Enfield EM-2
- Category
- Assault Rifle
- Barrel
- 623 mm
- Weight, empty
- 3.41 kg
- Introduced
- 1951
About
What it is, and why it matters
The Enfield EM-2 is a British experimental select-fire assault rifle chambered in the intermediate .280 British (7x43mm) cartridge. Developed at the Royal Small Arms Factory in the late 1940s, it pioneered the compact bullpup layout with an integral carrying handle and a built-in optical sight, well ahead of its contemporaries. It was briefly adopted in 1951 as the 'Rifle, Automatic, caliber .280, Number 9 Mark 1' but never entered operational service, as Winston Churchill's incoming government reversed the decision to pursue NATO standardisation on the 7.62x51mm cartridge.
The EM-2 was unofficially known as the 'Janson rifle' after its lead designer Stefan Kenneth Janson, an assumed name of the Polish engineer Captain Kazimierz Januszewski, who had fled to Britain during the Second World War.
Only a small number of prototypes were built. Its forward-thinking bullpup design heavily influenced later weapons such as the SA80/L85.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Royal Small Arms Factory
- Category
- Assault Rifle
- Country
- United Kingdom
- Status
- Prototype
- Produced
- 1951 to 1951
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 623 mm
- Overall length
- 889 mm
- Weight, empty
- 3.41 kg
- Weight, loaded
- 4.15 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated
- Firing mechanism
- Hammer fired
- Trigger
- Select fire
- Capacity
- 20
- Magazine
- Detachable box
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Steel
- Finish
- Phosphate
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 745 m/s
- Muzzle energy
- 2519 J
- Effective range
- 700 m
- Rate of fire
- 600 rpm
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.
Bullpup layout
Integral carrying handle
Integral optical sight
Gas operated action
Select fire
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 274 assault rifles | 3.41 kg | 3.59 kg | Lighter than about 60% |
| Overall lengthAmong 271 assault rifles | 889 mm | 915 mm | Shorter than about 60% |
| Barrel lengthAmong 271 assault rifles | 623 mm | 415 mm | Among the longest tenth |
| Magazine capacityAmong 276 assault rifles | 20 | 30 | Among the smallest capacities |
Answers
Questions about the Enfield EM-2
How much does the Enfield EM-2 weigh?
The Enfield EM-2 weighs 3.41 kg (7.52 lb) empty and 4.15 kg (9.15 lb) loaded.
What caliber is the Enfield EM-2?
The Enfield EM-2 is chambered in .280 British.
How many rounds does the Enfield EM-2 hold?
The Enfield EM-2 holds 20 rounds, fed from a detachable box magazine.
How long is the Enfield EM-2?
The Enfield EM-2 is 889 mm (35.0 in) long overall, with a 623 mm (24.5 in) barrel.
Who makes the Enfield EM-2?
The Enfield EM-2 is made by Royal Small Arms Factory (United Kingdom). It was designed by Stefan Kenneth Janson.
When was the Enfield EM-2 introduced?
The Enfield EM-2 was introduced in 1951 and discontinued in 1951.
How does the Enfield EM-2 operate?
The Enfield EM-2 uses a gas operated action, and its firing mechanism is hammer 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
- British Armed Forces
- 1951
Provenance
Confidence in this record
82%
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/em-2-rifle' \ --header 'X-API-Key: your_key'{ "id": "em-2-rifle", "name": "Enfield EM-2", "manufacturer": { "id": "royal-small-arms-factory", "name": "Royal Small Arms Factory", "countryCode": "GB", "foundedYear": 1816, "website": null, "logoUrl": null, "description": null, "status": null, "defunctYear": null, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-04-05 22:24:37", "updatedAt": "2026-04-05 22:24:37", "version": "cc7e952d6e6fac881044862f14fe6925a2806206d419f090a4b5fea3fe05740a" }, "category": { "id": "assault-rifle", "name": "Assault Rifle", "description": "Selective-fire rifles chambered in intermediate cartridges" }, "country_of_origin": "GB", "year_introduced": 1951, "barrel_length_mm": 623, "weight_empty_g": 3410, "action_type": "gas_operated"}