When I put together the video and post a couple weeks ago on the Siamese/Thai Mauser, I figured I’d be clever and call it a Type 45/66, since it had been rechambered for the Type 66 cartridge. Well, I got an email from Teri the Nambu Lady politely informing me that I’d totally mangled the designation (my words, not hers). In fact, it was a Type 46 rifle (the Thai calendar doesn’t start at January 1st, so our year of 1903 was partly 2445 and partly 2446 by their calendar). And while the modernized spitzer cartridge was the Type 66, the converted Mauser rifles were not given that name. Instead, as it turns out, the Type 66 rifle was a totally different gun purchased by the Siamese government, and she hooked me up with some information on that rifle (thanks, Teri!).
Specifically, the Type 66 was basically a copy of the Type 38 Japanese Arisaka make under contract by the Tokyo arsenal for Siam. By happy chance, Teri has examples of all three rifles, and sent a couple photos showing them side by side:
When the Siamese military decided to update their small arms to the 8x52R spitzer cartridge, King Vajiravudh had succeeded King Chulalongkorn (his father), who had been in power when the Type 45 rifles were originally purchased. The new King had been educated in England, and actually wanted to replace the rifles all with .303 SMLEs (and he did buy 10,000 of them for some of his elite forces). His generals talked him out of that idea because it would require replacing all their machine guns as well to maintain a single cartridge. Instead, he was approached by a Japanese export firm that was marketing the Type 38 Arisaka rifle. These could be obtained in the new 8x52R cartridge quite a bit cheaper than Enfields would be, and the King decided to order 50,000 of them in 1923, under the designation Type 66 (the Thai year being 2466).
Interestingly, despite bearing a very close resemblance to the Type 38 Arisaka, it and the Type 66 have virtually zero interchangeable parts – even the screws in the Type 66 are cut to a different thread pitch. The stocks are shorter, the bands are held by machine screws instead of springs, the front sight base is integral to the barrel, and the rear sight is of the Mauser tangent type instead of the Japanese ladder style. The Type 66 was supplied with bayonets that followed the pattern of the Japanese Type 30 bayonet closely, but are again not interchangeable because the Type 66 has a slightly different muzzle diameter than the Type 38 Arisaka.
Production of the 50,000 rifle order ultimately took five years, with the final deliveries not taking place until 1928. The reason for this slow production isn’t known, although it could be the Siamese government wanting to pay in yearly installments, or possibly the result of damage to the Tokyo production facilities from the catastrophic Tokyo earthquake of 1923.
Type 66 rifles are very rare in the US today, as they were not surplussed by Thailand until the 1970s, and the 1968 GCA had curtailed the import of military arms. As a result, most of the Type 66s went to Europe and the Commonwealth nations instead of the US.