scope correction factor

[Randy dawson]

If you have a scope correction factor of say 4% how do you adjust a ballistic calculator to take this in account? I have an idea but was wondering how other people did it. Do you change the bc or velocity to match the 4%? I don't know what mine is exactly yet but I know its some. Please don't tell me I need a new scope. I just need to figure the right formula for the one I have. thanks

 

[coyotemaster]

4% is quite a bit imo. I'd think you could fudge the B.C. Number a bit and be close. Bryan Litz addresses this error in his video explaining the tall target test.

 

[Randy dawson]

I watched the video. But this is why I have the question. He tells you how to figure it and what it is. But not how to correct it

 

[coyotemaster]

Ok I would shoot at 300 400 500 if you have the space and juggle B.C. and/or velocity to stay close to adjusted elevation.Is this scope repeatable?

 

[Blancoalex]

Think your talking about turret click value. Your scope is adjusting either only 96% or 104% per click. You should have place in your app to make this adjustment.

96%(.96 moa/mil) acutal movement would need you adjust your app to correct to 104%
104%(1.04moa/mil) acutal movement would need you adjust your app to correct to 96%

My Shooter app correction is adjusted in the firearm setup under Elevation Correction Factor or Wind Correction Factor.

This only appiles if you have 100% proven your scope has this error.

It is good you discovered this as the error adds up the further out you go.

Hope this helps.

 

[jebel]

Think your talking about turret click value. Your scope is adjusting either only 96% or 104% per click. You should have place in your app to make this adjustment.

96%(.96 moa/mil) acutal movement would need you adjust your app to correct to 104%
104%(1.04moa/mil) acutal movement would need you adjust your app to correct to 96%

My Shooter app correction is adjusted in the firearm setup under Elevation Correction Factor or Wind Correction Factor.

This. I use both Applied Ballistics Mobile (ABMobile) and Ballistic AE. They both also allow you to correct for the true turret click value.

 

[coyotemaster]

That's good info. Never delved into settings on programs.old dog/ new trick!

 

[Canadian Bushman]

4% sounds like a lot.

If you are determining correction factor with live fire chances are it will not be correct.

This needs to be done with the scope mounted firmly, optically centered, and aimed at properly scaled ruler or grid standing plumb and square at a very precise distance. I usually do it as close as i can and have the scope be parallax free.

Out of the handful of scopes ive tested for tracking errors, most resulted in a correction factor that was essentially lost in the size of my groups. Most were something like .997 or .998 for correction values.

 

[Canadian Bushman]

Shooter App

AB App

 

[badthirtyone]

4% sounds like a lot.

If you are determining correction factor with live fire chances are it will not be correct.

This needs to be done with the scope mounted firmly, optically centered, and aimed a properly scaled ruler or grid standing plumb and square at a very precise distance. I usually do it as close as i can and have the scope can be parallax free.

Out of the handful of scopes ive tested for tracking errors, most resulted in a correction factor that was essentially lost in the size of my groups. Most were something like .997 or .998 for correction values.

Great response.