For most UK long guns, the best weapon light is a rail-mounted light with around 20,000 cd or more and a remote pressure switch. In our range that means the SureFire Scout Light Pro series or the Streamlight TLR RM 2 and ProTac 2.0 Rail Mount. For maximum reach, choose a high-candela "Turbo" or "HP" model. For a pump shotgun, the Streamlight TL-Racker forend is the tidiest answer.
Lumens get the attention, but candela and the switch decide how well a weapon light works. Below: what the numbers mean, the picks by job with manufacturer-published figures, and the fitting points that trip people up.
Key takeaways
- Candela, not lumens, sets reach: under ANSI FL1, throw in metres is 2 × √candela.
- A rifle light is only as good as its switch; a remote pressure or tape switch under the support hand beats a tailcap you have to reach for.
- SureFire's Turbo Scout Lights publish up to 100,000 cd; Streamlight's ProTac 2.0 Rail Mount HP publishes 85,000 cd.
- Multi-fuel lights often reach their headline figures only on their rechargeable cell, so check the CR123A figures too.
- In Great Britain most handguns are prohibited, so "pistol" lights here mostly go on carbines, shotguns and airsoft replicas.
Lumens vs candela: what matters
Lumens measure total output, which is how much area the light floods. Candela measures peak beam intensity, which is how far the beam reaches. Two 1,000-lumen lights can throw 213 m (SureFire X300U-A, 11,300 cd) and 510 m (Streamlight TLR-1 HP, 65,000 cd), depending on how the optic shapes the beam.
As a rule of thumb, a balanced 10,000 to 20,000 cd beam suits close work in barns, yards and woods, where spill helps you see the whole scene. Across open ground you want 40,000 cd or more. Our lumens vs candela chart turns any candela figure into a throw distance.
Our picks by job
All figures are the manufacturers' own, on the high setting. Where a light runs on two battery types, the higher figure is on the rechargeable cell.
| Job | Light | Lumens | Candela | Battery |
|---|---|---|---|---|
| Rifle, all-round | SureFire M640U Scout Light Pro | 1,000 | 11,300 | 2 × CR123A |
| Rifle, maximum throw | SureFire M640DFT Turbo Scout Light Pro | 700 (600 on CR123A) | 100,000 (90,000) | SF18650 or 2 × CR123A |
| Rifle, rechargeable | Streamlight ProTac 2.0 Rail Mount HP | 2,000 | 85,000 | SL-B50 pack |
| Rifle, value with remote switch | Streamlight TLR RM 2 System | 1,000 | 22,000 | 2 × CR123A |
| Compact rail | SureFire X300U-A | 1,000 | 11,300 | 2 × CR123A |
| Compact rail, high candela | Streamlight TLR-1 HP-X | 1,300 (1,000) | 77,000 (53,000) | SL-B9 or 2 × CR123A |
| Pump shotgun | Streamlight TL-Racker | 1,000 | 20,000 | 2 × CR123A |
Rifle lights
Long-gun lights mount to a Picatinny or M-LOK section on the handguard and are best run from a remote switch. SureFire's Scout Light Pro range is the benchmark for build and beam quality. The M640DFT publishes 100,000 cd on its rechargeable SF18650 cell, which works out at about 632 m of ANSI throw (SureFire M640DFT). Streamlight's TLR RM 2 comes as a System kit with a remote pressure switch in the box, and the ProTac 2.0 Rail Mount HP puts 2,000 lumens and 85,000 cd on a USB-C rechargeable pack (Streamlight ProTac 2.0 Rail Mount HP).
If the rifle is used for foxing or other night vermin work, our guide to optics for fox and night vermin control covers lamping and the rules that apply.
Compact rail lights
The SureFire X300 and Streamlight TLR-1 and TLR-7 families were designed for pistol accessory rails, but they fit any 1913 rail. On a British straight-pull, a pistol-calibre carbine or a shotgun with a short rail section, a compact light keeps weight off the muzzle. The X300U-A publishes 1,000 lumens and 11,300 cd (SureFire X300U-A). The TLR-1 HP-X is the throw-biased alternative. If the TLR model names are confusing, our Streamlight TLR comparison guide decodes them.
