I've been loading wadcutters of all types for over 50+ years (including double-ended and hollow base; I actually had to look up "double ended" just to confirm the meaning as I thought it was). I've used any and all range-picked-up brass with, and without cannalures etc etc etc. Everything shoots perfectly well always; with no problems ever. Over the last 40 years or so, I did learn about taper crimping my wadcutter ammo so, I've been doing that. It has "proved" to result in no major difference other than making a cleaner-looking cartridge. I'm told by the "eperts" that taper crimping will result in more accuracy; however, I personally don't care so I haven't bothered to confirm that information.
I live by KISS (Keep It Simple Stupid); and am always striving for mediocrity.........
J.