I read an article written by an Army SF guy that did multiple tours in Afghanistan in both the summer and winter months. I believe it was in SWAT magazine. He said they would zero their EOTechs before leaving the states then again when they got in country.
They would notice the zero shift when they would get there in late summer/early fall and their deployment went into the winter. Or if they got there in the winter and their deployment went into the spring/early summer.
In other words, extreme temperature spreads. Once they knew about the zero shift issue they just checked them more often and re-zeroed accordingly. The weather would stay the same for a long enough period of time that they could go do their thing without worrying about it.
NYH1.
***Edited to add, I'm an Aimpoint guy. However, I'd use a EOTech without worry.***
Last edited by NYH1; 11/27/17.
