Chair gun question.....

[Tygon]

When in the reticle screen, what’s the difference between the cal mag and mag tab in the top two corners?
My mil dots were slightly off so I was manipulating the ranges by varying the cal mag number?

[TwiceHorn]

Cal mag means "calibrated magnification," or the magnification at which the space between two dots is a milliradian.  Standard mil-dot specifications call for that to be 10x, but manufacturers vary, so check your manual or specs.

Mag is the actual magnification setting.  At different magnification settings, you will have a different "ratio."  That is, the actual span, theoretically, is milliradian x "cal mag"/actual mag.

I say theoretically because frequently the mildots don't actually span a complete milliradian (or more than a milliradian) at the "calibrated magnification."

You can empirically determine whether your mildots actually span milliradians at calibrated magnification and "math" all this stuff out, but it's probably simpler to shoot it at your preferred ranges and magnfications and observe the drops yourself.  Chairgun can get you pretty close, but a lot of us find that actual shooting is the only way to go.

[Ol'DeadEye]

CalMag can be adjusted per attached photos.
Never done it myself, as I'm just a short range plinker.
Might be worth a try.

[TwiceHorn]

Cal mag means "calibrated magnification," or the magnification at which the space between two dots is a milliradian.  Standard mil-dot specifications call for that to be 10x, but manufacturers vary, so check your manual or specs.

Mag is the actual magnification setting.  At different magnification settings, you will have a different "ratio."  That is, the actual span, theoretically, is milliradian x "cal mag"/actual mag.

I say theoretically because frequently the mildots don't actually span a complete milliradian (or more than a milliradian) at the "calibrated magnification."

You can empirically determine whether your mildots actually span milliradians at calibrated magnification and "math" all this stuff out, but it's probably simpler to shoot it at your preferred ranges and magnfications and observe the drops yourself.  Chairgun can get you pretty close, but a lot of us find that actual shooting is the only way to go.

In chairgun terms, it is applying the ratio above cal mag/actual mag or indicated magnification as it is apparently labeled in your version.

If you tinker with cal mag, other than to set it to your scope's calibrated magnification, you're just dinking with the mildot span.  This is a very crude way to "curve fit" using chairgun.  Better adjustments to try to get your chairgun data to match your real world data are sight/scope height and the ballisitic coefficient of your pellet because these adjust the whole curve, whereas dinking with the mildots applies a linear correction across the curve at all points.