CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.
I've got quite a bit of WC872 in my basement right now. I've been using it in 6.5x55, 51 grains under a Nosler 140gr HPBT.
With the 308 case I'd expect that you wouldn't start seeing any signs of pressure until you got well north of 210 grain bullets, but I'd like to see someone's quickload calculations before I gave it a shot. The AA8700 data showed compressed loads for 30-06 with cast bullets, but I've run into limited data for jacketed.
Machine guns are awesome until you have to carry one.