How helpful is slope compensation in a rangefinder (hunting mountains)

[sscoyote]

I use the old Sniper tools ACI as well myself when i'm hunting the mountains here--simple enuf to use.

 

[Mr. T]

Range Finders

I bought the Bushnell Scout 1000 ARC and it works well out to a little over 600 yards. On reflective objects it is supposed to go out to 1000 yards, but for practical purposes it will only go out to 600+ yards for game. The furthest range it's recorded is 622 yards and it gives you the angle and related compensation in the site window. It has a bow mode and a rifle mode. It was on sale last summer for $345 at Gander Mountain. I'm not sure where the prices are now for them.

 

[JWF III]

Art Hit the nail on the head with his answer. IE-it really isn't neededin most practical hunting situations. If it is needed, you need a lot of practice at the shots,then those rangefinders might be worth the money.

Basically, the closer to vertical you are shooting, the less gravity affects the trajectory of the bullet. An extreme example would be shooting strait down at a target 300 yards directly below you. A 300 yard horizontal shot would require around a foot of holdover, but if you are shooting down gravity will pull the bullet strait forward along the path you aimed it rather than deflecting it away, so there is no holdover required and you can aim directly at what you’re shooting at.

Basically correct, but if you're shooting at 90 deg. downhill, the line of sight is not the trajectory of the bullet. If you aim dead on, you'll miss by as much as a couple of feet at 300yards. This could possibly be the hardest shot possible to make. We're just lucky that it doesn't come around very often (if ever in our own hunting life).

Correction to previous paragraph- If your vertical wire of your scope is along the length of an animal, you may hit it holding dead on, just not where you're aiming. If your horizontal wire is along the length of the animal, holding dead on you'll definently miss it.

Wyman

 

[Dr. Tad Hussein Winslow]

And interestingly, it doesn't matter whether you're shooting uphill or downhill. The point of impact is always HIGHER with an uphill/dowhill shot, than the lasered distance would make you think you should hit, compared to a horizontal shot of the same lasered distance. So you have to estimate holdUNDER instead of holdover with an uphill/downhill shot. Actually you have to estimated holdunder, the take the difference between the holdunder and the appropriate holdover for the straight lasered range. Might be a net holdunder, or might be a net holdover, depending upon circumstances.

Some people think you aim lower on a downhill shot, but higher on an uphill shot, but that is not the case. Always aim lower than otherwise.

This can become very important with shots over 20 yards with a bow/arrow, from a treestand, particularly if you're way up there, 15 feet or higher.

 

[sam700]

Thanks for the help. I ended up going with the Bushnell 800 since it seems like it's unlikely I'll have shots that are both long and steep. Also I figured that with the 800 it should range animals pretty easy at 400 and the other model might have a bit of trouble with it. The fact that they had a great deal on the 800 at Sportsmans warehouse helps too.

I did a bit of testing yesterday and found that it works pretty reliably dirt hillsides to 600, trees to 650 and reflective objects like white buildings have worked to just a bit over 900!

 

[MCgunner]

I have a 400 yard bushnell rangefinder. It'll range that far on a deer if there's a nice white rock near him. Otherwise, it has problems beyond 300 on some dark objects. I got it when they first came out. I may get a better one if I go back west, but 400 yards is my absolute shooting limit, so I really don't think I need much more rangefinder.

 

[~z]

Doc, it is all the same, gravity acts on the horizontal length of the bullets path regardless of the angle. That is the easy part, now what the wind is doing across there...
~z