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View Full Version : Angle Comp., Rangefinders



shadow
08-06-2010, 12:29 PM
I have a regular rangefinder that works very well but it doesn't have the angle compensation feature for bowhunters on it so I went out and bought one that did.
Using the new Archers Choice rangefinder I notice that there is only a slight difference in a shot from 20 -30 yards or so. As an example the new AC unit will tell me a shot is lets say 22 yards from bowhunting height to an object near the ground and my old one will say its 23 yards. So it is a 3 foot difference, but with todays bows I don't think its gonna make that much of a difference at that range. Ranging out to 40 yards or so it seems to be equal. What are your thoughts on using range finders while trying to compensate for the angle difference. I now think that its so slight, I may just hold a bit lower.

MoodusHunter
08-06-2010, 12:50 PM
Math is all you need to know. The only distance that matters is length that gravity will act on the arrow. If you are say 20 ft up in a tree and the target is 60 ft away line of sight (your shot is NOT 20 yrds) it is 18.85 yrds. so barely a difference. And it gets even closer the farther you get from the tree.

There could be an extreme for instance one of my tree stands is on a crest of a hill. I climb up 20 or so feet, one side is a 45 degree drop off the other flat. With my rangfinder on the steep side I might measure 20yrds but only need to shoot a 5yrd shot b/c of the angle (wouldn't take because of the angle but you get the picture).

So if you hunt flat areas and climb the standard 15-25 feet into a tree the closer the target the more you need to compensate when using a rangefinder.

Here is a chart of actual distance vs. range finder(no angle comp) for in a tree:
15' Up
5 yrds range finder = 4 yard target
10 yrds = 8.66 yrds
15 yrds = 14.1 yrds
20 yrds = 19.4 yrds
25 yrds = 24.5 yrds
30 yrds = 29.6 yrds
40 yrds = 39.7 yrds
50 yrds = 49.75 yrds

20' Up
10 yrds = 7.5 yrds
20 yrds = 18.9 yrds
30 yrds = 29.25 yrds
40 yrds = 39.4 yrds
50 yrds = 49.6 yrds

25' Up
10 yrds = 5.5 yrds
20 yrds = 18.1 yrds
30 yrds = 28.8 yrds
40 yrds = 39.1 yrds
50 yrds = 49.3 yrds

Make a label tape it to the bow somewhere you can read it easily.

Now the real neccesity for angle correction is when you are hunting on a steep hill side out west.

StoneCrusher
08-06-2010, 02:07 PM
I had a 362 yard uphill shot that dropped my Mule deer. It was up an extremely sharp hill (35-deg). This was with a 7mm win mag with hot loads and 140grain bullet. (real fast and flat shooting)
To compensate for this incline, i only had to aim using my 300yr ballistic reticle dot in my scope to make the kill. (362yrd * .84 = 304yrds)

If I had aimed using the ~362yrd dot, I would have been about 6" over his back.

http://gundigest.com/article/playingtheangles/
UP or DOWN RANGE
05 Degrees .99
10 .98
20 .94
30 .87
40 .77
50 .64
60 .50
70 .34
80 .17
90 .00

ctdeer
08-07-2010, 09:56 PM
Thanks for the good info in this post. I have been looking at rangefinders and was torn between the two. This will defenitly help me make my decision.

Quigly
08-08-2010, 09:31 AM
I went to Cabelas and took two of the Leupold range finders to the edge of the second floor. One with the angle comp and one with out. The height is probably 20 or so ft, just like a tree stand. You can range things all around the store and see for your self that it isn't necessary for archery(out to 40 yds) to spend the extra cash. If you have plans to go hunting in the mountains with a rifle and take long shots on steep terrain, then yes, get the angle comp one...

shadow
08-08-2010, 05:26 PM
If you have plans to go hunting in the mountains with a rifle and take long shots on steep terrain, then yes, get the angle comp one...


After spending the money on the AC unit... i should have tried it at Cabelas. I didn't think of taking to look out over the store, I now must agree.
Also beware, the Archers Choice unit only ranges to 99 yards where my other one ranges out to 1000 yards.

MoodusHunter, thanks so much for the compensation chart you listed here . I will make some copies and tape one on somewhere for a quick reference while i'm bowhunting.

CrazyCajun
10-13-2012, 05:33 AM
I had a 362 yard uphill shot that dropped my Mule deer. It was up an extremely sharp hill (35-deg). This was with a 7mm win mag with hot loads and 140grain bullet. (real fast and flat shooting)
To compensate for this incline, i only had to aim using my 300yr ballistic reticle dot in my scope to make the kill. (362yrd * .84 = 304yrds)

If I had aimed using the ~362yrd dot, I would have been about 6" over his back.

http://gundigest.com/article/playingtheangles/
UP or DOWN RANGE
05 Degrees .99
10 .98
20 .94
30 .87
40 .77
50 .64
60 .50
70 .34
80 .17
90 .00


what kinda scope you using? I need to get a new scope for my 30-06 and would like one similar to yours (I think). I want one that has the different reticle dots for different yardage while also compensating for the round once calibrated.
I'd prefer Nikon but if they don't make anything like this I'd go to another brand.

StoneCrusher
10-13-2012, 10:10 AM
I use a Nikon BDC on my Winchester 7mm win/mag. with 3300 ft. per/sec reloads using 140 Nosler Partitions.

Dive4Blood
10-13-2012, 02:27 PM
what kinda scope you using? I need to get a new scope for my 30-06 and would like one similar to yours (I think). I want one that has the different reticle dots for different yardage while also compensating for the round once calibrated.
I'd prefer Nikon but if they don't make anything like this I'd go to another brand.

I would highly recommend a Nikon BDC scope for someone who isn't well versed in doping bullet drop. Their glass is OK, but if you use their Spot on App you can get hold offs for almost any round at hunting distances. You will just have to dial down the magnification until it puts the strike of the round and holdpoints at the distances you want. It is really easy to use. I have one Nikon BDC scope on a 300 wsm and have thoroughly tested and hunted it. It's good 2 go.