FB Grot C16
- Category
- Assault Rifle
- Barrel
- 406 mm
- Weight, empty
- 3.70 kg
- Introduced
- 2018
About
What it is, and why it matters
The FB Grot C16 is a Polish 5.56x45mm NATO select-fire assault rifle in conventional (classic) layout, the standard-issue service rifle of the modular MSBS Grot family built by Fabryka Broni Lucznik-Radom. It uses a short-stroke gas-piston system with a rotating bolt, feeds from 30-round STANAG magazines and fires in semi-automatic, three-round burst and fully automatic. The modular receiver shares its upper with the bullpup B16, switching layout by swapping the lower.
Grot means 'spearhead' in Polish - and the rifle is genuinely two guns in one: the same upper receiver bolts onto either a conventional or a bullpup lower, letting a soldier reconfigure the weapon's whole silhouette in the field.
C16 = conventional configuration; the B16 is the bullpup sibling built on the same upper receiver. Replacing the wz. 96 Beryl in Polish service.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Fabryka Broni Lucznik - Radom
- Category
- Assault Rifle
- Country
- Poland
- Status
- In service
- Produced
- 2018
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 406 mm
- Overall length
- 980 mm
- Width
- 65 mm
- Weight, empty
- 3.70 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated short stroke
- Firing mechanism
- Rotating bolt
- Trigger
- Single stage
- Capacity
- 30
- Magazine
- Detachable box
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Aluminum
- Barrel
- Steel
- Stock
- Polymer
- Finish
- Anodized
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 890 m/s
- Effective range
- 500 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.
Modular design
Telescoping stock
Picatinny rail
M lok handguard
Ambidextrous controls
Free floating barrel
Stanag magazine
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 158 5.56x45mm NATO assault rifles | 3.70 kg | 3.60 kg | Heavier than about 60% |
| Overall lengthAmong 156 5.56x45mm NATO assault rifles | 980 mm | 920 mm | Longer than about 80% |
| Barrel lengthAmong 157 5.56x45mm NATO assault rifles | 406 mm | 449 mm | Shorter than about 70% |
| Magazine capacityAmong 158 5.56x45mm NATO assault rifles | 30 | 30 | Near the median |
Answers
Questions about the FB Grot C16
How much does the FB Grot C16 weigh?
The FB Grot C16 weighs 3.70 kg (8.16 lb) empty.
What caliber is the FB Grot C16?
The FB Grot C16 is chambered in 5.56x45mm NATO.
How many rounds does the FB Grot C16 hold?
The FB Grot C16 holds 30 rounds, fed from a detachable box magazine.
How long is the FB Grot C16?
The FB Grot C16 is 980 mm (38.6 in) long overall, with a 406 mm (16.0 in) barrel.
Who makes the FB Grot C16?
The FB Grot C16 is made by Fabryka Broni Lucznik - Radom (Poland). It was designed by Adam Gawron.
When was the FB Grot C16 introduced?
The FB Grot C16 was introduced in 2018.
How does the FB Grot C16 operate?
The FB Grot C16 uses a gas operated short stroke action, and its firing mechanism is rotating 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
- Polish Armed Forces
- 2017
- Polish Territorial Defence Force
- 2017
- Armed Forces of Ukraine
- 2022
Provenance
Confidence in this record
74%
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/grot-c16' \ --header 'X-API-Key: your_key'{ "id": "grot-c16", "name": "FB Grot C16", "manufacturer": { "id": "fb-radom", "name": "Fabryka Broni Lucznik - Radom", "countryCode": "PL", "foundedYear": 1922, "website": "https://fabrykabroni.pl", "logoUrl": null, "description": null, "status": "active", "defunctYear": null, "stateOwned": null, "makesFirearms": true, "parentId": null, "predecessorId": null, "createdAt": "2026-02-11 23:44:40", "updatedAt": "2026-02-18 03:40:45", "version": "e6e5937015da3c7035ea07c9409d7500b412e3d7efc6f4185883ba6d163a9be8" }, "category": { "id": "assault-rifle", "name": "Assault Rifle", "description": "Selective-fire rifles chambered in intermediate cartridges" }, "country_of_origin": "PL", "year_introduced": 2018, "barrel_length_mm": 406, "weight_empty_g": 3700, "action_type": "gas_operated_short_stroke"}