hey ive just started to have a problem with the barrel leaking

its just when i have the billy wing bolt in too

Is the leak coming comming from the center of the bolt or around the outside of the bolt? If the leak is from the center of the bolt replace the 014 on the top hat. If it is comming from around the bolt replace the 017 on the can. I personally recommend that you change the 014 and 017 on the top hat and the 017 on the can when installing any new bolt.