No special moulds needed. There are some that people have come up with to make boolits specifically for PP, but it isn't necessary (and I have no knowledge of them myself). What I do is buy suitable boolits from a commercial caster, then size them, patch them, lube them and load them. For my M48, which has a groove dia. just a bit on the small side (about 0.3228"), I buy a 170 grain round nose/ flat point boolit, which was designed for the 32/40 or the 32 Winchester Special. I get them at 0.322" or 0.324" diameter. When paper-patching, you have to allow for the thickness of the paper (2 wraps)....which works out, in my case, to 0.010". So, first, I size my boolits down to 0.314"....then patch them. The finished product comes out at about 0.3245". As a final step, after lubing, I run them through a boolit sizing die that is just a bit smaller than 0.324". The final patched boolits are just about 0.324". They shoot wonderfully in my M48.
If you want to learn all about paper-patching.....fortunately, you've come to the right place. There is lots of good information here (check the smokeless paper-patching forum).....and many knowledgeable people also. I don't necessarily count myself as one of those, as I have only PP'd for the 8mm Mauser, but I can offer some minor help, here and there.