Tikka are certainly special. The first time anyone runs a Tikka bolt, the smoothness almost begs a question, can this safely contain the massive pressures inside an expanding cartridge case? Kimber actions also raise that question when Kimber designs lightweight actions that are dimensionally smaller. I like both actions.
How much metal do we want or need around a cartridge? Weatherby has a different answer with the multiple locking lugs. Weatherby and Tikka are push-feed, something irrelevant to the long-range shooter, while Kimber has a control-feed claw-extractor, something still desirable for many of those walking out on a cool morning where buffalo are around.
I make these observations to raise a question, how powerful a cartridge is optimal or maximal for a Tikka action? Factory offerings go up to a 338 Win Mag. How about a 375 Ruger? To really up the ante, what about a round like the 500 AccRel Nyati, a Rigby case shortened for a standard long action? Or a 458 Win Mag or 416 Ruger on a standard .532" case-head? The CZ actions are rough, strong and BIG. Ruger Hawkeyes are big, strong, yet shorter. I don't have experience with the Kimber magnum actions.
Back to the Tikka, does anyone have a rubric for ranking the bolt-thrust capabilities of the various actions? Yes, all the actions on the market are safe, but how safe? At what point is there significant compromise taking place?