Twist rate for 180 bergers in a 280 AI ?

[tammons]

I know Berger recommends 9 twist but I have seen online people commenting that 168 bergers at distance were keyholing with a 9 twist so was thinking I probably need an 8 twist for the 180 bergers ?

[Robinhood]

If their M.V. was not fast enough I could see that at extreme long range.