FN 303 Mk2
- Category
- Rifle
- Barrel
- 254 mm
- Weight, empty
- 3.14 kg
- Introduced
- 2015
About
What it is, and why it matters
The FN 303 Mk2 is a semi-automatic less-lethal launcher developed by FN Herstal for law enforcement, military and correctional use. It fires .68-caliber (18mm) fin-stabilized projectiles propelled by compressed air from a refillable bottle charged to around 3000 psi, feeding from a 15-round drum magazine at a muzzle velocity of roughly 90 m/s for about 31 joules of impact energy. Payload options include indelible marking paint, washable paint, inert powder and PAVA irritant powder. The Mk2 revision uses a lighter polymer construction and an improved operating system that doubles service life and halves armorer maintenance, delivering accurate suppression at ranges up to about 50 metres with no recoil, noise, flash or pyrotechnics.
The FN 303 traces its origins to a paintball-derived less-lethal concept refined by FN Herstal into a dedicated riot-control launcher, using aerodynamic fin-stabilized rounds to deliver blunt impact and chemical payloads with greater accuracy than shotgun-fired beanbags.
The FN 303 gained notoriety in 2004 when a projectile fatally struck Boston Red Sox fan Victoria Snelgrove during post-World Series crowd control, prompting reviews of less-lethal deployment doctrine.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- FN Herstal
- Category
- Rifle
- Country
- Belgium
- Status
- In production
- Produced
- 2015
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 254 mm
- Overall length
- 744 mm
- Weight, empty
- 3.14 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated
- Firing mechanism
- Externally powered
- Trigger
- Single action
- Capacity
- 15
- Magazine
- Drum
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Polymer
- Barrel
- Steel
- Stock
- Polymer
- Finish
- Matte black
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 90 m/s
- Muzzle energy
- 31 J
- Effective range
- 50 m
- Maximum range
- 100 m
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.
- Compressed air propulsion
- Refillable air bottle
- Fin stabilized projectiles
Picatinny rail
Folding iron sights
No recoil- No muzzle flash
Modular underbarrel mount
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 1,612 rifles | 3.14 kg | 3.50 kg | Lighter than about 70% |
| Overall lengthAmong 1,557 rifles | 744 mm | 1080 mm | Shorter than about 90% |
| Barrel lengthAmong 1,659 rifles | 254 mm | 584 mm | Among the shortest tenth |
| Magazine capacityAmong 1,611 rifles | 15 | 5 | Holds more rounds than about 80% |
Answers
Questions about the FN 303 Mk2
How much does the FN 303 Mk2 weigh?
The FN 303 Mk2 weighs 3.14 kg (6.93 lb) empty.
What caliber is the FN 303 Mk2?
The FN 303 Mk2 is chambered in .68 Caliber (18mm) Less-Lethal.
How many rounds does the FN 303 Mk2 hold?
The FN 303 Mk2 holds 15 rounds, fed from a drum magazine.
How long is the FN 303 Mk2?
The FN 303 Mk2 is 744 mm (29.3 in) long overall, with a 254 mm (10.00 in) barrel.
Who makes the FN 303 Mk2?
The FN 303 Mk2 is made by FN Herstal (Belgium). It was designed by FN Herstal.
When was the FN 303 Mk2 introduced?
The FN 303 Mk2 was introduced in 2015.
How does the FN 303 Mk2 operate?
The FN 303 Mk2 uses a gas operated action, and its firing mechanism is externally powered.
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
- United States Armed Forces
- United States
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/fn-303-mk2' \ --header 'X-API-Key: your_key'{ "id": "fn-303-mk2", "name": "FN 303 Mk2", "manufacturer": { "id": "fn-herstal", "name": "FN Herstal", "countryCode": "BE", "foundedYear": 1889, "website": "https://www.fnherstal.com", "logoUrl": null, "description": null, "status": null, "defunctYear": null, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-02-11 23:44:38", "updatedAt": "2026-02-18 03:43:43", "version": "868b12ac455d24b965edddf486bafb1892f606961311b1ab9907556e3a23b075" }, "category": { "id": "rifle", "name": "Rifle", "description": "Long-barreled firearms designed for accurate shooting" }, "country_of_origin": "BE", "year_introduced": 2015, "barrel_length_mm": 254, "weight_empty_g": 3143, "action_type": "gas_operated"}