I believe the 7MM STW (94 grains approx) and the 7mm-375 (96 Grains approx) both have very similar grains H2O capacity so the load data should be nearly identical. I would certainly feel safe using starting loads for the STW for load development. Depending on AOL of the cartridges the 7mm-375 would probably have even more useable case capacity in a given action due to its shorter case length.