Use JBM and run a velocity of 3360 fps and a BC of 0.8. Check total drop at 1000 yards for -30 degrees and for +30 degrees.
Augustus, the take away message from the linked post of Shawn Carlock's is that you multiply the cosine times the drop not the distance. And if you have it, that a good PDA ballistics program is even more accurate than the cosine times the drop method.
Consider that the density of air decreases in the uphill direction and that drag on the bullet is decreasing more and more as the bullet flies further uphill thus even though gravity is slowing the bullet down, the air resistance is easing up and letting the bullet keep its speed.
Going downhill, gravity is speeding up the bullet but the air is getting more and more dense the further downhill the bullet goes and slowing the bullet down. Thus in the downhill direction, the greater density is reducing the speed increase by gravity. However, being as the effect of gravity is two to four times greater then the effect of density, the gravity effect is more important than the density. And neither is really important until you get out into the the original distance you specified of 2K.
Now then, it is possible that I have something backwards being as I was trained to work with a pencil, paper and sliderule and working with a computer sketch pad does not come natural to me.
The Smokin Fur Rifle Club