Demo on fitting a YoDave Tikka T3 trigger spring, a nice upgrade on a great factory trigger.
For further adjustments to trigger release pressure, set to your liking by adjusting the screw in or out to suit
Recommend hitting the butt of firearm fairly hard with a dead blow hammer once you have set trigger, see if it releases - if it does adjust and re-test up till it doesn't.
You need to do this to make sure the sear does not release as your firearm will be unsafe.