I think the .32 acp is technically called semi-rimmed. I am looking at one right now, the rim does extend beyond the case sides, so it may chamber and headspace on your older S&W, but not by much. I also have one of these older Smiths, and it is one of my favorites. If indeed the pressures are too high on 32 acp, I would be leery of accidentally putting the wrong loaded (full power) 32 acp loads in it. I would suggest just getting a set of cheap Lee dies for your 32 long. Thats what I load with. I think they run in he 20-odd dollar range, and come with a shellholder. Thats probably the safest thing to do. As an aside, the extra bullet jump from shooting the acp's in the S&W probably won't help accuracy, and those little hand ejectors can be amazingly accurate. Mine will shoot well under 1-1/2" at 25 yds. with handloads. If your Smith is a fixed sight gun, the sights are probably regulated for around 100 grain bullets anyways, probably heavier than the 71 grainers you normally load in the auto's, meaning it would probably shoot pretty low. Hope this helps.