I shot the Walker today, 75± balls (bag and a half, I didn't count them), and the forcing cone is a little gunky, but just the throat. Fired mostly 45 grains Pyrodex with cornmeal filler, topped with 50/50 beeswax/olive oil lube.
http://i613.photobucket.com/albums/t...l/DSC03318.jpg
Here's a shot from the breech end. Only cornmeal in there.
http://i613.photobucket.com/albums/t...l/DSC03300.jpg
You can see that it's pretty clean in this shot from the muzzle end.
http://i613.photobucket.com/albums/t...l/DSC03307.jpg
But it looks like that after only one cylinder too.
The cylinder is still ready for 75 more. The Walker keeps the cylinder face blasted pretty clean.
http://i613.photobucket.com/albums/t...l/DSC03293.jpg