Why the change from dasher to bra? Anything in particular?
No change, running both this season. Dasher barrel has ended up being what I've shot at the NRL matches and will probably shoot that barrel at the NRL finale.
Usually the decision between barrels ends up being made on which caliber I have brass processed for and ready to load. Dasher is 27" and running around 2940 fps with a 105 hybrid and 32.0 Varget. Speeds are so close there's not really a ballistic advantage to one or the other.
I've got a fresh Dasher barrel in storage ready to go, and just got email notification on another 6BRA barrel that my gunsmith finished. No plans to abandon either caliber.