I'm shooting an 8 twist Criterion 223 Rem, and 73 Bergers. They're doing slightly better than the 69 Lapua's I've been using, but your post has got me thinking I'll try the 73's in my stock Savage 223 with a 9 twist varmint barrel. I'll try to get back with the results.
Here's a link to a stability calculator;https://bergerbullets.com/twist-rate-calculator/
Here's a link to a stability calculator;https://bergerbullets.com/twist-rate-calculator/