Kelly/KY

There is margin distance difference from the average height of a treestand, but I agree with Kodiak, for those hunting out west from perhaps extreme angles, it would be helpful. I'm a gadget person, unfortunately, and bought one. I like it, but for most of my hunting it shouldn't be much of an aid. So, if you primarily hunt deer from stand and want to be penny wise, there are plenty of cheaper less complicated models out there.

The formula for calclulating the distance is a simple geometry problem a-sqared + b-sqared = c-squared, where a if the height and b is the distance from the base of the tree or stand.Convert the height to yards, square it then add the square of the 20 yards from the base then take the sqare root of the sum. That confused even me, so may it's not that simple...lol Rob's calculations are correct in the above post. Good luck

Kelly

kwilson16

Distance is not the issue.

The issue is the difference in angle between the arrows flight path and gravity. On level ground, gravity is acting perpendicularto the arrows flight path. From an elevated postion, this angle becomesless and reduces gravity's effect.

For a demo, hold a limber fishing rod straight level and note the bend caused by gravity. Hold the rod downward (or upward)at any appreciableangle and the bend will be less.

This is why you must hold under on uphill as well as downhill shots. Pythagoras will get you close buthe won't help you undestand what's happening to your arrow in flight and this clever Greek'serror grows larger at steeper angles.

Rob/PA Bowyer

That is absolutely, positively FALSE! I've shot competitive archery for more years than I can remember, once you have the distance you aim dead on, never high or low or you will go high or low. Let's say you have a 3D target at 20 yards, if you bend at the waist you should put your 20 yard pin dead center of the 10 ring and if you execute a good shot, you will nail it dead center.

Same uphill....I've done it too many years.

Remember, the fraction it takes an arrow to travel said distances, gravity has very little effect on the arrow comparing shooting level, uphill or downhill. Distance is distance is fractions of a second.

The only reason to hold low on uphill shots is path of the arrow through the animal, same downhill, aim for the exit hole.

War Eagle

First off let me thank you for giving me something to do this afternoon. The engineer in me wouldn't leave this one alone and I have spent the last two hours with a MS Excel combating this problem.

All of the calculations discussed above are correct. However, from what I got out of their literature, they are displaying "ballistic" range and not the levelized range. The ballistics calculationsare done based upon a user setup. The archery calculation can use one of three pre-programmed values with the worst case being an initial arrow speed of less than 215 feet per second and the fastest being over 250 feet per second. The Leupold exampleuses the "TBR A" setting which is thebelow 215 ft/s calculations.

I think we all agree that a 40 yard target from 20 feet high is closer to 39 yards levelizedbut still not a problem. On a level 40 yard (120 ft) shot with an arrow that travels 215 ft/s it would take 0.56 seconds to reach the target. In that length of time the arrow would drop about5 ft (x = 1/2 *32*t^2). Now that’s a pretty big drop. However, we do not see that since we arch the arrow to the target.My calcs show a little over 2 degrees is the required arch. Because of the arch, we must look atour arrowspeed using the same Pythagoreans theorem as above such that part of the speed is in the levelized direction and part is away from the ground.Gravity will overcome this and start pulling the arrow toward the ground such that when we reach the target we are at the levelized point. Now lets shoot at a downward angle (40 yds from 20 ft high or 9.6 degrees). The distance to the target has been reduced by 2 feet but gravity is now assisting the arrow in its movement towards the target. This combined effect with the slow bow results in an impact that is1.2 inches high. As arrow speed increases, this difference of course decreases.

Now for their example, 40 yards line of sight at 40 degrees. This places the hunter at an elevation of 77.2 feet (ouch) above the target with a levelized distance of 92 feet. Using our 40 yard pin with its 2 degree arch will result in an arrow that is 1.6 feet high. Using the levelized distance method we would use a pin set at 92 feet (~31 yds). This results in an arrow impact that is 1.6 inches high. Adjusting to a pin set at 34 yards (as suggested by Leupold) results in an arrow that is almost 6 inches high. However, if you add in some wind resistance to slow the arrow down, which I am sure they do, the 34 yard pin will probably come in real close.

Thus, I would have to say that their example is probably correct. However, I do not think that it is realistic. If you use a faster bow or hunt from a reasonable height, any range finder will get the job done.

Kelly/KY

Hey War...where were you before I dropped $ 300 on this thing!!!

LOL...gotta love engineers. Just couldn't let the hype pull you in..had to go and spoil it for me.

Kelly

nodog

Well this is a good topic. I wonder what the company would say?