Thread: When can you weight sort brass ?

Originally Posted by 7mmwsm

If you weigh before trimming sizing etc you are weighing an unknown dimension.
If you size and do all your trimming and uniforming processes, then weigh, you are weighing a uniform external dimension.
So any variation must surely come from brass thickness. Which may or may not alter the internal dimensions /capacity of a case.
My last process is weighing loaded rounds, really just as a safeguard to check I haven't missed powder or used a different weight projectile.
I load PMC brass in one rifle and Winchester in another, same caliber.
If one of the other batch get mixed in, it's easy to spot because there's about twenty grains difference in the case weight. And quite different pressure signs in one rifle than the other.

Wouldnt you be better off doing a volume weight of whats in the case after its been fired ( for those that do it). Either water, fine powder or something repeatable. If the cases rim is a micro farad thicker or the rims rebate a touch deeper theres where you weight is going plus the wall thickness as you say. And what do you weigh with, grains? what is the volumetric difference of a 2 grain variance?
Its what floats yur own boat I guess, but just not on my radar yet

Yes I would think capacity/volume would give a more useful measure.
Then people talk about short fat cases creating more efficient burn than long ones with the same capacity. Then sharp shoulders bounce the burn back in to the case so don't erode the throat as fast.
It actually makes my head hurt.

There is no doubt that the Obsessive–compulsive personality disorder (OCPD) gene runs strong in the shooting sports.