Take it to a competent gunsmith.
By a good gunsmith.
Use a punch and tap it across the barrel. Its a dove tail joint.
To remove the forend on a Winchester Model 290, first ensure the firearm is unloaded and the safety is on. Next, locate the forend retaining screw, usually found at the front of the receiver, and remove it using an appropriate screwdriver. Once the screw is removed, gently slide the forend forward off the barrel. If necessary, you may need to pull the forend slightly to disengage it from any retaining clips.
Winchester 190-290
Best left to a gunsmith.
Leave this to a gunsmith
Brownells carries just about any gunsmithing tool there is.
The Winchester model 290 belongs to the Winchester 200 series of rifles that were introduced between 1963-1965.The model 290 was discontinued in 1976.
your Winchester model 290 was made as a group of models including the 250,270,255,275 and the 290.these were made from 1963-1976,with the model 290 being the last model made.
your Winchester model 290 was made between 1965-1973.
the best I can do is say that your Winchester model 290 was made between 1963-1976.
remove the buttplate screws, and the buttplate. In the large round hole in the stock is the stock bolt. That is unscrewed to remove the stock from the rifle.