As there seems to be general agreement on torque values, I am going to take a stab at describing how I would go about torqueing down the action screws on the HW50s specifically.
I believe there are two what I call action screws on this rifle, one at the front of the trigger guard, and a second at the front that threads into the bridge under the cocking arm. The small screw at the rear of the trigger guard only holds the trigger guard in place, and plays a minor, if any, role in securing the action to the stock. Given that the goal is to obtain uniform seating of the action in the stock, the action screws need to be tightened alternately and in small steps. The trigger guard itself acts to distribute load for the rear action screw, the front screw should have the largest washer possible placed between it and the wood to reduce wood compression. A torque wrench and bits that provide a good fit to the screws will make the job easier and more repeatable.
Begin by running all three screws in then backing off a quarter turn to leave them a bit loose. At this point I turn the rifle barrel up to make sure the action is seated back in the stock. With the rifle upright I begin tightening the action screws in 5 in-lb increments starting at the rear screw. Once the screws have been tightened to 10 in-lb the rifle can be laid down or left upright for final tightening as you prefer. Continue tightening until the final desired torque is reached on each of the two screws. Since the HW50s is not a heavy recoiling rifle, 25 in-lb might be enough to hold things firm and keep screws from loosening. Once the action screws are tight, I tighten the rear guard screw just enough to keep it from working loose.
On a new rifle, it is often the case that screws will need to be retorqued before each use several times until the action and screws fully settle in the wood. During this period, I do not use Loctite as I am concerned it may affect my torque readings. After two or three rounds of retorquing, it should take no more than a slight rotation of the screw to bring torque back to the targeted value, less than 1/8 of a turn. If the screws won't hold torque, you could try a higher torque value. If that doesn't work, something will need to be done to reduce wood compression, bigger washers or some type of bedding. Once torque seems to have stabilized, the screws can be removed, cleaned, Loctite applied, and then reinstalled and torqued down to the final values.
