I have been competing with the 300 WSM
for 4 yrs. Top 1k rd. I like the 1-11 twist for 190-210s. However, sierra is saying that 1-11 or 1-12 will be better for their new 210s, so I would call them.
I am shooting a Broughton 1-12 with 187 Bibs (flatbase match bullet) at around 3000 fps.