled through the cartridge at 2 heights, giving the impression of 4 holes in the “case.”

The ball rounds have a nickel primer with red seal, as shown in the headstamp picture previously supplied on this thread, and are with cases made of brass. The bullet has a GM jacket, lead core, and is FMJ RN, with a weight around 100 grains +/-. We have chosen not to pull the bullet on ours to check the actual weight, so that is approximate.

Pictures of the ball round in profile, and two minor variations of the dummy will be posted later.

Thank you, John for the additional information. That really completes the picture.

Teri also provided the following details: “The person I got it from gave me copies of pages from a 1996 book with the English title “Cartridge Headstamp Identification” (Japanese title Saikin no gaikokusei jippo miwakekata). Page 80 of this book identifies the maker of ammo with this headstamp as Asahi Seiki KK’s factory in Owari-asahi, Aichi prefecture (this is a suburb to the northeast of Nagoya). A 10 year history (junen-shi) of the Japanese Coast Guard (kaijo hoancho) indicates that the Coast Guard received a total of 5,000 war surplus Type 14 pistols in two batches after the war, of which 3,728 were still in inventory in 1960. Japanese Military Cartridge Handguns 1893-1945 by Harry Derby III and Jim Brown states on page 302 that 4,000 to 5,000 rounds per year of this ammo were produced between 1960 and 1963 and that they had copper- jacketed bullets. It is interesting that this amounts to only about one round per gun per year. After 1963 the Type 14s were withdrawn from service. I was told verbally that they were destroyed in the 1970s. The primer is of the Boxer type.”

For those that don’t know Teri, she is one of the leading Canadian experts on Japanese ammunition/small arms weapons and related materials. She teaches at the University of Calgary (Strategy and Global Management) and speaks Japanese. Her displays at local gunshows are always winners. Her website is members.shaw.ca/tju/jhg.htm


Makes one wonder what happened to the 1272 missing Type 14s prior to 1960. Could some leftover stocks of 8mm Nambu ammunition been used by the JCG in the early days (at least that which escaped being dumped into Tokyo Bay by MacArthur)? Does any pre-1946 8mm Nambu ball ammunition have headstamps? I have only a few rounds, and all are without any HS.

I well remember the days when a good Type 14 could be easily had for $20. This weekend I saw one that looked to have been buried in the Sands of Iwo Jima for the last 67 years - and the seller wanted $500 for it.

The only Japanese-made pre-1946 8 mm Nambu rounds I have seen that are headstamped are blanks, usually found with a red wood bullet, although I am told that plain wood bulleted blanks are also found. Mine has a curved line with one tick mark above it. The few others I have seen all had two. I was told “on authority” that mine just had one of the two marks run off the head of the cartridge due to poor stamping, but the source had never seen my cartridge, and it simply is not the case. I don’t know the exact meaning of these marks.

By the way, the ball rounds were made in Japan for at least 41 years, and aside from the usual GM or CN bullet variations, there are many, many variations in rim thickness, extracgtor groove and bevel, bullet crimps or no crimps, and if crimped, the size and shape of the crimps. It is easy over the years to accumulate ten or 15 variations of the ball cartridges made in Japan. There are also Thai ones, also unheadstamped, and then of course, many post-war renditions, mostly American, with and without headstamps. It is not the “three or four variation” cartridge some think it is.

Paul - the additional information is great. Thank Teri for all of us. I used to love the Nambu pistols and had a small collection of them within my overall auto pistol collection, which I sold in 1970-71 or thereabouts. I only have a Baby Nambu now, but it is complete with original holster, shoulder strap, all the cartridges, both matching magazines and even one of the shoulder boards off of the Japanese Captain’s uniform. A dear friend of mine, now deceased, took it in a one or won pistol fight in a “secure” area of the Philippines not long before the war ended. He gave it to me as a gift years ago.

Years ago I published an article on the Grandpa Nambu with stock that I had, in Shooting Times Magazine, and also a general article on Nambus in one of the Gun Digests. In those days, we didn’t know much at all about Nambus, really. My articles were pretty basic and probably with errors. Harry’s book “Handcannons of Japan,” and the followup edition, show how far we have come.

