I’ve got a Sendero in .300 magnum, McMillan stock, great rifle. Hyperdyne flash suppressor.
Off track here,,, I picked up a Mark V 30-378 with a McMillan stock. Been loading 100 grains RL22 180 X bullets. It shoots ok, but nothing spectacular,(I have a 40 year old cheap Savage that shoots better). Are you happy with the McMillan stock? Do you think it really makes a difference?