Thanks a hundred times. Wondered about the correction factors too. So - on a scope with 1/4 MOA adjustments I'd input, what?
Care to go into some atmospheric inputs on the Shooter app? Absolute? ASM? ICAO? Enable Zero Atmosphere? MV Variation?
The correction factor really just refers to the percent error of your turret's actual adjustments compared to advertised. So if you select 1/4 MOA adjustments in Shooter or Ballistic:AE or any other good app, and your turrets truly adjust 0.25 MOA, then you'd leave the correction factor as "1". If it adjusts 0.23 MOA, then you'd enter 0.92 in for the correction factor. If one click adjusts 0.27 MOA, you'd enter 1.08, and so on. EDIT: This is how Ballistic:AE works, which is what I use, but it looks like the Shooter app does the inverse of this. So with Shooter, if your turret actually adjusts 0.23 MOA, you'd enter 1.087.
Absolute pressure refers to whether you're entering the actual air pressure compared to a vacuum, or if you're entering air pressure corrected for sea level. If you're located a few thousand feet above sea level, and you see a reading of 29.92 InHg, then you're reading relative, gauge, or barometric pressure. If you look at your Kestrel and see a reading of 25.62 InHg, then you're reading absolute pressure. Absolute pressure read off of a handheld device is preferred, as it bypasses conversions and local weather station input. FYI, if you have an iPhone 6 or newer, your phone has an air pressure gauge built in, and you just have to get the "Barometer" app to get absolute pressure readings from your phone without having to use a Kestrel or similar.
Enable Zero Atmosphere means that your app will compare your current shooting atmospheric conditions with the conditions present when you zero'd the scope with that load, and will calculate the difference in your zero for use in your current shot solution. If this is clicked off, the app just leaves your zero the same for any atmospheric condition.
I use Ballistic:AE instead of Shooter, so I'm not 100% sure, but I'm guessing that MV variation is a measure of the temp sensitivity of the powder you used in your load, and how much the MV changes for each degree F in temperature change.
ASM and ICAO are just two different atmospheric standards that bullet companies reference when advertising BC values. The Shooter app manual says this: "Berger, Nosler and Lapua all use ICAO. Sierra, Barnes, Hornady and Winchester use ASM". Not a big deal which you select, as it doesn't make a big difference.
The manual can be found here:
https://www.shooterapp.net/manual.phpNote: Read the manual for whatever app you use, as the terminology used between different apps can refer to different things.
