a1smokepole
My 52cal is one of the few i didn't JB right away. It is a LRH 52cal and the sabot fit/"feel" is nearly perfect IMO and the bore was sweet right out of the box. IMO clean it well and shoot it first. Then decide if you feel it needs to be polished.
I would get some 52x458 sabots and for bullets: .458 325gr FTX, Speer .458 350gr HotCor and some cheaper .458 300gr HPs like the Remingtons or Sierras. When you want to get a bit more fancy: Barnes .458 300gr SOCOMs and some Lehigh .458 samples in 275 or the over sized .459 277s. The new Lehigh 300gr ML bullet should be awesome too but ive never tried them.
Knight even recommends the 325gr FTX and at nearly 2000fps its a "big boomer".

IMO to take full advantage of the slightly faster twist, the 300gr+ bullets are the way to go but the little .458 220gr will certainly do the job too on deer.
BTW the 325gr FTX is on sale at Cabelas for about $28/50 and is quickly becoming one of my favorite affordable bullets even though im not a FTX/SST fan.