What velocities are you seeing? Are you shooting suppressed? I doubt it is annealing. More likely as stated previously:
3-Light charge on load.
4-Suppressors (much more of an issue with semi-auto and yours is a boltgun).
These "somethings" can work together to leave some smokey cases. Your...
No. I could not find 109s that did not cost an arm and a leg. I got a few k of 115s. If 109s ever come back at reasonable prices with some consistent stock I might go back to them.
I would give N555 a good look. Very cool burning powder, easy on barrels and temp stable. Of the VV powders, N150, N160 and N555 are going to be your best options.
You have a point. Some years back the Hornady manual had 40.8 or 41.2 as max for 140 and H4350. However, their match 140 ammo had a recommended reload of 41.5 of H4350 printed on the box, lol. I think they stopped printing load data on ammo as it did not jive with manual data. I have yet to...
Noise. I run a CPS and get plus or minus .001 variation at most. The biggest thing I was able to actually measure was SD. Nothing else changed in my testing. SDs went from around 8-9 to 4-5, everything else was the same. That was a .002 crush on primer and that is where I run everything. I...
Did you inspect cables / connectors for cracks? The tines on those cables brake / crack real easy and casue those issues. If it is not cables it is likely the motor. But cables are the most likely issue.