Siamese 8mm ammunition

I’ve been pondering on the paradox of Siam opting for a unique cartridge (and rifle design) at a time when most countries without an indigenous munitions industry were happy to adopt one of the ‘proprietary’ calibers offered by the big producers.

Does anyone know whether trials were conducted by the Siamese to determine what caliber they were going to adopt and tests done with different case, powder and bullet combinations? It seems unlikely that they just made up their mind to adopt the 8x50R round without some kind of research into its effectiveness. This cartridge has a passing similarity (though no more than that) to the Austrian 8x50R, was there collaboration at any time between the two countries?

The same questions apply to the adoption of the 8x52R in 1923. Was this case decided upon because the existing rifles could be rechambered in it without the need for new barrels. the extra case length would have accounted for erosion to the leade whilst the similar rim diameter would have allowed the bolt to be used without modification. Or was there a more scientific approach to the change?

In anticipation.

Happy collecting,



The similarity between the M.88 8x50R Austrian Mannlicher and the Type 45 8x50R Siamese Mauser cartridges is so great that it could hardly have been a coincidence. During the 1890s the Austrian M.88 Mannlicher became the first small calibre rifle to be used by the Siamese, before it was superseded by the Japanese-made Mauser in 1902.

Indeed there is some evidence that for a time the two rifles were in service concurrently with the Siamese army before the Mannlicher was finally withdrawn. Kiesling in his “Bayonets of the World” records an Austrian-made M.88 Mannlicher bayonet, thought to have seen service with Bulgaria but with later Siamese markings added. These he translates as “46th Year type bayonet”, or 1903. And Herb Woodend once told me that he had personally seen Austrian-made 8mm Mannlicher clips holding Type 45 cartridges that had “obviously been there for many years”.

Herb’s observation raises the possibility that the Type 45 round was intentionally designed to chamber in the 8mm Mannlicher as well as the Siamese Mauser, and a comparison of their measurements suggests that this would be entirely possible. The Type 45’s neck is about 2mm longer than the Mannlicher’s, and the shoulder set slightly lower, and its case diameter just below the shoulder is 0.5mm less (11.5mm compared with 12mm). The need for some commonality in ammunition supply would explain the curious use of a rimmed cartridge in a Mauser rifle with the disadvantages this brings, eg having to design its box magazine with a backward slant to prevent feeding difficulties.

It is perhaps more doubtful whether the Mannlicher 8x50R would chamber successfully in the Mauser rifle, but it would be interesting to find out.

John E

There is no problem loading and shooting an Austrian 8 x 50 in a Siam.






Thanks for settling that question. I wonder why the Siamese decided they wanted a slightly different cartridge, instead of carrying on using the 8x50R Mannlicher? It may have been a question of national pride rather than a strictly military decision.

John E

I would think that the later Thai cartridge (designation not at hand) with the spitzer bullet and more angular shoulder was designed, like the M30 cartridge introduced in Austria and Hungary at about the same time, to provide improved performance without extensive alteration to the arms themselves. Original barrels, bolt assemblies, and clips could be retained, only a chambering reamer being needed for the conversion. As I recall Moetz suggested that the performance of the 8m/m M93 Austrian cartridge was marginal with its relatively small powder capacity and that big heavy 244 gr. bullet. Jack

Fred Honeycutt, JR. in his book Military rifles of Japan states “Thailand purchased a variant of the Model 1898 Mauser from Japan about 1903. Patterned the Model 1903 Siamese Mauser, it is chambered for a smokeless powder version of the 8mm Type 22 Murada rimmed cartridge”.


Are you sure your picture is of a Siamese Mauser? It looks like a Arisaka Type 38 with a Siamese crest. The Thai lettering below the crest says “Type 66” (66=1923) which would make it an 8x52mmR not an 8x50mmR.

Mine has R.S.121 (1903) in Thai letters below the crest. The rear sight arch has been reground (top half of the numbers on the side of the arch missing) which makes it one that has been rebuilt and converted from 8x50mmR to 8x52mmR. It will feed, chamber and the bolt will close on an 8x50mmR cartridge but I would imagine the case would come out looking a lot different than when it went in when fired.

