Ya won't know if ya don't go.
I did a silly thing in 2003 right after getting the CZ-550 in 9.3 x 62 Mauser. Several silly things, in retrospect--but all of them turned out to work fairly well and at the same time.
There were two choices of brass in 2003 for 9.3 x 62........slim, and none. There WERE Mauser cases with the wider .480" head diameter (vs. the usual .473" of 308. 30-06, et al), but the easily-had cases were too short (55-57 mm long). RWS and Norma brass could be had, but with kids in school there was way too much month left at the end of the money to indulge in that sort of largesse.
Remington 35 Whelen brass, to the rescue. That's Part One of the saga. Part Two involves bullets that fit the throat and grooves of this oddball caliber. Not such an oddball in Europe, but here in the US of A .366" bullets are kind of a trivia question. I had already succumbed to the allure of the 9mm Makarov some 10 years previously, and Hornady made jacketed bullets of 90-95 grains to feed these little Com-Bloc blow-backs. So did Speer (.363"), Sierra (.364"), and Hornady @ .365". Close enough for government work. Fuel selected was some of the remaining WC-852/fast lot from the GI Brass milsurp powder fashion uptick, which I thought would work well enough to 1) launch the uber-light-for-caliber projectiles and 2) provide sufficient pressure to help blow the shoulder forward 1/10" from the 35 Whelen shoulder setting.
I ran 10 of the 35 Whelen brass through the tapered expander ball of the 9.3 x 62 sizing die, gave it an unrecalled weight of WC-852 (about 95% density) and brought rifle and loads along for one of the Bomb Squad Weekends where those maniacs destroy seized explosives way out in the desert. That event had the added entertainment venue of "Let's Help Al Blow Up His Brand-New Rifle" to the weekend's festivities. The first few were fired remotely, and worked without incident. Bullets went downrange, shoulders blew forward perfectly, and the Mauser claw extractor held the case properly. The remaining rounds were fired standing/offhand, and printed close to the iron sights at 50 yards. The guys were a little bent outta shape that I only brought 10 rounds, but they had enough of their own guns and ammo to keep dull times at a distance. We certainly did.
I spent the next few months running the remaining 90 9.3mm Whelen brass through the rifle as above. Let me say here, .365" 90 grain JHPs meant for 1100 FPS do VERY BAD THINGS to jackrabbits and ground squirrels they connect with at 2900-3000 FPS start velocities. The bullets held together fine in the 3 turns/meter rifling, shot with decent accuracy, and I still have all 100 of the original 35 Whelen cases on hand and in good condition. These get used for cast bullet loads in my CZ-550, usually running a 270 grain GC flatnose in the 1700 FPS ballpark (educated guess) atop 23.0 grains of 2400.