Geo, I'm not aware of the small htl "bridging" and causing rings or bulges. Several people I know have safely shot #9's through .410 and 20 gauge Savage 220 A and B, I'll ask around further. It hasn't been an issue on my Savages in either .410 or 20 gauge and they are FC. Larger non-compressible shot, 2, 3 and maybe 4, can jam shoulder to shoulder and ring older barrels, but I understand that the 9's "flow" without bridging. I don't believe there are commercial shells available in 9 that are steel, tungsten or unobtanium. A choke manufacturer told me that Federal Flite Control wads are oversize in one-particular modern barrel that is slighly undersized and have caused issues with bulging, but I don't recall the gun brand or size shot in the FC wad. No one, especially me, will warrant or guarantee that it won't happen with smaller shot, however.
Gil
