Leupold CDS dial - chrono neccessary?

cletuz

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Mar 22, 2021
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2
Location
Alberta
Hi all,

I've recently purchased a Leupold VX-3i 4.5-14x50 CDS-ZL Duplex reticle scope for my Sako A7 roughtech pro in 7mm rem mag with 24.4" barrel. I was curious how critical (if at all) it would be to chronograph the gun in order to get the most out of the custom dial. I am shooting Federal Premium 160gr factory loads with the PSP Nosler Partition bullets. I'm just reluctant to purchase a chrono only to use it for one range trip and have it sit on the shelf if it isn't necessary. Thanks in advance for your advice!
 

KineKilla

Senior Member
Joined
Apr 8, 2020
Messages
380
Location
Utah
It is critical. When I first had my dial cut I found someone local that would allow me to borrow (we just met at the range) their chrono.

Leupold uses only a few factors when cutting the dials so you wouldn't want to be missing one. It is worth the small hassle.
 
OP
cletuz

cletuz

Newbie
Joined
Mar 22, 2021
Messages
2
Location
Alberta
It is critical. When I first had my dial cut I found someone local that would allow me to borrow (we just met at the range) their chrono.

Leupold uses only a few factors when cutting the dials so you wouldn't want to be missing one. It is worth the small hassle.
Appreciate the feedback, thank you.
 

BRTreedogs

Senior Member
Joined
Nov 16, 2017
Messages
3,168
Location
Central Oregon
It cannot be understated how absolutely critical it is.
Otherwise your just shooting in the dark. Mise well make a guess and just crank your turret.
Whatever is printed on your box is just one sample of one barrel in a controlled environment.

Download the free hornady ballistic app.

Put in all the info you can gather to as the shooting conditions you expect.

Set if to the farthest yardage you expect to shoot.

Then go back in and adjust the velocity around say 20 fps and see how much difference it make.

Cds is a pretty poor way to go unless you really only hunt im one spot for one season. Conditions change so much.

Do some more research on just leaving the moa turret in place and using a ballistic solver app.
That way you can get a correct dial up for every shot.
If you really need a yardage mark just use the app and make one using a piece of tape for that specific hunt.
 

Kenn

Senior Member
Joined
Nov 3, 2019
Messages
121
Location
Oregon
I don't have a chrono so I shot some rounds at 400 & 500 yards then used the drop to backward determine the velocity. Not ideal I suppose, but it worked fine for me. I agree with others that the CDS is not that important. Ultimately I just use the standard MOA dial with a DNA rangefinder.
 
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ThinkLeicaBuck

Senior Member
Joined
Sep 18, 2019
Messages
261
Hi all,

I've recently purchased a Leupold VX-3i 4.5-14x50 CDS-ZL Duplex reticle scope for my Sako A7 roughtech pro in 7mm rem mag with 24.4" barrel. I was curious how critical (if at all) it would be to chronograph the gun in order to get the most out of the custom dial. I am shooting Federal Premium 160gr factory loads with the PSP Nosler Partition bullets. I'm just reluctant to purchase a chrono only to use it for one range trip and have it sit on the shelf if it isn't necessary. Thanks in advance for your advice!
You gotta just bite the bullet and get one. The data is critical.
 

KineKilla

Senior Member
Joined
Apr 8, 2020
Messages
380
Location
Utah
I'm no expert but...

I've used my CDS dial in a variety of terrains and elevations. Different temps as well. It's a system that works and that is simple to understand and operate.

If you hunt from sea level to 10k feet then maybe not but for me living at or near 5k and hunting in elevations from 3k to 10k It's fine. I had mine cut for around 8,500ft and temps in the 40's....split the difference.

I'm not a competition shooter but it works for hunting or punching steel.

Use a temp stable powder and you can minimize that variance as well.

Sent from my SM-N976U using Tapatalk
37f5909aad8177d6a800aff4beb46659.jpg
 
Last edited:

ThinkLeicaBuck

Senior Member
Joined
Sep 18, 2019
Messages
261
I'm no expert but...

I've used my CDS dial in a variety of terrains and elevations. Different temps as well. It's a system that works and that is simple to understand and operate.

If you hunt from sea level to 10k feet then maybe not but for me living at or near 5k and hunting in elevations from 3k to 10k It's fine. I had mine cut for around 8,500ft and temps in the 40's....split the difference.

I'm not a competition shooter but it works for hunting or punching steel.

Use a temp stable powder and you can minimize that variance as well.

Sent from my SM-N976U using Tapatalk
37f5909aad8177d6a800aff4beb46659.jpg
Well put. I second what he has said here.
 

Decker9

Senior Member
Joined
Apr 10, 2015
Messages
368
Location
BC goat mountains
I don't have a chrono so I shot some rounds at 400 & 500 yards then used the drop to backward determine the velocity. Not ideal I suppose, but it worked fine for me. I agree with others that the CDS is not that important. Ultimately I just use the standard MOA dial with a CDS rangefinder.

This is what I did, and has worked well for me to my 500 yard max range. I recorded my drops out to 500, then played with the muzzle velocity on the app until all my drops matched the app readout’s drops. I also found out my bullet is traveling a lot slower (150 FPS slower) then I first thought as well, was quite a surprise.
 

JDZ

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Joined
Jun 12, 2014
Messages
493
Location
Texas
I don't have a chrono so I shot some rounds at 400 & 500 yards then used the drop to backward determine the velocity. Not ideal I suppose, but it worked fine for me. I agree with others that the CDS is not that important. Ultimately I just use the standard MOA dial with a DNA rangefinder.
This is what I did, and has worked well for me to my 500 yard max range. I recorded my drops out to 500, then played with the muzzle velocity on the app until all my drops matched the app readout’s drops. I also found out my bullet is traveling a lot slower (150 FPS slower) then I first thought as well, was quite a surprise.
This is actually more accurate than a chrono, so I'll go against the grain and say you do not need a chronograph. If you've got a place to shoot out to 500 yards, and can record the shooting conditions, you can calculate the speed. I'd rather do it that way than trust a chrono that could be off 20 fps. You'll want to correct the data anyway, assuming the sight in range is not where you're doing your hunting.
 

CMF

Senior Member
Joined
May 8, 2019
Messages
147
Location
Mississippi
What if I'm putting a CDS on a muzzleloader and using to 300yds. Are the temps and elevation going to make that big of a difference for the dial?
I'm literally at sea level on the gulf coast shooting in temps 80-95 and we'll be heading to NM for a muzzy hunt in October at 6-8k ft. temps I suppose 30-60.
I don't really plan on shooting that far on this hunt since it's a youth hunt, but the wife will use it too if she ever draws so I'm planning this to be a long-term gun and want to set it up right.
I also don't foresee us using this gun at home since our primitive weapon season allows single-shot 45-70 and we rarely get shots at deer over 150 here in MS.
I'm guessing from the comments so far, I should leave the moa dial, but I like the idea of having the yardages and just range and dial.
 
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