Not that this is the be-all end-all source of information, but I do find it interesting to note that out of the top 150 PRS/NRL shooters in the county
not one of them used a 6.5x55 or 6.5x55 improved in 2018.
Welcome to “What The Pros Use” 2018 Edition! I recently surveyed the top ranked shooters in both the...
precisionrifleblog.com
A 6.5x55 is not a bad round, but the fact that no one has chosen it is a pretty strong indication that it's probably not the right round for PRS.
@Westernhntr If you want to turn your Tikka into a PRS rig for getting started out, I would suggest something like a KRG Bravo chassis if you're on a budget or MPA chassis if you've got a bit more $$, run conventional AICS short action mags, and pick one of the commonly used PRS calibers listed in the article above.
I can tell you that in your neck of the country the top competition shooters are mostly running Dasher. The Idaho NRL match was just a week ago and out of the top 10 shooters I believe there were at least 7 shooters running some sort of small 6mm based on the 6BR brass (one of them was a 22BR). I won a PRS club match in Eastern WA the same weekend running Dasher with 115 DTAC's at 2810fps. Not necessarily suggesting you go build a Dasher, just giving you insight that a big case 6.5 is way more than you need to be competitive, and would actually probably hinder your performance.