That is good news. I have a barrel on order, but in 338, for your heavy 338s (along with Cutting Edge, etc.). Don't think my rifle is capable of being a switch barrel, but if it were one would be a 375 Lapua. The brass is so good I don't want to stray from it. So I'm toying with a Mausingfield and a gain twist 375... However, the wait for a gain twist in that bore size is longer than some of the fish in tales I've heard. This would be for a carry gun as well--with a shorter lighter cut barrel of course.
Sure interested in your upcoming experiences with your "test platform." Thanks for responding.