In short
- BB gun covers three things. An airsoft gun, an air weapon for steel BBs or pellets and, loosely, anything pistol-shaped that goes bang.
- Only airsoft is made for games between people. It fires 6 mm plastic BBs at low energy, at players who wear eye protection.
- CO2 is a power source, not a type. In 6 mm a CO2 pistol is an airsoft gun; in 4.5 mm for steel BBs it is an air weapon.
- The law differs per kind and per nation. You must be 18 to buy any of them, and Scotland and Northern Ireland ask for certificates that England and Wales do not.
Three things people call a BB gun
Search for a CO2 BB gun and the results mix two hobbies. Some of those pistols fire light plastic balls in games between players. Others fire steel balls and are air weapons, for targets only. A few things sold next to them fire nothing at all.
The look does not tell them apart. What comes out of the barrel does.
The three at a glance
| Airsoft gun | Air rifle or air pistol | Blank firer | |
|---|---|---|---|
| What it fires | 6 mm plastic BBs | Lead pellets or 4.5 mm steel BBs | Nothing: a blank cartridge gives noise and flash |
| What it is for | Games between players | Targets and pest control, never people | Stage, film, re-enactment, starting races |
| Energy class | Up to 1.3 or 2.5 joules | Up to 6 foot-pounds (pistol) or 12 (rifle), about 8 and 16 joules | None: no projectile |
| Who may buy it | Adults; realistic colours only with a legal defence | Adults, in person from the shop; a certificate first in Scotland and Northern Ireland | Adults; a realistic one only with a legal defence |
| At an airsoft site | Yes | Never | No |
Airsoft guns: plastic BBs, low power, made for games
What is an airsoft gun? A replica that fires 6 mm plastic balls, called BBs, softly enough for a game between two teams who all wear eye protection. Airsoft guns come as rifles, pistols and revolvers, so a revolver BB gun can be airsoft too.
British law gives airsoft its own definition: a gun designed to fire only small plastic balls, within set energy limits, is not a firearm.
Airsoft pistols in the webshop
All 6 mm, within the limits for Great Britain. In Northern Ireland the line is 1 joule.
In stock, ships right away
GLOCK (Umarex) Airsoft GBB G18C
In stock, ships right away
ELITE FORCE (Umarex) Airsoft CO2 H8R Gen2
In stock, ships right away
GLOCK (Umarex) Airsoft GBB G45
In stock, ships right away
GLOCK (Umarex) Airsoft GBB G17 Gen4Air rifles and air pistols: pellets and steel BBs
An air rifle fires a lead pellet, usually 4.5 mm (.177) or 5.5 mm (.22), for target shooting and pest control; an air pistol does the same on a smaller scale. BASC, the shooting association, cites an estimate of over six million air rifles in England and Wales.
A CO2 BB pistol in 4.5 mm belongs here too. It fires steel BBs, and makers such as Umarex build the same licensed pistols in both calibres. The lever-action Daisy Red Ryder BB gun is the same thing in rifle form. And the metal BB gun? A metal body is fine in airsoft; metal BBs make it an air gun.
Blank firers and other gas pistols
A blank firer looks like a pistol or revolver and fires blank cartridges: a bang and a flash, no projectile. It belongs on a stage or film set, not in an airsoft game.
Gas pistol is the vaguest term of all. In Britain it usually means an airsoft pistol that runs on green gas, filled into the magazine. On the continent it is often a pistol for irritant gas cartridges, and that is a prohibited weapon here.
Which is which?
-
1. It fires a 6 mm plastic BB.
Correct. Not quite.
Small plastic balls at low energy: the only kind used in games between players.
- AAn airsoft gun
- BAn air weapon
- CA blank firer
Show the answer
A. An airsoft gun
Small plastic balls at low energy: the only kind used in games between players.
-
2. It fires a 4.5 mm steel BB from a CO2 capsule.
Correct. Not quite.
CO2 is only the power source. Steel BBs make it an air gun, for targets only.
- AAn airsoft gun, because of the CO2
- BAn air weapon
- CA blank firer
Show the answer
B. An air weapon
CO2 is only the power source. Steel BBs make it an air gun, for targets only.
-
3. It fires a lead pellet.
Correct. Not quite.
Pellets are air weapon ammunition. An airsoft sniper rifle fires 6 mm plastic BBs like any airsoft gun.
- AAn airsoft sniper rifle
- BA blank firer
- CAn air rifle or air pistol
Show the answer
C. An air rifle or air pistol
Pellets are air weapon ammunition. An airsoft sniper rifle fires 6 mm plastic BBs like any airsoft gun.
-
4. It takes a blank cartridge and nothing leaves the barrel.
Correct. Not quite.
Noise and flash only. In law it is an imitation firearm.
- AAn air pistol
- BA blank firer
- CA gas airsoft pistol
Show the answer
B. A blank firer
Noise and flash only. In law it is an imitation firearm.
Power classes side by side
Energy is measured in joules at the muzzle, the open end of the barrel. The older rules for air weapons use foot-pounds (ft lb), and 12 ft lb is about 16.3 joules: more than six times the energy of the hardest-shooting airsoft gun the law allows. Airsoft players also talk in FPS, feet per second. With a 0.20 g BB, 1 joule is about 328 FPS, and the calculator converts the rest.
