My only experience with a tuner was with a Browning BOSS. It worked really good.
I did seating while fire forming. Found a forgiving powder charge, per my chronograph. Dialed in tightest grouping with the tuner.
Went to cold bore accuracy tuning with powder tweaking. Pretty much done right there.
I did not like a break though. Ended up swapping to the non-break BOSS tuner, and dialing it back in. That was easy.
Probably killed ~300 groundhogs with it, and then destroyed it..
Blew off the tuner, split barrel, expanded action ring, by leaving laser pointer in muzzle (for setting up chrono screens) and firing a shot!
In my top 10 dumbest moves for sure.
View attachment 450306
The thing about the BOSS system is that is really is a system (not just a threaded break).
It's weight may have been was set per barrel profile & cartridge/timing. They use a special hard rubber bedding with it.
They seem to know their stuff. https://patents.justia.com/patent/5279200
Their system likely focuses on dialing in factory ammo (arguably the biggest potential for tuners).