M85 Machine Gun
- Category
- Machine Gun
- Barrel
- 1016 mm
- Weight, empty
- 29.48 kg
- Introduced
- 1959
About
What it is, and why it matters
The M85 is an American .50 caliber (12.7x99mm NATO) heavy machine gun designed by AAI Corporation to replace the Browning M2HB with a shorter, lighter weapon suitable for the cramped cupola mounts of armoured vehicles. It is recoil-operated, fires from an open bolt and offers two selectable cyclic rates - a lower rate for ground targets and a much higher rate for anti-aircraft use. Reliability shortfalls limited its adoption, and it was eventually phased out in favour of the M2.
The M85 was meant to retire the legendary Browning M2 by being shorter and lighter for tank cupolas - but it never matched 'Ma Deuce' for reliability, and the gun it was built to replace ultimately outlived it in US service.
Fielded primarily on the cupola of the M60 series of main battle tanks and on the LVTP-7 amphibious assault vehicle. The dual-rate mechanism gave roughly 400-500 rpm against ground targets and a much higher rate against aircraft.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- AAI Corporation (Textron Systems)
- Category
- Machine Gun
- Country
- United States
- Status
- Out of production
- Produced
- 1959 to 1997
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 1016 mm
- Overall length
- 1384 mm
- Weight, empty
- 29.48 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Short recoil
- Firing mechanism
- Open bolt
- Magazine
- Belt
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
- 880 m/s
- Muzzle energy
- 16220 J
- Effective range
- 2196 m
- Maximum range
- 6703 m
- Rate of fire
- 500 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.
Belt fed
Left or right hand feed- Dual cyclic rate
- Fixed headspace
Compact receiver
Cupola mount- Solenoid fired
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 261 machine guns | 29.48 kg | 10.50 kg | Heavier than about 90% |
| Overall lengthAmong 260 machine guns | 1384 mm | 1156 mm | Longer than about 80% |
| Barrel lengthAmong 257 machine guns | 1016 mm | 605 mm | Longer than about 90% |
Answers
Questions about the M85 Machine Gun
How much does the M85 Machine Gun weigh?
The M85 Machine Gun weighs 29.48 kg (64.99 lb) empty.
What caliber is the M85 Machine Gun?
The M85 Machine Gun is chambered in .50 BMG.
How long is the M85 Machine Gun?
The M85 Machine Gun is 1384 mm (54.5 in) long overall, with a 1016 mm (40.0 in) barrel.
Who makes the M85 Machine Gun?
The M85 Machine Gun is made by AAI Corporation (Textron Systems) (United States).
When was the M85 Machine Gun introduced?
The M85 Machine Gun was introduced in 1959 and discontinued in 1997.
How does the M85 Machine Gun operate?
The M85 Machine Gun uses a short recoil 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
- United States Army
- 1959
- United States Marine Corps
- United States
Provenance
Confidence in this record
70%
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/m85-mg' \ --header 'X-API-Key: your_key'{ "id": "m85-mg", "name": "M85 Machine Gun", "manufacturer": { "id": "aai-corporation", "name": "AAI Corporation (Textron Systems)", "countryCode": "US", "foundedYear": 1950, "website": "https://www.textronsystems.com", "logoUrl": null, "description": null, "status": null, "defunctYear": null, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-06-21 23:00:46", "updatedAt": "2026-06-21 23:00:46", "version": "e5da025c597cd46db144f928652cc8a4086810da5d7e7cc7b5faa3f2288277ca" }, "category": { "id": "machine-gun", "name": "Machine Gun", "description": "Fully automatic firearms for sustained fire" }, "country_of_origin": "US", "year_introduced": 1959, "barrel_length_mm": 1016, "weight_empty_g": 29480, "action_type": "short_recoil"}