The 52 will feed flawlessly empty .38 hulls so I seat my wc cast bullets(sized .358 alox lubed)flush.The cases are WW brass with the 2 crimp canelures,the lower one done so as to remove some of the taper inside the the brass,making it straighter where the bullet fits in.
If you shoot at 25yds,any good quality cast 148 to 152 cast WC bullet will do the job.If you shoot at 50,the HBWC will better it but only if you qualify as an expert or master shooter.I've got a press to swage my HBWC and must tell you that I don't bother to swage my own as I don't shoot in comp anymore.
Old standbys will work fine in the 52.2.7 to 2.9 Bullseye,same with 700X,2.3 to 2.5 Nitro 100,3.2 of 231 and/or HP 38,3.0 Red Dot or 3.2 Green Dot...Experiment with your gun but I bet you'll soon be bored with the experiments since the machine is so accurate!