It's just a proportion. In simple terms:
1st dot : 1.4 MOA * 16 power / current magnification = current MOA
So
@ 4 power:
1st mark: 1.4 MOA * 16 power / 4 power = 5.6 MOA
2nd mark: 4.3 MOA * 16 power / 4 power = 17.2 MOA
etc.
@ 9 power:
1st mark: 1.4 MOA * 16 power / 9 power = 2.48 MOA
2nd mark: 4.3 MOA * 16 power / 9 power = 7.64 MOA
etc.
Simplified, it's just
Current MOA = original MOA * 16 / current magnification
1st mark: 22.4 / current magnification = current MOA of 1st mark below center
2nd mark: 68.8 / current magnification = current MOA of 2nd mark below center
3rd mark: 115.2 / current magnification = current MOA of 3rd mark below center
4th mark: 166.4 / current magnification = current MOA of 4th mark below center
5th mark: 240 / current magnification = current MOA of 5th mark below center
Hope this helps. Let me know if I'm way off.
1st dot : 1.4 MOA * 16 power / current magnification = current MOA
So
@ 4 power:
1st mark: 1.4 MOA * 16 power / 4 power = 5.6 MOA
2nd mark: 4.3 MOA * 16 power / 4 power = 17.2 MOA
etc.
@ 9 power:
1st mark: 1.4 MOA * 16 power / 9 power = 2.48 MOA
2nd mark: 4.3 MOA * 16 power / 9 power = 7.64 MOA
etc.
Simplified, it's just
Current MOA = original MOA * 16 / current magnification
1st mark: 22.4 / current magnification = current MOA of 1st mark below center
2nd mark: 68.8 / current magnification = current MOA of 2nd mark below center
3rd mark: 115.2 / current magnification = current MOA of 3rd mark below center
4th mark: 166.4 / current magnification = current MOA of 4th mark below center
5th mark: 240 / current magnification = current MOA of 5th mark below center
Hope this helps. Let me know if I'm way off.