I can only offer second hand general consensus I’ve found from researching loads for old shotguns. The concern isn’t shooting a “hot” load pressure wise, as long as the gun is in good mechanical condition.
What can happen is hard shot like steel or tungsten can score the forcing cone, or “bulge” the choke. The hard shot won’t compress, so it forces the choke to give. From what I’ve read it may or may not affect patterning if this happens. So, In short, there isn’t really a “kaboom” safety issue to worry about but you may damage the barrel of your gun, at least cosmetically.
If you feel sentimentally about the gun in any way, I definitely wouldn’t try it. Again, take this for what it’s worth... second hand anecdotal info! Good luck!