I'm a range officer, and see many, many 22 cal rifles shot here every week. And over the years I have not seen many 22 bolt guns out-shoot those CZ rifles. Take 2"-3" off the barrel, get it crowned proper.
Good reminder about the LE Wilson to be used on FIRED cases. The LE Wilson has a micrometer measurement attachment, that allows you measure exact headspace and use to set back shoulder the exact amount you choose.
Looking at the drawings, it is actually .0001 smaller (.2845) at the case mouth than the PRC. And I don't see how this can "allow" the bullet to tip relative to bore anyhow.
Built two .308's, three 6.5 Creed's, and a .260 Rem. On the AR10 platform. All are tack drivers, and all are standard rifle length gas systems. I don't understand your "weird" gas system problems. Nothing weird about rifle length gas tube.
My Criterion 20" 1 - 11 and my Faxon 18" 1 -10 fluted barrels both shoot MOA with cheap Winchester 7.62mm x 51mm M80 149gr. Aero Precision AR10 rigs that don't seem to be too heavy to carry.
Wow, that is a beefy barrel. The end of the barrel looks like it is rising out of the forend of the stock. Maybe not inletted level in the stock. Look at the last photo. Maybe optical illusion?
But, to tell you the truth, I have three 308's on the bun rack right now. And I can always get ammo for them,no problem. But they are not really a long range rifle, like some others I could name.
Who did your action truing? Sounds like they did more damage than truing: bolt would not close, had to replace extractor, they cut off bolt and rewelded. Wow, doesn't sound like truing to me. I don't think things went well for the guy doing the truing. Send it back to them and have it...
I have had some stored for 25+ years, tried some of my old favorite accuracy loads and got the same old accurate small groups! Keep it sealed and stored properly and it will last a long time.