Understanding SG (Stability Gradient) - AB Quantum™

[@amlt1164]

I change the twist rate from a "good" one to a "bad" one with a CDM and it doesn’t change the elevation. So if I have a bad stability, the only way is by using a G7 and implementing the suggested G7 number ?

[@clausziegler5720]

You calculate the stability factor at sea level. I would find it interesting if I could change the height over sea level (or below, there are a few locations on earth at land below sea level ...) and see how the stability factor is changing. If your main hunting location are the Rocky Mountains it is maybe a useful information??

[@willis45acp]

Yeah, ditto this. I run 208 30 cal Berger Hybrid in a 300WSM and it's stable at the altitudes I shoot at which is never sea level. So the ability to change the altitude you are shooting at would be highly useful.

[@AppliedBallisticsLLC]

The SG is calculated based on the entered conditions and displayed in pop up below the range input on the HUD.

[@bpm990d]

So SG stands for Stability Gradient? Hmmmm, been wondering that for at least 15 years. I'm almost as excited as when I found out what C-SPAN meant.

[@BryanLitzBallistics]

@@bpm990d SG is gyroscopic stability factor. SD is dynamic stability, when it's not Standard Deviation 😉 We talk about a stability gradient at transonic, but that's not what SG stands for.

[@bpm990d]

@BryanLitzBallistics Ohhhh! I am dissapoint. So do do we know what SG stands for when talking about gyro stability?

[@Papawsaurus]

When you changed to .073 it didn’t appear to correct the issue. If you have a problem like this can you search by correct bc when looking at factory ammo. You don’t always have a decision in twist but you might have a decision in selecting shelf ammo.

[@AppliedBallisticsLLC]

The Stability Gradient is a guide to understanding what is happening. If you decide to use those changes is entirely up to you. The application is not going to force it on you.

[@Coldbore375-lp6gj]

Hey Doc good to know. Update on the reticules is awesome. Still some issues at least with my android version. BCs are all messed up, claiming a 210 Berger has .922 G7, 180 gr Sierra BTSP at .698 G7? Also wont save CDMs on some. You can select them but when I save them reverts back to G7. Its getting better, hope this helps

[@AppliedBallisticsLLC]

Please write down the profiles that are giving you trouble. Delete the profile and application. Reinstall the application and recreate your profile. This should resolve your issue, if not please use the support button located within the application. That way our support team can assist you.

[@Lucas12v]

1/16 twist seems pretty standard on 22lr. Hard to believe that companies have been using the wrong twist for all these decades. Maybe they have though.