Leupold CDS info

[Trapper330]

Newbie here, just got a Leupold VX5 with the CDS dial and I'm wondering how accurate the altitude part needs to be when I send it in? I'm in WI at 1200 ft and hunt eastern Montana and Wyoming where the altitude is 4500-4700. I've heard there's a 1500ish ft sweet spot where you can be 1500 ft above or below? So I'm asking if anyone knows about that? or where should I list my altitude? 3000 ft?? Or ??? Thanks for any help you can provide.

 

[Smokeslider]

So using my shooter app, and a 300WM, 200gr ELD.

Difference in drop at your elevation at 500 yards is 1.4 inches
300 yards is a difference of drop 0.2 inches.

I'll let you decide if that difference matters to you

 

[gr8fuldoug]

I sent your question to our tech rep at Leupold and he replied "I always suggest to get as close to the elevation you will be shooting the most at. They will more than likely be shooting at that location as well for a zero-in there. When putting in your elevation for cds dial use the average elevation (dial is accurate +/- 2000ft)."

 

[Trapper330]

I sent your question to our tech rep at Leupold and he replied "I always suggest to get as close to the elevation you will be shooting the most at. They will more than likely be shooting at that location as well for a zero-in there. When putting in your elevation for cds dial use the average elevation (dial is accurate +/- 2000ft)."

In my situation would you go with 2000-2500 ft and figure its good for both? Do you think 3000 would be too much? am I splitting hairs!?

 

[gr8fuldoug]

2,500 but yes, probably splitting hairs

 

[Gingerman]

I have 3 CDS dials. Most importantly make sure your B.C value is true. I trust the real B.C.s from the Bryan Litz book. Or tell me what bullet you are shooting and MV and I can look it up. Zero when you get to hunt location. To answer your question, I'd put 3K and be a hair high at home. Depending how much you shoot at home, or hunt at home elevation, you could get another turret for 4K, but I just don't think the difference is justified for $80.

 

[SuperDUECE22]

also do not take for granted the velocities on the box if you are using factory loads. Max sure to chronograph loads to get a good average.

 

[Trapper330]

I have 3 CDS dials. Most importantly make sure your B.C value is true. I trust the real B.C.s from the Bryan Litz book. Or tell me what bullet you are shooting and MV and I can look it up. Zero when you get to hunt location. To answer your question, I'd put 3K and be a hair high at home. Depending how much you shoot at home, or hunt at home elevation, you could get another turret for 4K, but I just don't think the difference is justified for $80.

I'll be using Hornady American whitetail in 7mm-08 139 gr. The box says B.C. is .392 (G1) I agree that i think I can swing both elevations with the one dial, just wasn't sure about it?? or if it was a big deal?

 

[journeyman713]

I set my CDS up for the mountain altitude out west where I hunt, temperature too.
Rather be as spot on out there as possible!
Chances of shooting that long of distance in Wisconsin are not really a concern.
But I know it will drop a bit more here, so at the range, I add;
1 click at 400yds
2 clicks at 600yds

The mountain CDS is good for anything under 400, anywhere I hunt.

 

[ResearchinStuff]

go use the ballistics calculator on jbm to see how altitude, temp, and pressure affect your ballistics. Then you can decide if a CDS dial is accurate enough for your purposes, and what an appropriate set of inputs is for where you're shooting.

and you should absolutely not be using the numbers off the box for your dial, they're a crude approximation at best. get some real life dope if you don't have access to a chronograph.

JBM - Calculations

www.jbmballistics.com

 

[Trapper330]

go use the ballistics calculator on jbm to see how altitude, temp, and pressure affect your ballistics. Then you can decide if a CDS dial is accurate enough for your purposes, and what an appropriate set of inputs is for where you're shooting.

and you should absolutely not be using the numbers off the box for your dial, they're a crude approximation at best. get some real life dope if you don't have access to a chronograph.

JBM - Calculations

www.jbmballistics.com

Thanks!