The forearm is the front part of the stock, under the barrel, that your NON-trigger hand holds.
The serial number is found on the under side of the gun before the forearm.
want ad, gun show, gun shop
Forearm- or sometimes, forestock.
From your description,I would say that you have a Model 72 Crackshot rifle that was made from 1972-1989.
Deff a sniper rifle
remove pin from end of magazine tube at barrel muzzle, pull magazine tube from forearm, forearm is now ready to be lifted off barrel
Try MidWest Gun Works
try e-gunparts.com or bobs gun parts, "gun-parts.com"
Basically they are the same. But a long Barrel and a long shoulder stock make a gun a Rifle.
The one my dad has uses the same forearm. It should just snap on just like it does on the rifle barrel.
To find out how old a Winchester rifle is one would need to take the rifle to an appraiser or gun shop. The gun shop will be able to look up the gun by the serial number.
This gun is a Rifle