I wonder what the velocity bleed off is, small diameter TSS, like steel sheds velocity rather quickly the faster you start it out.
We use 5/8oz #9s in our 28ga guns at 1400fps and they hammer out farther than most people should be shooting.
Yep. I duplex #9 TSS/#7 steel in 20 and use similar TSS loads to you in 28, and it’s amazing what they will do if you can put them on the bird.