FN MAG
- Category
- Machine Gun
- Barrel
- 630 mm
- Weight, empty
- 11.79 kg
- Introduced
- 1958
About
What it is, and why it matters
The FN MAG (Mitrailleuse d'Appui Général, meaning General Purpose Machine Gun) is a Belgian 7.62x51mm NATO general-purpose machine gun designed in the early 1950s by Ernest Vervier at Fabrique Nationale. Entering production in 1958, the MAG combines the proven feed mechanism of the German MG 42 with the inverted gas operation system derived from the Browning BAR. It features a gas-operated, open-bolt design with a quick-change barrel system requiring less than 6 seconds for replacement. The weapon incorporates an adjustable gas regulator allowing users to set cyclic rates between 650-1,000 rounds per minute for optimal reliability under varying conditions. Known for exceptional reliability, accuracy, and durability, the FN MAG has become one of the most widely adopted machine guns in history, serving over 80 countries worldwide. It remains in production and active service across NATO forces and beyond, designated as the M240 in the United States, L7 in the United Kingdom and Commonwealth nations, and C6 in Canada.
The FN MAG's design brilliantly combines the best elements of two World War II weapons: the feed mechanism from the German MG 42 and the inverted gas operating system from the Browning Automatic Rifle. Sweden was the first country to adopt it in 1958, originally chambered for their 6.5x55mm cartridge.
The FN MAG was initially adopted by Sweden in 1958 as the Ksp 58, originally chambered in 6.5x55mm before the standard 7.62x51mm NATO version became widespread. The weapon's design brilliantly combines elements from two of WWII's most successful firearms: the MG 42's belt-feed mechanism and the BAR's gas operation (inverted). The quick-change barrel system enables sustained fire capability, a critical feature for a general-purpose machine gun. Modern variants feature MIL-STD-1913 Picatinny rails for mounting optics and accessories. The weapon is manufactured under license in multiple countries including the United States, United Kingdom, Canada, Sweden, Argentina, Egypt, and India. The M240L variant, adopted by the U.S. military in 2010, reduces weight by 2.5kg through the use of titanium components. The MAG can be deployed on bipods for infantry use, tripods for sustained fire roles, or vehicle/aircraft mounts for coaxial and pintle applications.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- FN Herstal
- Category
- Machine Gun
- Country
- Belgium
- Status
- In production
- Produced
- 1958
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 630 mm
- Overall length
- 1260 mm
- Weight, empty
- 11.79 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated long stroke
- Firing mechanism
- Open bolt
- Trigger
- Automatic only
- Magazine
- Belt fed
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Chrome lined steel
- Stock
- Polymer
- Finish
- Parkerized
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 840 m/s
- Muzzle energy
- 3350 J
- Effective range
- 800 m
- Maximum range
- 1800 m
- Rate of fire
- 650 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.
Features
What it has
What the record lists as fitted, drawn from the catalogue.
Quick change barrel
Chrome lined barrel
Chrome lined chamber
Gas regulator
Picatinny rail
Bipod
Open bolt
Belt fed
Slotted flash suppressor
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 32 7.62x51mm NATO machine guns | 11.79 kg | 10.51 kg | Heavier than about 80% |
| Overall lengthAmong 32 7.62x51mm NATO machine guns | 1260 mm | 1149 mm | Longer than about 80% |
| Barrel lengthAmong 32 7.62x51mm NATO machine guns | 630 mm | 559 mm | Longer than about 90% |
Answers
Questions about the FN MAG
How much does the FN MAG weigh?
The FN MAG weighs 11.79 kg (25.99 lb) empty.
What caliber is the FN MAG?
The FN MAG is chambered in 7.62x51mm NATO.
How long is the FN MAG?
The FN MAG is 1260 mm (49.6 in) long overall, with a 630 mm (24.8 in) barrel.
Who makes the FN MAG?
The FN MAG is made by FN Herstal (Belgium). It was designed by Ernest Vervier.
When was the FN MAG introduced?
The FN MAG was introduced in 1958.
How does the FN MAG operate?
The FN MAG uses a gas operated long stroke action, and its firing mechanism is open bolt.
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
- Belgian Armed Forces
- 1958
- United States Army
- 1977
- United States Marine Corps
- 1991
- British Armed Forces
- 1961
- Australian Defence Force
- 1963
- Canadian Armed Forces
- 1961
- Swedish Armed Forces
- 1958
- New Zealand Defence Force
- 1976
- Netherlands Armed Forces
- Netherlands
- Spanish Armed Forces
- Spain
Provenance
Confidence in this record
88%
Stockists
Where to buy
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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/fn-mag' \ --header 'X-API-Key: your_key'{ "id": "fn-mag", "name": "FN MAG", "manufacturer": { "id": "fn-herstal", "name": "FN Herstal", "countryCode": "BE", "foundedYear": 1889, "website": "https://www.fnherstal.com", "logoUrl": null, "description": null, "status": null, "defunctYear": null, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-02-11 23:44:38", "updatedAt": "2026-02-18 03:43:43", "version": "868b12ac455d24b965edddf486bafb1892f606961311b1ab9907556e3a23b075" }, "category": { "id": "machine-gun", "name": "Machine Gun", "description": "Fully automatic firearms for sustained fire" }, "country_of_origin": "BE", "year_introduced": 1958, "barrel_length_mm": 630, "weight_empty_g": 11790, "action_type": "gas_operated_long_stroke"}