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Category
Submachine Gun
Barrel
325 mm
Weight, empty
4.25 kg
Introduced
1938

About

What it is, and why it matters

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The ZK-383 was a Czechoslovak submachine gun designed by the Koucký brothers and built at Zbrojovka Brno. Unusual among submachine guns, it was conceived as a hybrid light-support weapon, with an integral folding bipod, a quick-change barrel, rifle-type long-range sights, and a removable bolt weight that let the user field-adjust the cyclic rate between a controllable ~450-500 rpm and a faster ~700-750 rpm. It fed from a left-side box magazine and saw its largest service with Bulgaria and the Waffen-SS, production continuing through the German occupation.

The ZK-383's cyclic rate could be changed in the field simply by removing a small weight from the bolt, letting a single weapon switch between deliberate supporting fire and a high-rate close assault role.

Sources differ on rate of fire (single 700 rpm vs adjustable dual rate) and production total (~20,000 vs up to ~35,000 across variants); the adjustable dual rate is the gun's signature feature.

Specification

Everything measured

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IdentityWhat it is, who built it and when.

Manufacturer
Zbrojovka Brno
Category
Submachine Gun
Country
Czechoslovakia
Status
Discontinued
Produced
1938 to 1948

DimensionsAs issued, without a magazine or an optic.

Barrel
325 mm
Overall length
875 mm
Weight, empty
4.25 kg
Weight, loaded
4.83 kg

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

Action
Blowback
Firing mechanism
Hammer fired
Trigger
Single stage
Capacity
30
Magazine
Detachable box

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

Frame
Steel
Barrel
Steel
Stock
Wood
Finish
Blued

BallisticsFrom the service cartridge, not a handload.

Muzzle velocity
457 m/s
Effective range
250 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.

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0 m452 m/s

012525037550037 m0501002003004005006008001000

Features

What it has

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

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  • Open bolt
  • Quick detach barrel
  • Removable bolt weight
  • Adjustable rate of fire
  • Folding bipod
  • Left side magazine feed
  • Rifle type adjustable sights

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 201 9x19mm Parabellum submachine guns4.25 kg3.18 kgHeavier than about 90%
Overall lengthAmong 200 9x19mm Parabellum submachine guns875 mm723 mmLonger than about 90%
Barrel lengthAmong 202 9x19mm Parabellum submachine guns325 mm213 mmLonger than about 90%
Magazine capacityAmong 204 9x19mm Parabellum submachine guns3032Holds fewer rounds than about 70%

Answers

Questions about the ZK-383

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How much does the ZK-383 weigh?

The ZK-383 weighs 4.25 kg (9.37 lb) empty and 4.83 kg (10.65 lb) loaded.

What caliber is the ZK-383?

The ZK-383 is chambered in 9x19mm Parabellum.

How many rounds does the ZK-383 hold?

The ZK-383 holds 30 rounds, fed from a detachable box magazine.

How long is the ZK-383?

The ZK-383 is 875 mm (34.4 in) long overall, with a 325 mm (12.8 in) barrel.

Who makes the ZK-383?

The ZK-383 is made by Zbrojovka Brno (Czechia). It was designed by Josef and Frantisek Koucky.

When was the ZK-383 introduced?

The ZK-383 was introduced in 1938 and discontinued in 1948.

How does the ZK-383 operate?

The ZK-383 uses a 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

Bulgarian Army
1940
Waffen-SS
1939
Czechoslovak Army
1938

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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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/zk-383' \  --header 'X-API-Key: your_key'
Response
{  "id": "zk-383",  "name": "ZK-383",  "manufacturer": {    "id": "zbrojovka-brno",    "name": "Zbrojovka Brno",    "countryCode": "CZ",    "foundedYear": 1918,    "website": null,    "logoUrl": null,    "description": null,    "status": null,    "defunctYear": null,    "stateOwned": null,    "makesFirearms": null,    "parentId": null,    "predecessorId": null,    "createdAt": "2026-05-04 12:38:54",    "updatedAt": "2026-05-04 12:38:54",    "version": "c45cfe9ed570296fea2ff63542c2880491f916f83b0234c2eb2aa9fbf313e4c8"  },  "category": {    "id": "submachine-gun",    "name": "Submachine Gun",    "description": "Automatic firearms chambered in pistol calibers"  },  "country_of_origin": "CS",  "year_introduced": 1938,  "barrel_length_mm": 325,  "weight_empty_g": 4250,  "action_type": "blowback"}