I have a older 25-2 which has larger throats and is picky about the loads it likes. I figured it out now with 0.454 dardas 200 gr and that was a long search. It does not even like AC but only auto rim.

Yours I hear is absolutely excellent, they made correct 451 or 452 throats and it will be great with standard factory ammo is what I have been reading. I would eventually need one too. Or a 25-7 which is good too apparently. Enjoy, it should be a blast to shoot some winchester ball through this. Moon clips prepared at home are cool too. No need to fiddle with loading, just drop in.

Last thing, since the round rests on the case, not on the rim, any slight debris building up or even the smallest little spec of unburnt powder will leave too little space and make the cylinder jam at least on mine. I always brings brush for the extractor star (clean underneath) and a brush for the throats since I do to want any jamming messing up the ratchets but undue force turning the cylinder. At least what I food shooting mine. Enjoy!