CDS systems at different elevations.

Raghornklr

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Jan 29, 2019
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Out west
I guess I’m just curious, a lot of my hunting occurs at different elevations in the same year and I’m getting pretty attached to using one gun for all of it. Plan on adding a VX5hd 3-15 to the system.

If I’m elk hunting in the 5-8k range in one state and then at sea level a week later how much will that effect point of impact with a cds system? Are the effects mitigated at shorter ranges say sub 550 or would it be wise to have a separate dial made for the same load but adjusted for elevation?

Thanks for any light you can shed on this.
 

Jskaanland

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Kennewick, Wa
I'm currently regurgitating the answer from @Broz I got the other day. He said you will start seeing POI errors, when not taking atmospherics into equation, at the 500-600 yard range. I've tagged him to allow him to elaborate.
 

OutdoorAg

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Feb 17, 2013
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This is where having a moa reticle and moa clicks OR mil reticle and mil clicks will trump any “custom turret” built to a specific load. You can hunt any elevation on earth and you aren’t stuck with a dial that’s off.
 

mt100gr.

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This is where having a moa reticle and moa clicks OR mil reticle and mil clicks will trump any “custom turret” built to a specific load. You can hunt any elevation on earth and you aren’t stuck with a dial that’s off.
This! Learn to shoot with MOA or MIL corrections. Elevation and atmospheric pressure (or density altitude) AND temperature all affect your trajectory. 8000' and 20degrees vs sea level at 50degrees and all points in between have variable environmental factors acting upon a bullet in flight.
 

prm

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Mar 31, 2017
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VA
When I had a CDS, I set it up for 4,000’ elevation. Then I could hunt sea level and the 9-10k for elk and mulies and be within one click. One more clock at sea level and one less at high elevations for long shots.
Edit: I never planned to shoot beyond 500 so it worked within my limitations. Would not recommend that method for longer planned shots.
 

Travis2282

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Sep 20, 2018
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I have read recent review on newer phones the app doesn’t work well but download Swarovski ballistic app you can change sea level and use different factory ammo or custom loads and check and see the difference between clicks. I use this to set up my z5 scope. Works great to me!
 

timberbuck

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Mar 31, 2018
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Utah
Leave the standard MOA turret on the Scope. Get on a your ballistic program and print out drop sheets in MOA for the elevation and conditions your will be hunting, carry while hunting.
 

hoss1280

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Jan 12, 2018
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Location
Arizona
I guess I’m just curious, a lot of my hunting occurs at different elevations in the same year and I’m getting pretty attached to using one gun for all of it. Plan on adding a VX5hd 3-15 to the system.

If I’m elk hunting in the 5-8k range in one state and then at sea level a week later how much will that effect point of impact with a cds system? Are the effects mitigated at shorter ranges say sub 550 or would it be wise to have a separate dial made for the same load but adjusted for elevation?

Thanks for any light you can shed on this.

Thanks for the post I've had the same question. Haven't pulled the trigger on as CDS scope yet.
 
OP
R

Raghornklr

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Jan 29, 2019
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79
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Out west
No problem, finding out it’s more complicated then I’d anticipated.

Option B , stick with what I’ve been doing and zero at 300. Hold on to 300 and 10” higher at 400. I may just keep it simple.
 

30338

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Jun 2, 2013
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587
Spring is the time to play with this stuff. For $50 you can see how easy dialing elevation is. $270 SWFA 6x on April 15, use it and keep it. Or use it and sell for $220. Cost of a pizza and a couple of beers. You can use JBM Ballistics for free or buy Ballistic AE for your phone. If you can use scissors and tape, you can have a custom drop chart for any conditions. Simply range, dial, make your wind call and shoot.


We've killed enough stuff from 500-700 yards the last 8 years to make it all very worthwhile. Even if you don't plan on going past 500 yards, it will still improve your field accuracy using a scope that dials precisely. Tough for folks to get their heads around a $270 scope performing as well as these, but there it is.
 

2five7

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Jul 15, 2017
Messages
223
Here is a basic comparison for you.

Using a 6.5 140 Berger launched at 3075 MV, with a 200 yard zero. I'm using DA for atmospheric.

At sea level you need 6.3 MOA (33") elevation at 500 yards, and 2.4 MOA (12.6" wind). (10 mph 90 degrees)
At 8000' DA, you need 5.9 MOA (30.7") elevation, and 1.8 (9.6") for wind.

So at the extremes, it can definitely be an issue. Slower cartridges, or bullets with less BC would be affected even more.

I have a custom turret made for for my home stomping grounds, and I keep the factory MOA turret just in case I need it for an out of town hunt.
 
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