Today I noticed that my Tyranitar never missed a stone edge for 4-5 battles straight and the only time I missed was when I got an accuracy drop. Does a sandstorm have anything to do with this or was it just plain out luck?
You just got pretty lucky :P
The only thing sandstorm affects apart from the residual damage is that rock types will get a 1.5 SDef boost under the weather (their Special defense will increase by 50%). Only Rain and Sun affect the power of moves.