Mechanics behind a red dot site....

[HECKLERKOCHG3]

I dropped my ak on accident on hard ass concrete and it landed directly on the simmons 30mm red dot. I want to know how durablr the simmons is or any red dot and how exactly the red dot scope works. Internal pieces etc.
I had an M68 in Afghanistan and the damn thing went out on me out of nowhere. I took very good care of my M4 so the red dot sure as hell didn't go out due to force.

[Wirblewind]

Durability varies with manufacturer and model. Generally the Aimpoint and Trijicon sights have the rep of being the most durable.

Here is a good description of the principle.

http://ourworld.compuserve.com/homepages/Dreyer_infonet/dotsight.htm