Shotgun lights
A shotgun's moving forend makes clamp-on lights awkward. The TL-Racker replaces the forend of a Mossberg 500/590 or Remington 870, with a full-length ambidextrous switch. Streamlight quotes 1,000 lumens, 20,000 cd, 283 m, 1.5 hours on two CR123As and IPX7 (Streamlight TL-Racker). Choose the version for your gun.
UK note
Most handguns are prohibited in England, Wales and Scotland under section 5(1)(aba) of the Firearms Act 1968, inserted by the Firearms (Amendment) Act 1997 (legislation.gov.uk). That provision does not cover firearms at least 60 cm long with a barrel of at least 30 cm, such as long-barrelled pistols. Northern Ireland is governed by the Firearms (Northern Ireland) Order 2004, which has no equivalent length-based ban. In Britain, lights sold as "pistol" lights therefore mostly go on long guns with a rail, long-barrelled pistols and airsoft replicas. A weapon light itself is not a firearm; our licence guide for scopes, red dots and torches sets out the framework. Confirm anything specific with your firearms licensing department.
How many lumens do you need?
- Barns, yards and indoors: 300 to 1,000 lumens with a broad beam. More output in a confined, pale-walled space bounces back at you.
- General-purpose rifle: 1,000 lumens or so with 20,000 cd or more, which covers indoor-to-field use.
- Open ground: 50,000 cd and up from a Turbo or HP model. The lumen figure hardly matters here.
Switches and mounting
On a rifle or shotgun, the light should turn on without you changing your grip. That usually means a remote pressure or tape switch under the support hand, routed along the handguard. SureFire sells its remote switches separately, including the ST07 tape switch and the DS07 and SR07 dual switches, all in weapon light accessories. Streamlight's TLR RM System kits include a remote pressure switch in the box. Check the mount interface (Picatinny, M-LOK or both) against your handguard before ordering.
Rechargeable, CR123A or both?
Most current lights are either USB-C rechargeable or multi-fuel, which means they run on a rechargeable lithium-ion cell or on CR123A primaries. Multi-fuel is the most flexible arrangement, but the output often drops on primaries. The TLR-1 HP-X falls from 77,000 cd to 53,000 cd on CR123As (Streamlight TLR-1 HP-X). Rechargeable against CR123A is a trade of running cost and output against shelf life and cold-weather performance.
Our top picks at a glance
- Best rifle light: SureFire M640U or M640DFT Scout Light Pro.
- Best value rifle kit: Streamlight TLR RM 2 System.
- Best high-candela thrower: SureFire M640DFT, or Streamlight ProTac 2.0 Rail Mount HP if you want USB-C charging.
- Best compact: SureFire X300U-A or Streamlight TLR-1 HP-X.
- Best for pump shotguns: Streamlight TL-Racker.
Working to a budget? Best weapon lights under £250 covers the half of the range that sits below that line. For the brand question, read SureFire vs Streamlight.
Frequently asked questions
How many lumens do I need for close work?
Around 300 to 1,000 lumens with a broad beam is plenty inside 25 m (27 yd). Past that, more lumens mostly adds glare off nearby surfaces.
Lumens or candela: which matters more?
Candela, for anything beyond close range, because it sets how far the beam reaches. Lumens matter for how much of the scene you can see at once.
Do I need a pressure switch?
On a rifle or shotgun, a remote pressure or tape switch is strongly recommended, because it lets you work the light without shifting your grip. Many Streamlight System kits include one, and SureFire sells them separately.
Can I put a pistol light on a rifle?
Yes, if the rifle has a 1913 Picatinny section, since most full-size and compact pistol lights clamp to a 1913 rail. Micro lights cut for a specific pistol frame will not fit.
Shop this guide
- Weapon lights: the full rail, forend and compact range.
- SureFire weapon lights: Scout Light Pro and X300 series.
- Streamlight TLR weapon lights: the broadest choice of hosts and outputs.
- Weapon light accessories: remote switches, tailcaps and spares.
