I haven't figured out a way to predict which cases will or will not have tension after loading, so I've got about 1k PPU brass sidelined. If you can figure out what to measure and predict which cases will be sloppy loose and which ones will stay tight, let me know!
If it's worth your time, use a single stage press. While expanding/flaring the case, note which ones have little to no drag/resistance. Scrap those cases. This is very obvious and easy to determine, paying just a little bit of attention. I can easily tell the difference between, say, 45ACP cases that are no good, intermediate cases (mostly R-P/S&B in 45ACP), and cases with good tension. I never sort my brass by headstamp or by number of firings, anymore. While expanding/flaring, they sort themselves out; and with higher accuracy. Each successive round of reloading, a few more cases might go from borderline to bad.
Just cuz most of the PPU are bad, and most of your other brass are good, doesn't make sorting them by headstamp the final word. Sort while flaring, you'll find all the bad ones, no matter the headstamp. And you'll get some good reloads out of the PPU brass that you might have missed out on. You will rarely need to do a press test, and even more rarely need to use a bullet puller. Maybe only once or twice while learning.
I picked up a bunch of weird headstamp 223's recently. A near complete circle around the entire casehead, broken only in one spot by a little symbol (not a star/Starline). It seems they have the same deal as your PPU brass. A heck a lot of 'em had no neck tension off the bat. To the scrap bin. Some of 'em passed QC the first go, albeit mostly as "borderline." Surely as rain, a few more get weeded out on each subsequent reloading session during the expanding phase. I'm down to one or two. It doesn't bother me to know they're in the lineup. If they're good, they're good. Doesn't matter to me the headstamp or for how many more firings they'll last. I catch the bad ones when they're actually bad, even if the headstamp were to be LC/Norma/Lapua, whatever. The label doesn't give a case a free pass.
I scrapped a bunch of once-fired, still-crimped LC, complete with annealing marks, in fact. They all happened to have a 72 year stamp. I had that brass stored away for over a year, thinking it was gold. But the expander ball doesn't lie. The ammo factory can swap different sizing dies to accomodate large batches of "deviant" brass. Most reloaders don't have the time or inclination to bother with that, esp since you'd then have to sort out your brass each time you sized it.
If you are an obsessive headstamp sorter, then you might look into getting a custom sizing die, undersized by a mic or three in the neck area for rifle brass. (Or an adjustable neck sizing die.) But I don't think that would be as valid an idea for pistol brass, cuz you'd overwork the brass near the web. I suppose you could size in two stages, using the smaller die to only size the first half inch of the case mouth.
