HK MP5A3
- Category
- Submachine Gun
- Barrel
- 225 mm
- Weight, empty
- 2.90 kg
- Introduced
- 1970
About
What it is, and why it matters
The HK MP5A3 is a select-fire submachine gun chambered in 9x19mm Parabellum, produced by Heckler & Koch GmbH since 1970. This German-manufactured firearm reflects the engineering traditions and quality standards of its country of origin, designed to meet the demands of both civilian and professional users in a competitive global marketplace. Featuring a 30-round magazine capacity, this submachine gun offers generous firepower for duty use and home defense. The 8.9-inch barrel maximizes accuracy potential and ballistic performance, making this an excellent choice for target shooting, competition, or field use. At 2900g (102.3 oz), this is a substantial firearm whose weight contributes to reduced felt recoil and enhanced stability during precision shooting. The steel frame provides a solid, premium feel with the durability to withstand decades of regular use and thousands of rounds. This firearm represents its manufacturer's commitment to delivering a well-engineered, reliable product that serves the needs of discerning shooters seeking quality, accuracy, and dependable performance from a proven platform.
The MP5A3's retractable stock made it the preferred variant for vehicle crews and close-protection teams who needed a compact weapon that could still be shoulder-fired accurately. The three-round burst trigger group was particularly popular with units concerned about ammunition conservation.
The MP5 gained worldwide recognition during the 1980 Iranian Embassy siege in London, where the British SAS used it during a televised hostage rescue operation. The roller-delayed blowback system provides exceptional accuracy and controllability compared to direct blowback submachine guns.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Heckler & Koch
- Category
- Submachine Gun
- Country
- Germany
- Status
- In production
- Produced
- 1970
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 225 mm
- Overall length
- 680 mm
- Height
- 133 mm
- Width
- 32 mm
- Weight, empty
- 2.90 kg
- Weight, loaded
- 3.40 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Roller delayed blowback
- Firing mechanism
- Hammer fired
- Trigger
- Single stage
- Trigger pull
- 37.5 N
- Capacity
- 30
- Magazine
- Detachable box
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Steel
- Stock
- Polymer
- Finish
- Black
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 400 m/s
- Muzzle energy
- 650 J
- Effective range
- 200 m
- Rate of fire
- 800 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.
Retractable stock
Three round burst- Full auto
- Semi auto
Roller delayed blowback
Navy trigger group
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 201 9x19mm Parabellum submachine guns | 2.90 kg | 3.18 kg | Lighter than about 60% |
| Overall lengthAmong 200 9x19mm Parabellum submachine guns | 680 mm | 723 mm | Shorter than about 60% |
| Barrel lengthAmong 202 9x19mm Parabellum submachine guns | 225 mm | 213 mm | Longer than about 60% |
| Magazine capacityAmong 204 9x19mm Parabellum submachine guns | 30 | 32 | Holds fewer rounds than about 70% |
Answers
Questions about the HK MP5A3
How much does the HK MP5A3 weigh?
The HK MP5A3 weighs 2.90 kg (6.39 lb) empty and 3.40 kg (7.50 lb) loaded.
What caliber is the HK MP5A3?
The HK MP5A3 is chambered in 9x19mm Parabellum.
How many rounds does the HK MP5A3 hold?
The HK MP5A3 holds 30 rounds, fed from a detachable box magazine.
How long is the HK MP5A3?
The HK MP5A3 is 680 mm (26.8 in) long overall, with a 225 mm (8.86 in) barrel.
Who makes the HK MP5A3?
The HK MP5A3 is made by Heckler & Koch (Germany). It was designed by Tilo Moller.
When was the HK MP5A3 introduced?
The HK MP5A3 was introduced in 1970.
How does the HK MP5A3 operate?
The HK MP5A3 uses a roller delayed blowback 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
- German Federal Police (GSG 9)
- 1977
- British Special Air Service (SAS)
- 1980
- United States Navy SEALs
- United States
- Federal Bureau of Investigation
- United States
- French GIGN
- France
- Bundeswehr
- 1966
Provenance
Confidence in this record
87%
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/hk-mp5a3' \ --header 'X-API-Key: your_key'{ "id": "hk-mp5a3", "name": "HK MP5A3", "manufacturer": { "id": "heckler-koch", "name": "Heckler & Koch", "countryCode": "DE", "foundedYear": 1949, "website": "https://www.heckler-koch.com", "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": "ae60994f5b45d604da21fcd14b728cfa9d2e62000c92e596de4c48c4be768979" }, "category": { "id": "submachine-gun", "name": "Submachine Gun", "description": "Automatic firearms chambered in pistol calibers" }, "country_of_origin": "DE", "year_introduced": 1970, "barrel_length_mm": 225, "weight_empty_g": 2900, "action_type": "roller_delayed_blowback"}