The ban on lead bullets, particularly heavy ones has to do with bullet pull. If you've got one or more of the guns, go test it. Its easy, and in my experience you won't destroy the gun on the first shot or two.....
Just take a pad of paper, a pen, and a measuring device. I use a micrometer, but a dial caliper will also work just fine. A permanent magic marker will help. Just number the cases from 1 to whatever, or letter them A to Z, etc. Then measure each and write them down. That part isn't difficult because commercially produced ammo is pretty darn consistent. Then load up the gun and fire a round. Open the cylinder and measure them again.
What I found even with +P 38s in my 337 was that after the first shot, all were moving. Even at a consistent rate, the OAL was increasing. After a 2nd shot, the remaining 3 were longer still. I stopped after the 3rd shot because they were far enough out I'd proved my answer.
I don't really understand the bullet weight issue because longer bullets should have a longer bearing surface for the case to hold. It also seems to argue against reloads using questionable cases. I would think once fired brass would still be OK, but if you comingle your cases, where one may be once fired and the next 20 or more cycles, you may have a problem.
Even the reloading dies may create a problem for you. If your sizing die or expander is a little out of spec, be it a manufacturing defect or wear, you may get cases that can't hold the bullet.
With the SC guns, or even with the Ti guns, like my 337 or 396 guns, the answer is you should be careful. Just take the ammo you plan on using and do your own tests. If you're using your own reloads, do the simple tests outlined above. It won't kill you, and you'll learn somthing about your gun and ammo.
What I've done is pretty simple. I restrict my target loads to 148 Wadcutters in .38 calibers. My carry ammo is factory jacketed within the recommended weight range.
With 44s, it was easy. At a gunshow last year (the events were reported by Charlie Sherrill) I located a guy selling down 44 Special self defense ammo cheap. I had to interrupt my Bull session with Charlie a couple of times to run off and buy the stuff. He's a known hoarder (he's infamous for it), he was a little shocked that I kept coming back with armloads of ammo. And he's never even seen my "tiny" stock pile of handloaded stuff! The prices I was paying a year ago was almost a giveaway compared with prices today.
We all enjoy stretching the rules a little. When you decide you want to do that with your firearms, you'd best test your grand theories before you cause yourself a problem.