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HK G3A4

HK G3A4
Category
Battle Rifle
Barrel
450 mm
Weight, empty
4.70 kg
Introduced
1974

About

What it is, and why it matters

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The HK G3A4 is the retractable-stock variant of Heckler & Koch's G3 battle rifle, the standard 7.62x51mm NATO infantry rifle of the West German Bundeswehr. It replaces the G3A3's fixed synthetic buttstock with a single-position sliding metal stock that collapses to shorten the weapon for paratroopers, vehicle and armoured crews, and other troops needing a more compact arm without sacrificing the full-power cartridge. Mechanically it is identical to the G3A3: a roller-delayed blowback action - derived from the wartime StG 45(M) and the Spanish CETME - feeding from 20-round detachable box magazines, with a fluted chamber to aid extraction, stamped-steel construction, and the characteristic HK drum-type adjustable rear sight. Entering service around 1974, the G3A4 served alongside the fixed-stock G3A3 throughout the Cold War until the G3 family was superseded in German service by the 5.56mm HK G36 around 2000-2001.

When West German paratroopers and tank crews needed the G3's full-power 7.62mm punch in a package that would fit a jump rig or a turret hatch, the answer was the G3A4 - the same rifle, but with the fixed stock swapped for a single-position sliding steel tube that telescoped the weapon down by nearly 20 centimetres.

Empty weight is higher than the fixed-stock G3A3 (~4.4 kg) because of the heavier sliding metal stock; ~4.7 kg is the commonly cited figure for the G3A4. Collapsed length is roughly 840 mm with the stock retracted versus ~1025 mm extended. Mechanically identical to the G3A3 apart from the stock. Many national G3 users (Turkey, Greece, Pakistan, etc.) fielded equivalent retractable-stock versions.

Specification

Everything measured

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IdentityWhat it is, who built it and when.

Manufacturer
Heckler & Koch
Category
Battle Rifle
Country
Germany
Status
Discontinued
Produced
1974 to 2001
Variant of
Retractable stock

DimensionsAs issued, without a magazine or an optic.

Barrel
450 mm
Overall length
1025 mm
Weight, empty
4.70 kg

ActionHow it cycles, what trips it, and what feeds it.

Action
Roller delayed blowback
Firing mechanism
Hammer fired
Trigger
Single stage
Capacity
20
Magazine
Detachable box

MaterialsEach swatch is the material itself, not a colour chosen to stand for it.

Frame
Steel
Barrel
Steel
Stock
Steel
Finish
Blued

BallisticsFrom the service cartridge, not a handload.

Muzzle velocity
800 m/s
Muzzle energy
3042 J
Effective range
400 m
Maximum range
3000 m
Rate of fire
550 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.

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0 m798 m/s

0200400600800477 m0501002003004005006008001000

Features

What it has

What the record lists as fitted, drawn from the catalogue.

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  • Select fire
  • Roller delayed blowback
  • Retractable stock
  • Stamped steel construction
  • Drum type rear sight
  • Fluted chamber
  • Optics mount

Standing

How it compares

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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.

MeasurementThis firearmMedianPosition
Empty weightAmong 86 7.62x51mm NATO battle rifles4.70 kg4.30 kgHeavier than about 90%
Overall lengthAmong 85 7.62x51mm NATO battle rifles1025 mm1025 mmNear the median
Barrel lengthAmong 87 7.62x51mm NATO battle rifles450 mm458 mmShorter than about 70%
Magazine capacityAmong 87 7.62x51mm NATO battle rifles2020Near the median

Answers

Questions about the HK G3A4

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How much does the HK G3A4 weigh?

The HK G3A4 weighs 4.70 kg (10.36 lb) empty.

What caliber is the HK G3A4?

The HK G3A4 is chambered in 7.62x51mm NATO.

How many rounds does the HK G3A4 hold?

The HK G3A4 holds 20 rounds, fed from a detachable box magazine.

How long is the HK G3A4?

The HK G3A4 is 1025 mm (40.4 in) long overall, with a 450 mm (17.7 in) barrel.

Who makes the HK G3A4?

The HK G3A4 is made by Heckler & Koch (Germany). It was designed by CETME / Heckler & Koch.

When was the HK G3A4 introduced?

The HK G3A4 was introduced in 1974 and discontinued in 2001.

How does the HK G3A4 operate?

The HK G3A4 uses a roller delayed blowback action, and its firing mechanism is hammer fired.

Compatibility

Which parts fit this firearm

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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.

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In service

German Bundeswehr
1974
Bundeswehr airborne and vehicle crews
1974

Provenance

Stockists

Where to buy

Offers link straight to the shop. GunSpec never takes the order.

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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.

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MCP

Ask an assistant about it

The same record, reached the way a person asks for it rather than the way a program does.

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Ask GunSpec

Works with

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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.

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curl --request GET \  --url 'https://api.gunspec.io/v1/firearms/hk-g3a4' \  --header 'X-API-Key: your_key'
Response
{  "id": "hk-g3a4",  "name": "HK G3A4",  "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": "battle-rifle",    "name": "Battle Rifle",    "description": "Selective-fire rifles chambered in full-power cartridges"  },  "country_of_origin": "DE",  "year_introduced": 1974,  "barrel_length_mm": 450,  "weight_empty_g": 4700,  "action_type": "roller_delayed_blowback"}