*The M-3 Tactical Illuminator*
By: BullDog6
24 January 2003

Many feel that a weapon mounted light can be a significant advantage in an urban tactical scenario.  My requirements were to have a 6 volt light that mounts cleanly and easily on both a Beretta 92F pistol and a AR-15 carbine.  I carry the pistol on a daily basis, and want to mount the light on the pistol when I get home, keeping the weapon by my bedside.  I would mount the light on the carbine if a tactical situation develops where I need it.

After some online comparison shopping, I decided to purchase an M-3 Tactical Illuminator manufactured by Streamlight (Insight Technologies).  In the world of tactical lights, there really are no cheap options.  Surefire lights have a good reputation, but tend to be pricey and I didn't see a mounting option I particularly liked for my situation.  The TACM III lights used a wired remote switch, and a magazine base light mount, which seemed like a draw back.

The M-3 Light

 The M-3 is the simplest of the lights offered by Streamlight.  (The M-6 includes a laser with the light)  The light uses two 123 type 3v batteries that slip in at the rear of the light, and covered with the switch assembly.  The switch is a lever type assembly with levers on both sides of the light.  Moving the lever in one direction provides a momentary on, and in the other to a constant on.  The lamp assembly is adjustable for focus by turning the housing.  The mount portion is molded into the body of the light.  A spring loaded bar locks into the notch on the weapon side of the mount.  To remove the light, lift up on the bar, and slide the light forward off the mount.
Comparison of the light output of the M-3 (center top), a Mini-mag type  2AA light (bottom left) and a 3 Cell full size Mag lite (bottom right)  Batteries were weak in the large Mag lite, so the  light isn't as bright as it could be.

Adaptor Mount for Beretta 92F

Light mount on the Beretta 92F

The pistol mount was even easier to install.  The M-3 light is designed to fit on Glock pistols with built in rails.  My Beretta didn't have those rails, so an adapter was necessary.  The adapter is also made of the nylon type plastic material, which feels quite strong and rugged.  It slipped snuggly into place over the front of the trigger guard and forward portion of the lower receiver.  A metal clip slipped behind the trigger guard, then a tension screw was tightened down.  It is definitely a solid mount, with no movement at all.  The light slips right in place, and can be removed easily too.

The position of the switch on the pistol requires a slightly different position of the left hand in order to reach the switch with your thumb.  The weight of the light is evident on the pistol, but not to any significant degree.


Mount for the AR-15
 I started with attaching the mount to the AR-15 handguard.  First, I strapped the light in place to decide on the best position.  The recommendations I have seen are underneath, or at the 10 o'clock or 2 o'clock position on the upper handguard.  I chose the 10 o'clock position (as seen from the rear) because it allowed me to use my thumb activate the light in what seemed to be the most natural motion.  Installing the mount was relatively straight forward.  After removing the handguard, I had to position the mount where I wanted, and drill pilot holes through the screw holes in the mount.  I finished drilling the holes through the plastic and aluminum of the handguard, then enlarged the holes in the aluminum shield to accomadate the nut plate.  The hex head screws fit in just fine, and tightened up well.  The only minor problem seems to be in removing the light once mounted.  The mount is very tight, and takes some effort to slide the light off.  I think this will loosen up with use, and since the mount is made of a nylon material, it can be easily shaved down to make it easier.

Light mount on the AR-15 Carbine.

On the carbine the position of the switch is quite easy to trigger with your thumb.  A possible concern is that it might accidentaly be triggered.  There is no lock on the switch to prevent that.  The M-3 weighs little, and is not noticeable on the heavy barrel carbine I have.  

The beam put out by the light is strong, bright, and nicely dispersed.  Its not a strong sharp beam, but more of a wide area flood.  In tests in a darkened room, triggering the light puts a strong light at the center of the beam, and a strong enough glow all around that lets you see well to the sides and even somewhat to the rear.


With any piece of equipment, its only as good as you use it.  A light is no panacea of the problem of darkness in a tactical situation, but a good mounted light is much easier to manipulate than a seperate flashlight and weapon.  I ordered the light, rifle and pistol mounts from the Arizona Gunrunners website.  They arrived less than two weeks later, although the pistol mount was sent seperately a couple of days after the rest.

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