Elevation for Confused Cats

Or sheep. Shooting uphill or downhill, just work out what the horizontal range is and use that.

Too confusing for your cat: US Army Field Manual FM 3-05.222 "Special Forces Sniper Training and Employment" Table 3-9. "Compensation Factors Used When Firing From a Given Angle" "Percent of Slope Angle Up or Down (Degrees)" = 45 "Multiply Range by" = 0.7 (eyes left for diagram).

For nerd cats: "Multiply Range by" is the Cosine of the Slope Angle. They actually make Cosine spirit levels to stick on you rifle so you can see the "Multiply Range by" automatically.

But, this isn't correct: http://www.gun-blog.com/2011/11/cosine-rules-for-uphill-downhill.html