Berezin UB
- Category
- Machine Gun
- Barrel
- 890 mm
- Weight, empty
- 21.45 kg
- Introduced
- 1941
About
What it is, and why it matters
The Berezin UB (Universalny Berezina) is a Soviet 12.7x108mm gas-operated, belt-fed aircraft machine gun designed by Mikhail Berezin and introduced in 1941. Developed from the earlier synchronized BS design, the UB became the standard Soviet heavy-caliber aircraft machine gun of World War II, arming fighters such as the Yak, La and Il series. It was produced in three principal forms: the UBK for wing mounting, the UBS for synchronized fuselage installation firing through the propeller arc, and the UBT for flexible turret defense. Its high rate of fire and powerful cartridge made it one of the most effective aircraft guns of its class during the war.
Mikhail Berezin began designing his aircraft machine gun in 1937, and the weapon was accepted into Soviet service in 1939 as the synchronized BS before the improved UB appeared in April 1941. It replaced the older ShKAS-derived heavy guns and remained the backbone of Soviet fighter armament throughout the Great Patriotic War.
The synchronized and wing variants were pneumatically charged, while the turret variant was manually charged. Roughly 130,000 units were produced between 1941 and 1945.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Izhevsk Machine Building Plant (Izhmash)
- Category
- Machine Gun
- Country
- Soviet Union
- Status
- Discontinued
- Produced
- 1941 to 1947
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 890 mm
- Overall length
- 1347 mm
- Weight, empty
- 21.45 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated
- Firing mechanism
- Hammer fired
- Magazine
- Belt
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Steel
- Finish
- Parkerized
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 814 m/s
- Muzzle energy
- 16000 J
- Effective range
- 1000 m
- Maximum range
- 3500 m
- Rate of fire
- 1050 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.
No load solved for this record yetThe flight path is computed from a cartridge and a bullet. This record has no ammunition filed against its chambering, so there is nothing to solve.
Features
What it has
What the record lists as fitted, drawn from the catalogue.
Belt fed
Air cooled- Aircraft mounted
- Pneumatic charging
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 | 21.45 kg | 10.50 kg | Heavier than about 80% |
| Overall lengthAmong 260 machine guns | 1347 mm | 1156 mm | Longer than about 80% |
| Barrel lengthAmong 257 machine guns | 890 mm | 605 mm | Longer than about 90% |
Answers
Questions about the Berezin UB
How much does the Berezin UB weigh?
The Berezin UB weighs 21.45 kg (47.29 lb) empty.
What caliber is the Berezin UB?
The Berezin UB is chambered in 12.7x108mm.
How long is the Berezin UB?
The Berezin UB is 1347 mm (53.0 in) long overall, with a 890 mm (35.0 in) barrel.
Who makes the Berezin UB?
The Berezin UB is made by Izhevsk Machine Building Plant (Izhmash) (Russia). It was designed by Mikhail Berezin.
When was the Berezin UB introduced?
The Berezin UB was introduced in 1941 and discontinued in 1947.
How does the Berezin UB operate?
The Berezin UB uses a gas operated 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
- Soviet Air Forces
- 1941
- People's Liberation Army Air Force
- China
- Korean People's Army Air Force
- North Korea
Provenance
Confidence in this record
82%
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/berezin-ub' \ --header 'X-API-Key: your_key'{ "id": "berezin-ub", "name": "Berezin UB", "manufacturer": { "id": "izhmash", "name": "Izhevsk Machine Building Plant (Izhmash)", "countryCode": "RU", "foundedYear": 1807, "website": "https://kalashnikovgroup.ru", "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": "9758b272c4082a5b8a3cb74546ec83f848df13e131b9700224561e9ac6c8647a" }, "category": { "id": "machine-gun", "name": "Machine Gun", "description": "Fully automatic firearms for sustained fire" }, "country_of_origin": "SU", "year_introduced": 1941, "barrel_length_mm": 890, "weight_empty_g": 21450, "action_type": "gas_operated"}