Plane simple dont use oil in the barrel.
Use the rod and a clean patch and get it clean. Do that untill the patch comes out white.
Dont forget to turn you hopup off befor.
And if you are really willing to use oil in the barrel just use a clean patch and put some on it (2 to 3 drops) and repete phase 1
then after use a clean patch to wipe the excedent.
Never put oil on your hop bucking. if you effel that you have a bad hopup just change it's a 8$ peice. No oil will ever make a hop rubber work like a new one.