​Selecting a Flashlight for Your Firearm

​Selecting a Flashlight for Your Firearm

Posted by Alice Jones Webb on Aug 19th 2019

The ability to clearly identify a potential target in a tactical or self-defense situation is crucial for safety and effectiveness. While handheld flashlights are the traditional method of illuminating dark surroundings, a weapon-mounted flashlight holds several benefits over handheld models.

A weapon mounted flashlight:

● Allows you to keep both hands on your weapon to maintain maximum control.

● Can free your support hand when necessary, allowing you to complete other tasks like opening doors

● Disorients attackers, giving you precious seconds to assess the threat and put rounds on target.

● Acts as a counterweight, reducing felt recoil and muzzle climb, increasing speed and accuracy of follow-up shots.

Choosing a Weapon Light

Advances in LED (light emitting diode) technology and battery efficiency have made modern mounted flashlights smaller, brighter, and more lightweight. However, not all flashlights are created equal. Here are a few things to consider when choosing a flashlight to mount on your firearm.


While brighter may seem better, this isn’t always the case. As a shooter, you want enough light to clearly identify your target and your immediate surroundings. However, too much light can have detrimental effects on your own night vision.

In addition to the negative affects a bright light can have on vision, a brighter light generally requires more battery power. Brighter lights typically have either 1) a shorter battery life or 2) are excessively heavy, negatively affect the maneuverability of your weapon.

What are lumens?

Lumens (lm) are internationally accepted units used to measure the amount of light produced by a light source. Most light sources, including indoor lamps, flashlights, and even streetlights, will have their brightness measured in lumens. Light output ranges from a dim 20 lumens (common on a typical book light) to 20,000 lumens (often used in floodlights).

How many lumens do I need?

This question is often debated in gun circles. While some shooters adamantly believe they must have “all the lumens,” there are many reasons brighter isn’t always better. How many lumens your flashlight needs largely depends on the intended use of your weapon and your mounted light.

If you use your firearm for home defense, a dimmer light may be the best option. It takes less light to brighten indoor areas than outdoor areas. This is why we use reading lamps to light our living room and flood lights to brighten our yards. Also, a brighter light in a home defense situation has the potential to bounce off mirrors and even walls painted in light colors. This could disrupt your night vision and leave you temporarily stumbling in the dark. For indoor, home defense situations, 90 to 150 lumens should provide enough light to effectively identify a home intruder.

If you will be using your weapon and your flashlight outdoors, you may want to consider something brighter.

Light Beam

Most weapon-mounted lights will have one of two main beam configurations.

Flood Beam - Also known as a wide-angle beam, this configuration focuses light into a wide cone with uniform light distribution through the width of the beam. A flood beam creates a more natural lighting condition and increases visibility in the periphery of the beam. This wide angle has a limited range and can make long-range target identification more difficult.

Spot Beam - A spot beam is narrow and focused, maximizing the “reach” of your light. This type of beam provides better visibility at longer ranges but sacrifices close quarter peripheral vision.


You want your weapon light to be powered by a reliable source. Having your batteries die in the middle of a tactical, self-defense, or hunting situation could be disastrous. Rechargeable, CR123, 18650, and AA batteries are common power sources for weapon-mounted lights.

Look for a flashlight with a compact, lightweight power source with a long shelf life.


A weapon-mounted flashlight must be rugged. Your light needs to withstand occasional impact and rough handling. However, the internal electronics of your weapon-mounted flashlight must be designed to endure the recoil of a handgun, rifle, or shotgun. In addition, the lens must be sturdy enough to weather high-temperature muzzle blast and fouling without sacrificing light quality.

There are plenty of advantages to adding a mounted flashlight to your tactical, self-defense, or hunting set-up. As with all shooting accessories, it is important to practice shooting with your attached flashlight so you can acclimate to any changes in the feel or function of your weapon.

Monstrum offers several compact, lightweight LED flashlights that can be easily mounted on your long gun or sidearm. All are constructed of durable aircraft grade aluminum, making them tough enough to withstand repeated use in practically any shooting application. View Monstrum flashlights here.