Siamese Mauser Type 46/66 Rifle
- Category
- Rifle
- Barrel
- 737 mm
- Weight, empty
- 3.90 kg
- Introduced
- 1903
About
What it is, and why it matters
The Siamese Mauser Type 46/66 is a full-length bolt-action infantry rifle built on the Mauser Gewehr 98 action by Japan's Koishikawa (Tokyo Artillery) Arsenal for the Kingdom of Siam (modern Thailand). Adopted in 1903 (R.S. 122) as the Type 46 rifle, it was originally chambered for the rimmed round-nose 8x50mmR Siam cartridge and fed from a five-round internal magazine loaded via stripper clips. Beginning in 1923 (B.E. 2466) surviving rifles were rebarreled and rechambered for the more powerful spitzer 8x52mmR Siamese 'Type 66' cartridge, producing the Type 46/66 designation. Like all Japanese-made Siamese Mausers it is noted for high build quality, a three-position wing safety and a distinctive reciprocating bolt dust cover.
The Siamese Mauser rifle was built in Japan rather than Germany: Tokyo's Koishikawa Arsenal forged and machined the parts for shipment to Bangkok, and the guns are stamped with a Thai Chakra emblem instead of a Mauser banner. When Siam upgraded to the flatter-shooting spitzer 8x52mmR 'Type 66' cartridge in 1923, armorers rebarreled the rifles and re-regulated the sights, giving these old Mausers a second service life through World War II.
Rifles rebarreled from the original 8x50mmR Siam to the 8x52mmR Siamese cartridge after 1923 are cataloged as Type 46/66. Barrel length (~29 in / 737 mm), overall length and empty weight are approximate figures typical of the full-length Siamese Mauser rifle pattern.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Koishikawa Arsenal
- Category
- Rifle
- Country
- Thailand
- Status
- Discontinued
- Produced
- 1903
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 737 mm
- Overall length
- 1245 mm
- Weight, empty
- 3.90 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Bolt action
- Firing mechanism
- Striker fired
- Trigger
- Single stage
- Capacity
- 5
- Magazine
- Internal
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Steel
- Stock
- Wood
- Finish
- Blued
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 685 m/s
- Muzzle energy
- 2744 J
- Effective range
- 500 m
Trajectory
What the round does downrange
Solved from the muzzle figures and the bullet. The dashed rule is the effective range on the record, and the crosses are the steps the solver returned.
No load solved for this record yetThe flight path is computed from a cartridge and a bullet. This record has no ammunition filed against its chambering, so there is nothing to solve.
Features
What it has
What the record lists as fitted, drawn from the catalogue.
Reciprocating dust cover
Controlled round feed
Stripper clip charger guide
Tangent leaf rear sight
Full length wood stock
Standing
How it compares
Each figure against the firearms of the same type and cartridge that record it, or of the same type where that cartridge has too few. Positions are read to the nearest tenth.
| Measurement | This firearm | Median | Position |
|---|---|---|---|
| Empty weightAmong 1,612 rifles | 3.90 kg | 3.50 kg | Heavier than about 60% |
| Overall lengthAmong 1,557 rifles | 1245 mm | 1080 mm | Longer than about 80% |
| Barrel lengthAmong 1,659 rifles | 737 mm | 584 mm | Longer than about 80% |
| Magazine capacityAmong 1,611 rifles | 5 | 5 | Holds more rounds than about 60% |
Answers
Questions about the Siamese Mauser Type 46/66 Rifle
How much does the Siamese Mauser Type 46/66 Rifle weigh?
The Siamese Mauser Type 46/66 Rifle weighs 3.90 kg (8.60 lb) empty.
What caliber is the Siamese Mauser Type 46/66 Rifle?
The Siamese Mauser Type 46/66 Rifle is chambered in 8x52mmR Siamese and 8x50mmR Siam.
How many rounds does the Siamese Mauser Type 46/66 Rifle hold?
The Siamese Mauser Type 46/66 Rifle holds 5 rounds, fed from an internal magazine.
How long is the Siamese Mauser Type 46/66 Rifle?
The Siamese Mauser Type 46/66 Rifle is 1245 mm (49.0 in) long overall, with a 737 mm (29.0 in) barrel.
Who makes the Siamese Mauser Type 46/66 Rifle?
The Siamese Mauser Type 46/66 Rifle is made by Koishikawa Arsenal (Japan). It was designed by Paul Mauser.
When was the Siamese Mauser Type 46/66 Rifle introduced?
The Siamese Mauser Type 46/66 Rifle was introduced in 1903.
How does the Siamese Mauser Type 46/66 Rifle operate?
The Siamese Mauser Type 46/66 Rifle uses a bolt action, and its firing mechanism is striker fired.
Compatibility
Which parts fit this firearm
Studio
Every part that mounts on this, resolved
Not a list the maker typed out: the answer comes from the mounts this firearm exposes and the interface each part needs, so it stays right when either one changes.
- Every part that mounts on any firearm in the catalogue
- Interface standards, platforms and fit overrides
- The same answers through the API and the MCP server
Requires a signed-in GunSpec account on the Studio plan. The answer is computed per part, so it is not part of the public record.
Provenance
What the record holds
Every figure above was taken from one of these pages. The confidence reflects how much of the record came from a page a claim can be checked against.
In service
- Royal Siamese Army
- 1903
- Royal Thai Armed Forces
- 1923
Provenance
Confidence in this record
60%
Stockists
Where to buy
Offers link straight to the shop. GunSpec never takes the order.
No shop has listed this firearm yet
Stock and prices come from the shops themselves. If you sell this firearm, you can list it and it appears here.
List a firearmMCP
Ask an assistant about it
The same record, reached the way a person asks for it rather than the way a program does.
Ask GunSpec
Works with
Point an MCP client at GunSpec and it answers from the catalogue rather than from memory. A free key covers the read tools.
API
The call that returns this record
The same fields, in the same units, from the same endpoint the page reads.
curl --request GET \ --url 'https://api.gunspec.io/v1/firearms/siamese-mauser-type-46-66-rifle' \ --header 'X-API-Key: your_key'{ "id": "siamese-mauser-type-46-66-rifle", "name": "Siamese Mauser Type 46/66 Rifle", "manufacturer": { "id": "koishikawa-arsenal", "name": "Koishikawa Arsenal", "countryCode": "JP", "foundedYear": 1871, "website": null, "logoUrl": null, "description": "Imperial Japanese Army arsenal in Tokyo that produced rifles including the Murata and Arisaka, operating from 1871 until relocated to Kokura in 1935.", "status": "defunct", "defunctYear": 1935, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-05-04 12:38:54", "updatedAt": "2026-05-04 12:38:54", "version": "9b554d58122b1e2995682948aeb9daf2784434a1d09071724b74d94445e76bb6" }, "category": { "id": "rifle", "name": "Rifle", "description": "Long-barreled firearms designed for accurate shooting" }, "country_of_origin": "TH", "year_introduced": 1903, "barrel_length_mm": 737, "weight_empty_g": 3900, "action_type": "bolt_action"}