Phil mentions Honeycutt’s statement that the 8x50R Type 45 Siamese cartridge was based on the 8x52.5R M.87 Murata round, and this is certainly a possibility worth examining. When they requested Mauser to design a replacement for their 8mm Mannlicher rifles, it would have been logical for Siam to have specified that it should be chambered for the existing 8x50R Austrian round, to ensure commonality of ammunition supply. And in fact there is no record of the Type 45 Siamese cartridge having been made in Germany until it appeared in the DWM lists as DWM.518 which, following the chronology of DWM’s numbering, would be in 1906.

Mauser made the first few rifles for trials, but then production was turned over to the Koishikawa Arsenal in Tokyo, and early production of the Type 45 cartridge also took place in Japan. Japan had already produced the 8x52.5R Murata round, developed in 1887 and which was dimensionally very close to the 8x50 Mannlicher. In fact with a slight reduction in case length and a slight increase in rim diameter, it should be close enough to have doubled as the cartridge for both the 8mm Mannlicher and the Siamese Type 45. Much would depend on its shoulder height and I haven’t had an opportunity to examine one. Is anyone lucky enough to be able to compare them?

Regarding the improved 8x52R Type 66 Siamese cartridge, this has a slightly greater base diameter (12.8mm compared with 12.4mm for the Type 45). As a result it fits too tightly to strip easily from chargers made for the Type 45, and one with a slightly increased flange-flange distance, but otherwise identical, was therefore made for it. Both were of typical Japanese design, resembling a slightly enlarged Arisaka charger.

John E

(edited once to correct typo in date of DWM.518)

John - I am interested to know what makes you so specific that the 8x50R Siamese was introduced into DWM production in 1905 when case #511 was a 7X57 Chinese Mauser M06 and #513 was the 45 M06 ?

John: I had not picked up on the different base sizes of the two cartridges. Now I’ll have to check and see which of the two clips my single specimen is (tho it’s likely the later and–I assume–commoner one). Thanks, Jack

There has been much controversy about “dimensional differences” between the 8x50R (M93) Austrian, the 8x53R (M88/90 )Austrian , and the 8x50R (Type 45–M1902/3) Siamese.

For all practical purspose, Siam bought from Steyr in 1897-8, a batch of Mannlicher M88/90 or M90 Rifles and carbines And bayonets, the left overs of a defaulted Bulgarian Contract (The Bulgarians then acquired M95 rifles and carbines in 1903-1914);
Whichever of the Austrian cartridges the Early Mannlichers were chambered for, the Ammo was interchangeable. (M88/90 and M93 Cartrridge )

Siam then in 1899 contacted Mauser for trials rifles (7x57 M1898/1902 design) as well as a possible “8x50R” type Mauser rifle. Mauser at the time had just released the M98 design, also in a Sporting Version Action for British Rimmed Cartridges, and designed a “slanted” magazine-well Rifle, with a Small ring diameter reciever, but M98 Three lug Bolt design, and Long Firing Pin ( as in the Commercial M1904 and the Turk M1903), and with the M1902/1904 Commercial rear sight.

As Mauser Oberndorf was fully occupied with both German Imperial orders and the Turkish Contract, as well as the M1904 Commercial, they Licensed out the manufacturing to the Dai Nippon Arsenal ( Export arm of Koishikawa Imperial Army Arsenal), to manufacture the design, along with any improvements that the Siamese may have requested.

The Forward moving Bolt/receiver cover ( also used on the short-lived Japanese Type 35 rifle (between the T30 and 38) may have been a Japanese Suggestion, for the problems of Tropical use. Why forward moving and not-Bolt-handle-actuated, I don’t know…maybe because the forward sliding was a “silent” item (the Bolt cover on T30/38s was a rattler, and in practice, usually discarded in combat).

As to the ammunition, and the Rifling/Bore relationships, they followed Austro-Hungarian practice… ( Bore .315, Projectile .322-324 Flat based; Grooves .328-330, so that “Base Upset Obturation” of the long cylindrical bullet allowed for a driving band to gas seal, and the rest of the long jacket barely cut by the rifling, and so reduced jacket-to-bore friction and Metal fouling. ( steel jacket bullets used, with or without Ni- plating.)

The slighly different dimensions were probably a function of extactor design differences, and tolerance clearances differances due to being used in a Camming turnbolt rifle rather than a Straight-pull action with less “camming” extraction power. The relationsip to the 8x52.5 (aka 53)R Murata is tenuous at best, the Murata case design having been obsoleted by the smaller 6,5mm Type 30 cases. Japan’s last use of the Murata was in the Russo-Japanese War, but usually as a second line arm only ( non “attack” units). Front line infantrey were armed with T30 rifles in 6,5mm).