I have good notes on the post-war ammunition. Mr. Hiromatsu Ikeda, a former head of the Japanese Crime Lab, used to visit me at the store when he came to the US for AFTE meetings.
The last visit I had with him he gave me all his notes on the post-War ammo that he brought to AFTE for a some purpose. The headstamp photos make me envious! I also wrote a long article on Japanese post-War ammo for one of the club bulletins - I forget which one - and it was well received at the Crime Lab in Japan. A couple of small corrections were made to it. Embarrasingly, one of those corrections was to a mis-spelled English word they found in the article!

[quote=“JohnMoss”]The only Japanese-made pre-1946 8 mm Nambu rounds I have seen that are headstamped are blanks, usually found with a red wood bullet, although I am told that plain wood bulleted blanks are also found. Mine has a curved line with one tick mark above it. The few others I have seen all had two. I was told “on authority” that mine just had one of the two marks run off the head of the cartridge due to poor stamping, but the source had never seen my cartridge, and it simply is not the case. I don’t know the exact meaning of these marks.

These were in auction earlier this year. I didn’t bid, but saved the pictures. The left one had a red stained wood bullet (the heel of the bullet was unstained), the other was just an empty case. I think the characters ‘n’ and ‘shi’ are correct.

Which auction was that?

yahoo in Japan.

Tanega, (Your full handle is too long for a lazy old man) - thanks for showing the pictures. Mine does not have the red stain on the base, but is the “n” with one tick. I would have bid on both of those if foreigners could bid and they could be sent here. I know nothing of that auction and am surprised you can buy even inert ammo on it. I see both rounds had snapped primers. I haven’t been downstairs yet, to my collection, but I think the “n” one is oriented differently than mine, read at the 6 o’clock position rather than at 12 o’clock, which I believe is the case with mine.

Your picture confirms that I am right, however, and that what I was told about only existing in the “shi” form was incorrect.

Thanks for the nice pictures and additional information. The only mention I have found of a blank for the Nambu, other than Elk’s book, is a U.S. Army manual describing a blank for a cup-type discharger that clamped on the barrel of a Type 14 and was used for crowd control with tear gas grenades. Don’t know how true it is. Military manuals are not always correct on foreign ordnance, especially scarce items.

First Picture of four cartridges:

These are all Post-War Japanese-manufacture 8mm Nambu, and from left to right, they are:

  1. Ball round. Same headstamp as previously posted.
  2. Blank cartridge showing red bullet and normal stab bullet crimps.
  3. Dummy. Similar in pattern to WWII type, but totally different in construction. Solid brass bullet and case in one piece. Mock large copper primer set into the brass head. The knurled band on case and smooth band on bullet are the same ID used for pre-1946 dummies. The two holes are drilled straight through, giving the look of four holes.
    The pre-1946 dummies do not have these holes.


Second picture, heads of four cartridges:

These are the heads of the four cartridges pictured above. They are in the same order.

  1. Ball round showing “61” headstamp.

  2. Blank cartridge, showing the “n” headstamp, with one tick mark only above the curve. Note that this is a different orientation from the headstamp previously shown, which had the headstamp at the 6 o’clock position, rather than the 12 o’clock position as does this one.

  3. Dummy cartridge showing the large copper mock primer. I have placed it close to the blank to clearly show the difference in diameter between the two primers This dummy differs from the next one to its right in having a thiner rim, shorter “case”, longer “bullet,” slightly wider bullet cannelure and a more pronounced and slightly lower “case”
    shoulder. Regardless, it is believed that both are the same manufacture, but perhaps a year or so apart.

  4. The second dummy. Note that the base is somewhat smoother (less tool marks) than the one to its left.

Cartridges from the collection, and photos taken by, John Moss

I am sorry that I made one small error in this posting of photos - my own error, not Joe’s. The blank is NOT, of course, a post-war loading. It is pre-1946. The other three cartridges are post-war - the ball and the two dummies.