Older thread, but yes, I got much better accuracy out of my 6.5 Grendel when I moved from a low mass carrier to a full mass carrier, but it got even better when I added a Tubbs carrier weight. I still use an adjustable gas block and tune the gas accordingly. Usually not shooting this offhand and can't really tell any difference in the recoil.
You can tell the bolt stays locked longer. I can't rechamber fired brass from the low mass carrier, but it rechambers just like it was fired from a bolt gun now.