For what its worth, I've used one piece sportsmatcm mounts on my weirauchs HW77 and HW97 for years and no problems and no scope creep.Don't need locating pins.
The HW77 has a fixed one piece used since 1982,and the HW97 for 5 years using the adjustable one piece mount.
The adjustable is a more precise way to set up a scope and leave scope turret adjustment to a minimal in its central positions,
Hope it helps.
Fighter against the 'Dark Arts'
Dark keeps moving in on the day.
Steadily going downhill faster!