Accurate 300 win mag CIP mags worked great for my 30 Sherman but I had to tune on the feed lips.
action is a Curtis Helix in a KRG chassis. The same mag that are tuned on also still feed 300 win mag as well.
no experience with the MDT mags but interested in hearing your report.
Late to the game but just ran across this thread. Hopefully the MDT's are working for you. I've used them in a CA and with a Badger action and have had no issues.