- airsoft gun in Great Britain; 1.3 J if it can fire automatically
- 2.5 J
- air pistol in England and Wales, about 8.1 J
- 6 ft lb
- air rifle without a firearm certificate in England and Wales, about 16.3 J
- 12 ft lb
- any air or gas gun in Northern Ireland, and an air weapon in Scotland, without a certificate
- 1 J
Source: Firearms Act 1968, section 57A; Firearms (Dangerous Air Weapons) Rules 1969; Firearms (Northern Ireland) Order 2004; Air Weapons and Licensing (Scotland) Act 2015
Joule and FPS calculator
Enter the speed and the BB weight to see the energy. Below is the speed that matches the same energy with other BBs.
Energy
J
The same energy in FPS per BB weight
- 0,20 g
- 328
- 0,23 g
- 306
- 0,25 g
- 293
- 0,28 g
- 277
- 0,30 g
- 268
- 0,32 g
- 259
- 0,36 g
- 244
- 0,40 g
- 232
- 0,45 g
- 219
Calculated with E = ½ × m × v². A site measures with a chrono and sets its own limits; that reading decides.
What the law says for each in the UK
Three mix-ups, straightened out
Myth
An airsoft gun is a kind of air rifle.
Fact
Both use air or gas, and there the likeness ends: plastic BBs at no more than 2.5 joules against lead pellets at up to 12 ft lb. The air rifle limit says nothing about airsoft.
Myth
A CO2 pistol is always an airsoft gun.
Fact
Only in 6 mm. In 4.5 mm it fires steel BBs or pellets and is an air weapon. Check the calibre, above all second-hand.
Myth
A blank firer or gas pistol is free to own, since it fires no bullet.
Fact
A blank firer is an imitation firearm with rules attached, and a pistol made for irritant gas is a prohibited weapon.
Which one do you actually need?
Start from what you want to do
What do you want it for?
Games against other people
An airsoft gun
Any adult can buy a two-tone, an airsoft gun in a bright main colour. A realistic one is sold once the seller can see that you skirmish, usually through UKARA, the player register British shops check.
Airsoft guns in the webshopShooting at targets
An airsoft pistol or an air rifle
For cans and paper at a few metres an airsoft pistol will do. For accuracy at distance you want an air rifle from a gun shop. Check the certificate rules in Scotland and Northern Ireland first.
Targets for airsoftA faithful copy to own
A realistic one needs a legal defence
The law names the purposes: film, theatre, television, a museum, re-enactment or skirmishing at an insured site. Collecting is not among them, so a collector buys a two-tone or takes up the game.
Buying replicas in the webshopSelf-defence
None of them
Nothing here is meant for self-defence, and having any of them with you in public without a reasonable excuse is an offence. Ask your local police for advice on personal safety.
Airsoft law per countryIf the answer is airsoft, play a hire day before you buy. Our webshop ships to the United Kingdom, with import VAT and duties charged on delivery, and asks for evidence that you skirmish when you order a realistic gun. Second-hand works too: check that a listing for used airsoft guns says 6 mm, and start with the listings in the UK.
Before you pay for anything called a BB gun
0 of 5 ticked
Used airsoft guns on the marketplace
What other players are selling today.
Frequently asked questions
Is an airsoft gun the same as an air rifle?
No. An airsoft gun fires 6 mm plastic BBs at no more than 2.5 joules, in games between players. An air rifle fires lead pellets at up to 12 ft lb, about 16 joules, at targets. The first is an imitation firearm in law, the second an air weapon.
Is a CO2 BB pistol an airsoft gun?
Only if it fires 6 mm plastic BBs. A CO2 BB gun in 4.5 mm fires steel BBs and is an air weapon. Plenty of 6 mm airsoft pistols run on CO2 too.
Which of these can I buy without a licence in the UK?
In England and Wales all three at normal power, if you are 18; a realistic airsoft gun or blank firer only where a legal defence applies. Scotland asks for an air weapon certificate for air rifles and air pistols above 1 joule, Northern Ireland for a firearm certificate for any air or gas gun above 1 joule.
Can I use a steel-BB pistol at an airsoft site?
No. Airsoft is played with plastic BBs only, and a steel-BB pistol is an air gun that is never pointed at a person. Keep it for targets and take a 6 mm pistol to game days.
What are the power limits for each type?
Airsoft guns in Great Britain: 1.3 joules if the gun can fire automatically, 2.5 joules otherwise. Air weapons in England and Wales: 6 ft lb for a pistol and 12 ft lb for a rifle. A blank firer fires no projectile, so it has none. In Northern Ireland the line is 1 joule.
What is different in Scotland?
Air weapons are licensed there: an air rifle or air pistol above 1 joule needs an air weapon certificate under the Air Weapons and Licensing (Scotland) Act 2015. An airsoft gun within its legal limits needs none.
Sources
- Guide on Firearms Licensing Law, chapters 2 and 3 Home Office, 12 November 2026
- Air weapons: a brief guide to safety Home Office, 12 November 2026
- Firearms Act 1968, section 57A (airsoft guns) legislation.gov.uk, 12 November 2026
- Firearms Act 1968, section 5 (prohibited weapons) legislation.gov.uk, 12 November 2026
5 more sources
- Firearms (Dangerous Air Weapons) Rules 1969 legislation.gov.uk, 12 November 2026
- Air Weapons and Licensing (Scotland) Act 2015, section 2 legislation.gov.uk, 12 November 2026
- Firearms (Northern Ireland) Order 2004, Schedule 1 legislation.gov.uk, 12 November 2026
- Air rifle code of practice BASC, 12 November 2026
- GLOCK 17 CO2, 4.5 mm BB: technical data Umarex, 12 November 2026
