Re: 7mm stw fans
Welcome to LRH!
You will find lots of 7STW fans here (myself included). I haven't worked with the 140 gr TSX but I would think 3400 fps or maybe more is attainable out of your barrel length.
I tend to be a little on the conservative side with my loads, so you may get some higher numbers from some of the other guys.
Lefties are the only ones in their right minds!
(and I ain't talkin' politics!)
NRA Life Member