Beefa, Do a search for BRI in this forum. Look at my post, "TRACKER II SLUG RANGE UPDATE......"
This is for the Winchester 3" BRI 1oz. slugs. I later found the same slug in a 2 3/4" shell from Federal, cat # F127SS, that actually shot better in my Tracker II! This shell gave me 3 holes touching at 50 yds, and a 2" group at 100yds, with 2 of 4 holes touching.
The price of these may be a little less that other sabot loads, if that matters. You may be able to get a good price on the Winchester BRI slugs (XRS123) or the Federal load (F127SS) at cheaperthandirt.com
This is a 1oz sabot slug, and I found it VERY manageable compared to the 1 3/8oz Brenneke loads or Lyman cast slugs, even with a mercury recoil reducder and Magna-Ported barrel.
Have fun!