I measured my T3 superlight .30-06 and my T3 lite in .338 win and the barrel taper is the same, just the flutes in the superlight and 2" more barrel on the .338 win.
There is no info on the web that I can find, it appears to be a special makeup for Sportsmans, your best bet is to call your nearest Sportsmans Warehouse, they will ship one to an FFL. The superlight is the same as the lite just a fluted barrel, which saves a few ounces. The superlight also has a very fine satin finish on the barrel, as opposed to the bead blasted look of my lite. Not sure if that's just because the came from different years? I would guess if you found a Sako that had a fluted sporter weight barrel - it would be the same one that's on the Superlight.
