[Dusty Road]

Obviously your so called ballistician hasn’t seen a 55 grain pill moving at 4000 fps go up in a cloud of gray dust trying to push it down a 1-7 twist. I’ve seen them shear the jackets off!

[IndispensableDestiny]

If you don't like the opinion of a staff ballistician from Sierra Bullets, then try Bryan Litz's book on applied ballistics, page 141.

The bullet failure you described is not a matter of stability. It's also not something to worry about in an AR-15 platform.