The original T45/46 (Mauser) design rifles are Identifiable by the complete ramps of the M1902 patent rear sight, with full Siamese numbers (digits) stamped there-on (similar to the 6,5mm M1904 Vergueiro rear sights).

After WW I, with the Observations gleaned from Siamese Officers who had been attached to the French and British Armies in France, it was decided to upgrade the ammunition to a Spitzer bullet, for both MG and rifle. In a financially straightened atmosphere, and bolstered by the New King’s formation of the “Tiger” Corps with BSA .303 rifles (Type 62, 1919) using spitzer .303 bullets, the Siamese, in conjucntion with Koishikawa, decided on a new cartridge, being a slightly larger 8x52R cases, with a 168 grain flat based bullet of .324 diameter, to function in the re-chambered 8x50R barrels. The OAL of the new T66 (1923) cartridge was the same as the original T45 cartridge, so no magazine changes were required…also, the Rim diameter was also identicxal to the T45, so no Bilt face adjustments or extyractor adjustments required, ands the Body dimensions were increased slightly, to allow for a New (T66) Chamber reamer to fully “CVlean up” the existing chamber from Base to Mouth; that way, the T45 case head (.490) was increased to .500-505 (T66); the shoulder was moved forward slightly to change the angle wrt the Austrian case; and of course the extra length also cleaned up some of the eroded throat of the rifling, still allowing for the Base Upset to occur in the normal fashion.

The rear sight ramp was re-cut (or precision ground) to reflect the flatter shooting Spitzer Load… All this conversion work was done in the recently modernised RTA (Royal Thai Army) Arsenal at Bung-soo, just outside Bangkok. The Country’s name had been changed from “Siam” to Thailand" some time in this period but the change was not universally adopted until after WW II.

At the same time, Siam had ordered a New Rifle from Japan, based on the Arisaka T38 Action, but in 8x52R; due to then 1923 Kanto Earthquake, wihich damamged the Koishikawa factory (Near Yokohama, down from Tokyo, the Delivery of the T66 (Arisaka) Rifles dragged almost to 1930. In typical Japanese fashion, the T66 was fully engineered to be non-interchangeable with the T38 (Japanese) Rifle, althought he design was the same; Only the bayonets were interchangeable. Siam also was buying Surplus T38 rifles at the time (in 6,5mm).

For the MGs, it was a simple case of substituting the old barrels for new ones (Vickers mostly, after WW I) and recalibrating the Sights. Siam continued acquiring ammo from Japan, began making their own, and after WW II into the 1960s, had Kyb\nock make 8x52R ammo and empty cases for them for loading in Bungsoo.

A very intersting cartridge history from a much under-reasearched Country.

Doc AV
AV Ballistics.

Brad –

Sorry, my mistake. ‘1905’ was a typo on my part, and the date for DWM’s 8x50R Type 45 Siamese should of course be 1906 (and I checked the date from the DWM Case Number list in your “E.S.C.” book too!)

John E

During a four year stint in Denmark during the 1990s I tried to gain access to some military records which was unsurprisingly unsuccessful but I managed to glean some small tidbits of information from the index system in the archives on my fruitless application. It will come as no surprise that in 1922 and 1923 that Madsen MGs were made and delivered to Siam. It has always intrigued me that the then new 8x52 type 66 cartridge has the same base size as the 8x58 rimmed Krag cartridge.
The points previously raised in this thread about the importance of cleaning up the whole chamber and throat are especially valid and considering the corrosive nature of environment and ammunition hardly surprising when approached practically. Someone had to design the type 66 and someone had to make the chamber reamers.
Coincidence or not why that size? Had to be something I guess. Incidently 45-70 is very similar in base size too.

The mention of the .45-70 is appropriate. Back in the late 60’s-early 70’s, one could buy the Siamese Mausers dirt-cheap. I bought one for, as I remember, about $20. There was a cottage industry in using the Siamese Mauser actions for conversion to sporters in .45-70, and I think some were commercially sold, at least I seem to remember ads for same in the gunmags of that time. In 1991, I sold my rifle to a gunsmith in Laredo TX who was buying them up as he found them to use the actions for conversion to .45-70 sporters, and I remember him saying that he did a good business in them. Mine had the sliding bolt cover. Its metal condition was very good but the wood was badly beaten up. I don’t remember the condition of the bore. I’d guess most of the Siamese Mausers imported to the US met the conversion fate. However, I personally have never seen a SM sporter in .45-70, so those that have them probably keep them.

