I was listening to the Ben Stoeger podcast "Practical Shooting After Dark, Episode 82" and he and one of his guests were discussing how their pistol mounted open emitter red dot sight (SRO I believe) was basically unusable due to dust/silt/sand on the emitter. the only way to prevent it was to cover or bag the dot topped pistol.
I found that particular failure/trouble vector especially interesting considering that in the spring and fall I live in dust storm central.
Comments? Experience?
I'm going to go back and listen again because I was driving at the time and only halfway paying attention to the discussion.
The sand issue discussion starts at around 9:50 .