I thought I would share a video I took last weekend from Menard County Texas. I know it's rifle season, but myself and brother bow hunt all season. We sometimes sit together in ground blinds or pop-ups and just spend quality time together while videoing each others hunts. I have seen several discussions on the best 'aim point' while bow hunting. In the end, it always depends on a number of factors like distance, bow speed, the deer's state of relaxation at the time etc. I wanted to show this video to visually show how a deer reacts when shot (or shot at). What I always find incredible are the deers reaction times, and how far they drop when springing out of a dead still stance. This video was on my iPhone so it's not the greatest of quality but it does show the reaction.

http://www.youtube.com/watch?v=kO3uqJ7OQVo

In most cases people do miss high. Especially 15 ft in air

Yes, that is another fact people seem to forget. The higher you are from your target, the higher you will hit your target because the force of gravity is reduced for every degree of angle as you get higher.

Force of gravity is pretty much consistent...no matter how high you go.

As you go higher, it is important to use the horizontal distance, not the "actual" distance. Basically, how far is the deer from the base of the stand, not the distance your range finder says from where you are sitting. At 15', the difference is negligible.

I do not allow for the drop of an animal. I aim where I want to hit and try not to shoot at an overly alert animal.

Your topic brings up an interesting point concerning those bow hunters that shoot out to 40 and 50 yards though...

Aim ...place your pin where you want the arrow to hit
Aim small...Hit small

If you use a good range finder that also has the angle calculation you will see that there is basically no differance in yardage from base of tree and when sitting in the stand at this distance

"Force of gravity is pretty much consistent...no matter how high you go."

OK, this is 100% true.... I should have said "the effects of the force of gravity..."

The effects of the force of gravity are the same and remain the same through the flight of an arrow.

For instance, if I aim at a point perfectly horizontal at 20 yards and gravity will cause my arrow to drop 2" at that distance, then take a shot at the same horizontal distance, but at at a target that is 15' below my starting point...the drop in the arrow flight, caused by gravity, is still 2".

I always aim where I want to hit on my place. But.....that goes out the window if your hunting day lease matrix moving ninja deer! It depends on the place and how educated the deer are imo...I was at a day bow lease last yr and I aimed like I always do at a doe at 18 yards,sh%t ...I missed her cause she dropped down to dirt. The next day same situation , I aim a foot below heart on a doe and hit here perfect behind shoulder! So...if your on your lease aim where you plan to hit. But, some educated day lease deer may need some adjustments.lol.

I know it is different with a rifle, but I have hunted a lot from ridges where the deer is at a significantly lower elevation. I try to aim higher, attempting to visualize the bullets travel through the deer- aim lower when deer is above me. I have seen friends forget about the angle of the bullet in the heat of the moment and looking at the animal through scope at magnification, and put cross-hairs low behind the shoulder like they would on a more horizontal shot and just catch the bottom of the onside lung, makes for a long recovery- if not lost deer. Taking the deer's reaction out of the equation, is there a reason for a different thought process with a bow? (I am not an experienced bow hunter)

Taking reaction of deer out of equation, with a bow or rifle aim lower than normal if deer is up higher on a ridge and same if deer is lower down in gulley ,you must aim low. The amount depends on the angle.

Now... this is just working it out in my head... then trying to make some bullet points.

1. A bullet or arrow will travel on an arch type path when shot parallel to the ground.

2. Gravity starts working on it as soon it leaves the bow/firearm with the effect of pulling the projectile towards the center of the earth.

It would seem to me that as shooter starts aiming more towards the center of the earth (ie-downhill), then that arch will not be as pronounced compared to shooting towards the horizon.

My hypothesis: a hunter will have to aim low when shooting down steep grades.

Correct . As well as aim low when shooting up steep grades, as hard as it is to comprehend its true.