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If you're running a short barrel they should fit the bill. I haven't used one but I would be worried about the shock to the lamp head. Maybe an LED lamp would be more shockproof.
I'm sure some like Beeson could comment intelligently on the subject.
I bought a nice little rail that fits over the end of the mag tube and is held in place by the mag tube cap...it's was pretty cheap and works well...can't seem to remember who makes it....