Polished barrel COF restoration?

After several failed attempts at extrusion this week, I finally have deduced that the ABS is no longer being pushed by the auger. It could just be the fact that the existing mass of plastic broke away from the barrel when it last hardened, but I'd like to ensure that there is a much higher COF between the plastic and the barrel before I put it back on.
I believe this all started when the melt filter last became full of dust, preventing normal extrusion. The stagnant plastic hardened when I shut off the machine, and my efforts of reversing the auger to clean out the hardened material must have ruined the interior surface.
My question is, what is an effective method to create a new rough internal surface for molten plastic to grab onto? My initial thoughts are to rub coarse steel wool through the pipe to create deep scratches along the length, but I feel like there is a more effective method to do this.
I also now have the tools to machine fresh lengths of pipe from Home Depot, so a new barrel is not that much of a problem, but I would like to rough up the inside first before swapping, as I don't know how polished the insides of those pipes are.
I would like to believe that the plug of plastic is the only problem, and removing it entirely will restore the COF in the next run, but I can clearly see polished areas in the feed zone, which means the rest of the barrel is probably worse off.