Thank you everyone for your advice, and kind and encouraging words. Sorry it took me so long to reply. I've been out of the country on business for a few days.
The rifle was purchased from a reputable gun smith as new and unfired. It had the factory barrel removed by the smith, who had planned to rebarrel it and turn it into a Palma Match Rifle. I requested that he re-install the factory barrel (since they are usually fairly accurate, plus I saved some much needed $$$'s by doing this). Tikka/Beretta claims that the chamber is a match chamber with tighter tolerences than a typical factory rifle (on a phone call with Beretta). Apparently the chamber is not really all that tight. Oh well. I plan to practice a lot and learn as much as possible about reloading and LR shooting on this barrel, then rebarrel to something like a 260AI.
I got the itch to reload the other day, so to prove to myself that I could trust the brass, I 'opened' a piece up. Here is what it looked like:
From there I used some of my unsorted BHA brass (until the Sinclair primer pocket uniformer arrives). I applied a good amount of force with the press to prime the brass with the primers flush to the case head. I used IMR4064 powder. The Sierra reloading manual showed 43.4 grains to be the 'max' load for the 168 gr. BTHP, while the IMR reloading book showed 45.9 grains to be the 'max' load for the same bullet, HMMMM??? (any advise on what to do with this?) I started low and worked up to as high as 44.0 grains of powder, so far, with no apparent signs of excessive pressure. The weather was windy, cold, and gusty with winds around 15 to 25 mph and shifting between 7:00 and 10:00. I tried to pull the trigger when the wind felt similar to the previous shots. All recorded shots were at 100 yards. Here are some of the results:
Here are some 'baseline' groups that I shot with factory ammo on the same day:
It seems to me like 42.7 grains shoots well, as does 43.2 grains.