If you can't read my writing, part of it off the page, it's a 255 gr. Bull-X SWC over 18.5 gr. 4227. I don't think Bull-X still makes bullets, this was a few years back.
This was a Keith type SWC, the target was at around 20 yds. shot off a bench. Most of the variation was vertical, probably a function of how the gun was held. It would probably shoot one hole with a Ransom Rest.
