It was probably Remington brass, I did my best to wear out a box of 20 at a out the time I would have been testing the XCB bullet in my LR-308.
I've played the thicker brass game to extremes and while it can fix some problems, it isn't the whole answer to the alignment problem (believe it or not). Someone asked if there was enough room for the bullet to yaw as much as the engraves indicated and the answer is no....but that begs the question of how then? Well, once it starts crooked a little bit, inertia keeps driving it that direction until finally the bullet begins to deflect true to the bore again, so the point of the nose can be considerably off the bore centerline with only a slight initial (static) misalignment.
This is why static trueness of cartridge and chamber (tolerance stacking and a chamber cut straight) and minimizing cartridge runout (static bullet alignment) are often so important to accuracy.
Except. There's always an except, isn't there? WHEN the bullet shape is just right for the system, the alloy is if the appropriate ductility, and the powder pressure curve is tuned to match, you can sail that bullet at the throat from fifty thousandths away, several thousandths off-center, and a couple degrees crooked and it will still group under one MOA. I've measured runout to prove two degrees and figured the off-center based on tolerances of some loads and seen the results consistently on target.
Ever since I finally figured out the dynamic fit secrets (not secrets really, but just starting to understand just what the fit/alloy/powder relationships mean to each other has taken me the better part of a decade) I've gotten a lot less picky about loaded neck clearance and for most of my loads (1.5 MOA is just fine to me for ammunition which must be universal to many different rifles) I don't even bother to turn the thick side off of the case necks unless I'm really fine-tuning a target load.