Charlie, First off you need to be sure to take out any play in the receiver wrench. Using tape if you have to but the wrench needs to be snug. Then as Marcus suggest make sure you have something solid like his drill bit in place of the spring tube when you try to take it off. Now I have found a nice four to five foot section of steel pipe on the handle will allow you all the torque you need to remove it. Use the barrel clamp too in the vise. Make sure the screws are tight and that it is firmly seated in the vise. Then have at it. I had an early Winchester like this and doing what I suggested made it easy to remove a bad barrel. The new barrel same time frame as the old one would not go on till I had to have a machinist remove a small amount of barrel and receiver.