I had originally planned to shoot mine, but the cartridge conversion cost and difficulty discouraged me from doing so, given the small amount I had originally paid for the rifle.

I was stationed in Thailand in 1969 and had an opportunity to go through the public areas around the Palace and I also spent a day in the Royal Thai Army Arsenal in Bangkok. At that time they were making 30-06 (RTA 69 hst) and planning to manufacture 5.56mm. They were also doing a test batch of 38 special and reloading 8mm Siamese cases with teak wood bullets. The Thai guard on the steps of the Ministry of Defense had a rifle loaded with 8mm Siamese ammunition. On the grounds near the Palace was a building that I understood to be the original old Royal Arsenal. A quick look on the internet says it dates back to before 1748. In front was a combination between a light field piece with two iron wheels and a hugh revolver with a great big cylinder that appeared to be chambered for a cartridge that must have been about 30mm and a case that could have been 8" to 10" long based on the size of the cylinder. According to the US Army Major who was assigned to the Thai Army Arsenal that walked me around that day, the Thai’s have a long history with firearms and have played with a lot of things but didn’t ever develop the capability for large scale production. the 30-06 was being loaded on ex-US machinery and the 8mm was being loaded or German machinery from before WWII. There was other machinery further back in the building but it was not in use and I didn’t ask about it. Based on what I saw, I am pretty confident that at least some of the Thai 8mm, perhaps most of it was loaded at the Thai arsenal.

IThe Thai’s are strongly nationalistic and are the only country in the region that was never a colony of a European power. They are very proud of that fact and the fact that they have their own alphabet, and number system (both derived from Sanskirt), and their own unique culture. My guess is that they intentionally decided on a unique caliber out of national pride. After all, in the same timeframe, the Chinese were testing both the Enfield and Mannlicher rifles and out of this they developed their own version of the 8x50mm M but in 7.65mm like the British 303. This was an entirely original design by the Chinese for their Shanghai (Kiangnan) rifles (IAA Journal 414).

Woodin Labs in an article in Journal 332 indicates that the 8mm Siamese cartridge was “made by Siam’s only cartridge producer, the national Arsenal in Bangkok from the cartridge adoption in 1902 through at least the beginning of WWII”. Bill Woodin also says that prior to WWII ammunition was also supplied by England (Kynoch), Germany (DWM) and probably Japan. In addition HA of Denmark supplied cases in the 1920s. Sako in Finland produced this caliber for use in surplus rifles in the 1960s and 1970s.



Just to confirm the production of RTA 5,56 cartridges, I have found some RTA 5,56 M200-type blanks mixed in with Aussie ADI blanks and ball from Field Fire ranges 07-08; Either a Lot bought in by ADI, or some cases from an RTA unit on joint training exercises at Shoalwater Bay.

5,56 RTA cases are very similar to LC M200, but no cannelure around base of case. Red primer seal.


Hotchkiss draws remake by SFM

Amic, Dan

Thanks, Munavia…that indicates that if Hotchkiss made drawings of the 8x50R Siamese T45 cartridge, and even its five round clip, that they were maybe supplying Clips for Rifle ammo AND even M1897 or M1905 Hotchkiss MGs to Siam? ( The French Military had the ascendancy with Siam’s Army at the time…also being “Colonial neighbours” in Indochina.

Has anybody got any info regarding Hotchkiss Guns for Siam before WW I?
And if SFM supplied any 8x50R ammo to Siam as well?

Doc AV
AV Ballistics.

This does not help much with the history, but these two 1953 Kynoch drawings (one Metric, one Imperial) for the 8mm Siamese tracer do at least give detailed dimensions.


I have a neglected collection of rifle-caliber AP loads, and one of the things that I have looked for over the years are the 8x52R AP and API loads. If I remember correctly, the API load was supplied by Kynoch, and had a gray or gray/blue tip? Does anyone have a pic of those types?

They are around in the UK, but I do not have one. i wil try to find a picture for you. Jim may have one.