Bushnell Legend Ultra Hd 4.5-14 and Chairgun not jiving

[jking]

Thought I try a new scope so through a recommendation I bought a Bushnell Ultra Hd mil-dot and mounted it on my Regal. The glass is crystal clear, the reticle is pretty fine and the side focus and the zoom are really smooth. The only negative on the reticle is that the "dots" seem larger than my Hawkes.
Here's the problem though.. Using Chairgun with all the correct entries and a zero at 60 yds, the mil-dots for hold over and hold under are not correct. Normally a zero at 60 means the first mil dot is really close to 70 and the second mil at 80. In reality though with this scope the first mil-dot is 75 and 80yds is only 11/2 mil-dots. Not sure what to think so I just moved my target until the hold over mil-dots where precisely on target. Any ideas out there?
jk 

 

[broekzwans]

Did you use the right mildot calibration magnification (14x) in Chairgun? I have the same scope but haven't had any issues with it..

 

[Ghostmaker]

Mine works out pretty much bang on Jimmy. I'm using Strelok Pro though not Chairgun. Quadruple check the data you are putting into Chairgun. I had an issue once where I couldn't get the Ballistics App to jive and it turned out I somehow had the wrong BC input into it. I couldn't see it for the life of me and it took someone else looking at it to see the error.

 

[jking]

Thanks guys, I've looked over all the data several times, even checked the humidity and temp. I using the Hawke's Generic 10X mil-dot as my reticle type and 14X when I set it up in Chairgun. I'll triple check it again. So Axel, did you find this particular scope in Strelok. Someone else had checked for me but didn't find this exact scope.
JK

 

[KYAirgunner]

If you have a chronograph you could find your own BC. Make sure your using the GA drag function. also even a ten degrees difference in temperature change can make quite a bit of a velocity change so that's another thing you should probably test with a chronograph. A ten degrees difference for my gun I've noticed to be about 20 FPS difference. Also make sure that your scope height is correct that's another pretty important piece of info. Good luck hope you figure it out. Also as long as your scope is mildot and its on its true power it shouldn't matter what reticle your using as long as its mildot.

 

[broekzwans]

This scope can't be found in strelok but you can use the generic mildot crosshair and calibrate it at 14x magnification. This is what I've done in my strelok app.

a very important parameter that needs to be (almost) correct is the BC value. The BC value has one of the biggest influences on the calculations

 

[spinj]

While correct BC value is critical, the MOST IMPORTANT parameter is scope height, however. A few hundredths of a different inputted value in BC isn't really going to translate onto significant output POI values between the two. But if your scope height is off even by a quarter-inch, the differences (between ballistic information from incorrect and correct scope height) are huge and can result into misses at further distances.