I have a few boxes of 38s and some 44s. I think they also made plastic bullets to fit 45 ACP too...wax does work...thinner than boughten gulf wax though
I spray my mold with pam then with the sprue plate open, force hot glue into the cavities. A rubber band around the handles helps keep the mold closed during the process.
It has been a while since I made any and hate to tell you I can't recall how long I had to wait for the glue to cool enough to solidify. Drop the bullets out and with a razor blade trim the base. I do remember that maybe 30-40% of the bullets did not come out well enough to uses.
I believe that there are several different types of glue sticks available. Perhaps some of them may work better than others for casting. I do not have a glue gun to test that possibility. Also, dunking the bullet molds with glue bullets inside into an ice water bath might speed up cooling.