I just got the washer today at the local hardware store (.29 cents!) and a second washer in case the first one isn't quite enough. But it was too late in the day to go out and do any firing to test it out

I'll definitely give you an update, wish me luck!

I could see a really faint mark on the barrel where the screw looks like it went thru too far and touched the barrel... Is this where the problem lies? That may be my biggest problem?