I just had a donor a couple months ago make me wonder if I was going do damage the action.

It was the 3rd action I did(10 accutrigger round back), and way tighter than the others(both 110 pre accutrigger flat back).

I tried heating the nut. Let kroil go at it for 24 hrs.

Ended up applying a lot of force to things that I really should not have. I was almost expecting a twisted action. Luckily everything worked out.

In hindsight, I should have cut the nut, or barrel and nut. Best advice, if applying torque to the receiver, stay as close to the barrel as you can. The farther back you go, the more likely that it will twist.

Best of luck too you.
Adam.