Originally Posted By: bubbatime
Originally Posted By: buck91
Specifically, I'm running a Streamlight Polytac LED (88850) on a 5.56 carbine.
A dedicated weapon light has springs on both ends of the batteries. The springs act as shock absorbers for the batteries during recoil. I personally wont use a flashlight that doesn't have springs on both ends. Its a $40 flashlight, so if you kill it, its not a big deal.
Might want to look at getting a better light. The Streamlight Rail Mount or TLR1 can be found in the $100 range. A Malkoff MD2 would likely fit in your same mount and is a bulletproof light, also about $100.
I know the PT is only a $40 light but it seems to be well reputed. Lifetime warranty, weapons rated, sprung on both terminals. Not to mention a pretty top notch company (ie: all of our lights at the FD are Streamlight...currently). Sure, it lacks some of the "feel" of higher end lights but I'm not convinced its "just a $40 light" so to speak.
Anyways, sounds like its worth leaving it on if for no other reason than to test out the durability.