Properly Chambered Throats

[SCR]

This is a video of the throat at the end of a chamber on a 6 PRC Primal.

For concentric and symmetrical throats you must have multiple things. Good bearings in the lathe, proper indication of the barrel, rigid and stress free fixturing, and good barrel groove geometry.

A symmetrical throat is imperative to a good precision rifle. So long as the barrel makers do their job, all of them turn out this way at SCR.