Going to a close-quarter battle (CQB) at an indoor airsoft field tomorrow night. It's going to be low-light with many dark areas. There is also going to be, at least, one light-out game. A tactical LED flashlight will be helpful. But I haven't had time to shop for one. And I'm not sure I want put my money on one. So here is a jury-rig to get through tomorrow night.
This jury-rig is so simple, you can do it easily if you don't want to spend your money on a tactical flashlight either. All you need is a small LED flash light (same diameter front and back), a roll of hockey tape, and a gun (see photo below).
My APS ASR106 Patriot M4 has a quad rail interface system (RIS), so I was able to fit the LED flashlight snugly between two rails. Stick some hockey tapes between the rails and the flashlight to prevent metal rubbing metal. Then wrap hockey tape around the flashlight and the rails (see photo below). Use a generous amount of tape. You don't want the flashlight to move around while you are turning it on and off in battle.
Note that my LED flashlight was metallic blue. The black hockey tape covered it fully so that little shinning surface could reveal my position. You can use this same trick to cover any colored flashlight.
The flashlight has the on/off toggle button on its back side. When I'm supporting the gun by holding the magazine well, I can easily toggle it with my left thumb. It doesn't obstruct the view down the barrel much at all (see photo below).
By putting it on the RIS on my gun, the silencer blocks the light a bit. But for this application, it's no big deal. You can also move the flashlight forward, by taping it closer to the muzzle, to reduce the blockage.
Now that you have a very inexpensive way of attaching any flashlight to your firearm, you might consider learning how to use it tactically. Take a look at our "Related Links" below for flashlight tactics articles.