Slightly different xbolt rifle but similar challenges.
Hells Canyon Speed 300wsm With factory brake.
tried various factory rounds, couldnt get much better than 1.5 moa.
did load development and seating depth process with barnes 175 lrx, vld 175s, eldx178s.....groups got better but not where i wanted.
tried h4350, and then changed to H4831sc.
tried 190 lrabs and decent but still not great. Then went to 200eldx, and i upped my reloading game with a better scale with .001grain accuracy, brass sorting, annealing, neck turning, headspace measurement, etc.
also had trigger trouble. The browning trigger wouldnt adjust below 4.25 lbs,even with the set screw completely removed. so i got the Mcarbo spring...ok at first, and then it was inconsistent...sometimes 2.5 lbs, then 3, then 3.5, then back to 2.5.
the browning trigger assembly actually looked slightly mis-aligned inside the assembly.
so i went to a Timney trigger, now 2.5lbs all day long. its a hunting rifle.
groups got More consistent.
also added a Spartan Javelin Lite bipod, groups got better again instead of the Caldwell rest.
with the 20moa rail under the Leopold Mark5 HD, i realized i needed a cheek riser, so added a Kydex adjustable riser.
finally i started focussing on technique, holding the rifle like a baby bird, firm but not tight, letting it recoil, finger placement on trigger, finger placement and pressure on pistol grip, thumb placement along right side under the bolt handle,
and now shooting .962 inch 3 shot groups at 300 yards. its been a process.
..a fun learning process, but also frustrating at times.
just gotta stay focussed on removing all possible variables.
next step is to stretch out the distance to 1000yds, but im on hold for now with the self isolation requirements here, gun ranges are closed.
total contrast to my son's Tikka T3 300wm , which shoots 1/2 moa with pretty much anything i load for it. Still went thru the basic steps of load and seating depth development, but finding a satisfactory solution was much quicker.