Simon

I use a Sealey 2 - 10 nm screwdriver type Model STS100 that comes with all the common sockets, I use it for all my rifles .22's and full bores. The scale is a bit basic but is easy to read the full figures i.e. 3, 4, 5, etc, and is easy to judge the between for quarters. Its cheap and accurate.

If you have your rifle serviced by a factory tech, most just do it by a "calibrated" experienced hand.

More detailed torque wrenches that show a scale to 0.1 cost as much as your rifle!

And finding out what torque to use is another subject, and the order of tightening. And beware changing you action screws for pretty stainless ones, which I see a lot, they are often a lower max torque than the correct torque for the rifle.

Have Fun