I loaded ten rounds like this:
Brush wad,cork,slug:
Velocity was as expected. Target at 50 meters for starters. Enlarge so you can see it.
Group size was about two feet, slugs were keyholing perfectly:
I had similar results with Svarog Zveroboy tailwad fullbore slug the other day. I tried it with IC as well, no good. They say it is for smoothbore. Oh well.
I guess these Grizzlys really are for a fully rifled barrel. Ideas?