Hey guys I have a friends Browning BAR .308 Short Trac, he wanted me to look over it and see if there was anything I would suggest to make it more accurate (he doesnt know too much about guns but likes to shoot). So the first thing I did was a take down on it to give it a thorough cleaning since he said he had never cleaned it before
. Now I have everything cleaned well butt... the gas piston was caked with carbon quite badly which I managed to clean off and as I observed the gas cylinder the recess in it was almost completely filled with carbon. I scraped out a bit with a pick but i cant see to well in there and didn't want to do any damage to the inside of the cylinder. I currently have it soaking with some solvent which if I'm not mistaken isn't exactly stellar on carbon. Any suggestions on a solution, solvent or a procedure to clean this out completely? I have tried a bore brush but it didn't really do anything to the carbon. He gave me a few boxes of his reloads and he's shooting 150 gr noslers with 46.5 gr of varget. 
