I had a beautiful little guild-made German rifle with all the touches. I read they were made for the Germans in Africa between the wars. The cartridge doesn't get a lot of respect and is certainly not recommended for dangerous game, but I had a blast reloading for it. I carried it a few times for deer but never got to use it.
I had good results with all the faster IMR powders, 46 gr 4064 gave me 2100 fps, 43 gr 3031 was good for 2070, both with the 250 gr Hornandy. I got a 240 gr gas check mold and loaded 45 gr 4064 for 2185 fps and 42 gr 3031 for 2120. I had some 245 gr Kynoch factories that gave around 2250, although one sounded wrong and only clocked at 1415. Hmm.
You can shoot pistol bullets but they wont be accurate. I was determined to try and I built a crimp die by drilling out a piece of wood to accept the front of the cartridge, then drilled a small hole coming in from the side, put a decapping pin in and tapped it with a hammer 3 or 4 times around the neck just below the base. I think my brass was 8 m/m, worked fine as I got it, but the previous owner might have worked it in some way. Congratulations on your new toy.