0.419" is what is stated in the Reference Sheet on Berger's web site for the 308 cal. 215 gr. Hybrid bullet for bearing surface length. I imagine that is where he got it from.
I got it from the Berger spec sheet that is in the bullet data file on my laptop. I got that spec sheet from the Berger website. The same information can be found at the second sticky at the top of this forum.