Is there a scientific reason crosshairs are set vertical?

[W.R.Buchanan]

I always thought it was because the wind blows from side to side and gravity makes things go down.

Scientifically speaking,,, This pretty much covers it. Although I see no need for the Smilie: This is pretty much common sense since the two axis' of deviation you must deal with are vertical and Horizontal.

I know of no Reticle other than a Red Dot that doesn't have an obvious Vertical/Horizontal orientation.

Plus that what happens if you just need to hold over the target to compensate for Drop. Without the vertical line for reference you invariably will introduce a windage error into your sight picture.

My .02

Randy

[Jim_P]

The Smile was because - IMHO - the answer was so obvious the question had to be a fake...