In addition to all the variables mentioned, case taper and case design also factor into bolt thrust. I recall Ackely doing some testing with bolt thrust and case design and he was able to successfully fire a cartridge in an chamber without locking lugs.
I'm not familiar with that action but if it isn't a headspace issue, I'd look at the counter bore clearance. Maybe it's a bit too tight and not allowing the extractor to snap over the rim.
Short Answer: Yes
Depending on the actual FP hole diameter and the fit of the FP you could shoot it as is. But you will likely experience some combination below:
Primer cratering
Primer flow into FP hole
Pierced primers
Even magnum SR primers are thinner than LR primers, with the larger...
What cartridge is it chambered for?
Long Action or Short Action?
Basic hunting rifles do not require a canted base.
QD mounts are overrated. Picatinny Rail provides the most options. Near Mfg get's my money for M70/FN Picatinny bases.
Your "once" fired brass. What chamber were they fired from? Was the LC brass fired through a machine gun?
The quality of the brass will be entirely adequate for your needs. The question is whether the cases can be resized to properly fit the chamber of that rifle and primer pocket longevity...
Since this has turned into motorcycle diaries, I'll play.
Back in 84 a riding buddy of mine was doing some sweepers, that we had done dozens of times before. He was on a lefthand sweeper and there was a oncoming pickup truck. I don't know if he went in too tight or the truck drifted wide...
I would think the PRC has a bit more effective case capacity. The PRC case has a larger diameter from base to shoulder by a fair amount. The WM case is a bit longer but a short neck so the bullet has to be seated pretty deep. With both seated to the same COAL, the capacity difference would...
I have three built FN-SPR actions and they were my primary rifles for the last decade but after the last barrels burned out I've been swayed by the prefit barrel siren lately.
There are a few chassis' that have the Winchester SA inlet available. Otherwise the pickings are pretty slim for DBM bottom metal (leftover CDI, PTG or FN OEM).
Thanks for the memory jog. I was trying to remember what those little green bottles were called that got me through college. Drank that shit by the multiple cases on Friday and Saturday night before going to the bars. Explains why I couldn't remember it.