I'm having a 7mm STW built and cant decide on what twist rate to use. I will mostly be shooting 140 gr bullets but want to be able to be a little flexible in this. Any suggestions?

Frasier,

I think my Sendero has a 1 in 9 and it shoots the 140gr.NBT into real tiny groups.

1 in 9 is the factory pitch but 1 in 10 works fine with 160 gr bullet with max velocity 1 in 9 is use byRemington for 7.08 too !!!!.

depend what flexibilty you want and what throat you have or plan to have , if you plan to shoot top end of heavy bullet as 160/175 best is to have a deeper throat to avoid deep seating ( 7 STW is a short neck case ) but check your OAL for your mag
if you stay in 140/160 regular throat work fine

my persoanl choice will be 1 in 10 with 140 Scirocco and 160 Partition for hunting and 162 AMAX for shooting paper

good shooting

DAN TEC