I am considering building a 7mm STW using my current LA Savage. The max OAL that will fit in the magazine is 3.425". Can someone run that through Quickload to see what kind of velocity I can expect with a 154 gr Hornady IB in a 26" barrel (Federal 215 primer, Winchester Brass, probably Retumbo or H1000 powder, 1:9" twist)? How would a standard 7mm Mag compare?

Loaded to the same pressure and OAL the STW will give you about 100fps over the 7mag. Loadtech calls the STW with that OAL around 3350. The 7mag 3265. That short OAL is costing around 75fps

Thank you for running the data. It is much appreciated.