I know it's not a long range scope so to say, but I am getting ready to send in my order for a CDS dial. I have a ten shot average velocity calculated. What's the best way to measure sight height? How close does the elevation and temp need to be? I'll be using a nosler accubond, is the BC listed by Nosler good enough? Any other tips are appreciated
CDS Tips
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Bullwhacker
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Sight height: using calipers, measure the distance from the bottom of the scope to the top of the bolt, Scope tube diameter and bolt body diameter.
Scope height = Bottom of scope to top of bolt + (scope diameter/2 + bolt diameter/2)
Scope height = Bottom of scope to top of bolt + (scope diameter/2 + bolt diameter/2)
Wedgy
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What's the best way to measure sight height?
open the bolt and pull it back until it is even with the scope eyepiece then measure from the center of the scope eyepiece to the center of the bolt
How close does the elevation and temp need to be?
depends on how far you are shooting, run it thru a calculator like Berger's with the different variables and see what the POI change is https://bergerbullets.com/ballistics-calculator/
I'll be using a nosler accubond, is the BC listed by Nosler good enough ?
BC can vary quite a bit from gun to gun do to the rifling engraving the bullet ogive, it is best to get your drops validated and then get the turret made, remember, any changes in the bullet or ammo you're shooting will render the turret useless, as will a rangefinder that doesn't compensate for angles. Have you considered just getting an MOA or Mil turret and just dialing for your drops ? That way it is good for any bullet/ammo combination.
open the bolt and pull it back until it is even with the scope eyepiece then measure from the center of the scope eyepiece to the center of the bolt
How close does the elevation and temp need to be?
depends on how far you are shooting, run it thru a calculator like Berger's with the different variables and see what the POI change is https://bergerbullets.com/ballistics-calculator/
I'll be using a nosler accubond, is the BC listed by Nosler good enough ?
BC can vary quite a bit from gun to gun do to the rifling engraving the bullet ogive, it is best to get your drops validated and then get the turret made, remember, any changes in the bullet or ammo you're shooting will render the turret useless, as will a rangefinder that doesn't compensate for angles. Have you considered just getting an MOA or Mil turret and just dialing for your drops ? That way it is good for any bullet/ammo combination.
I have the standard CDS turret in MOA that comes with the scope, just figured it would be interesting to see what or how well their cut turrets are for the gun. I normally only ever find a single load for a rifle and just stick to that. Not real big on always trying something different.
Ricky C
Well-Known Member
Hey, when I sent in for the one and only so far, I used my Ohler chrono for fps, I took an average of the temperatures I'd be using it in, an average of the elevation, (shaded that a bit high), used the BC straight from Barnes. I've shot two Caribou over 400 yds and shot it out to 600. It's been right on.
Take Care
Take Care
I have used the shooting chronograph for my velocites, I also have an average of the temps I shot those recorded velocities at as well. I'll have to determine the elevation, Leupolds video they posted said its good to within in 2000 feet.
Just have to get close on the scope height. Easiest is like stated above: Open your bolt even with the back of your ocular bell and use a ruler or calipers to measure from the center of the scope to the center of the bolt. Easy-peasy!
Since a CDS is fixed once the input is used, I split the difference on altitude. As long as you are within 2000' you will be within reason. So, if you hunt between 4K' and 8K', I used 6K'. Has worked for me. I have MRAD scopes for dialing outside those perameters. Keep in mind, for $80.00 Leupold can make additional CDS caps for you, so if you hunt near sea level sometimes and then 10,000' mountainous terrain other times you could have additional dials.
Since a CDS is fixed once the input is used, I split the difference on altitude. As long as you are within 2000' you will be within reason. So, if you hunt between 4K' and 8K', I used 6K'. Has worked for me. I have MRAD scopes for dialing outside those perameters. Keep in mind, for $80.00 Leupold can make additional CDS caps for you, so if you hunt near sea level sometimes and then 10,000' mountainous terrain other times you could have additional dials.
