GlassLakeRon,
I spent considerable time a few years ago trying out various sabot slugs in my Tracker II. I found the BRI type slug available from Winchester and from Federal gave me the best accuracy along with the most tolerable recoil at 100yds and under. Even so, I had my barrel ported at Magnaport to keep the fore end from jumping out of my hand, and added a mercury recoil reducer for better balance and recoil management.
I settled on the Federal Power Shok Sabot Slug, cat. # F127SS in 2 3/4". This has the BRI style slug, and PLENTY of knockdown power. I bought 2 cases on an auction 3 yrs ago. This was a whole lot of "overkill"

, since after the initial period of getting acquainted with the gun, I now only shoot 5 or 6 rounds a year in addition to the 1

that I need each year to bring home my deer.
I thought the 500 shells that I bought to go with this Tracker II might outlast my using the gun, and so it may be!!!
Here is the link for that slug, take a look:
http://www.federalcartridge.com/ballistics/Ammo_Search.aspx?act=choose&firearm=5&s1=1