I stumbled onto IMR8133 load data while looking for top burners for the 7mm RemMag. I am doing research on an old pre WWI cartridge, the .276 Enfield the Brits experimented with after they got their butts kicked ballisticly by the Boers using 7mm Mauser during the Boer War (~1899 to 1902). The .276 Enfield was a superb cartridge for its day limited only by Cordite and great recoil. WWI came along and the Brits abandoned the project and kept their .303s. Some of the original loading propelled a 165 grain 7mm bullet out at around 2880 MV. At any rate, with modern powders of today this ancient experimental war cartridge should produce magnum velocities. I am in the process of building ammunition and a rifle to do such experiments.
Although I haven't done case capacities comparisons yet the loads for the 7mm RMag should be a close starting point.
To the main topic I did call Mike at Hodgon and tried to pin him down as to availability time, and as the above post he said early next year around the Shotshow. But I got the hint that your on line powder distributor can order the stuff sooner. Further questioning of him indicated that IMR8133 will work with the 243Win, 6mm Rem, 25'06 7mmRMag and up.