You’ll be able to tell… if your groups start to open up a little, let it cool… if it’s too hot to touch, let it cool for awhile.
The tikkas I have owned have not been temperamental to heat (within reason)
Go shoot 3, take a couple minute break to mark your hits on the target, go shoot another 3, rinse and repeat and keep tabs on how hot the barrel is, that will tell you
Practice quality shots rather than quantity of shots, I promise it’s easy and straightforward. I like shooting in the cooler part of the day so it cools things down quicker between shots, and leave my bolt open between groups to dissipate heat faster (not sure how much that helps but it’s intuitive)
I generally bring more than one gun when shooting and let one cool while shooting the others… a rim fire is great for that drilling shot mechanics between groups with my bigger rifles