ORIGINAL: mcawful
I don't know about the T/C , but my Trade rifle (1:48) likes Conicals more than PRB. I shoot a LEE REAL conical in 320 grain, with very good results. I tried some No Excuses 460 grain and all I did is bruise myself.
I believe the REALs, in .50 caliber at least, are short enough to work pretty well in a slow twist barrel (1/60" or slower).