FINAL REPORT:
Today, 7-22-16, I received the new barrel from Remington through Mann's Sporting Goods in Pickneyville, Illinois. The bore in the new barrel was pristine, bright, and shinny. I attached the new barrel to the receiver, grabbed some ear and eye protection and a couple boxes of target loads plus a 5 round pack of deer slugs, and went out to the range.
55 rounds later the barrel was hotter than hell but the litte Wingmaster fired every round without a single problem. It was a pleasure to shoot. I stuck a skeet choke tube in the barrel and enjoyed busting some clay targets. The shotgun is very responsive, quite accurate, and produced a very slight perceived recoil. (I am not recoil sensitive) Although I haven't had a chance to pattern the gun yet, I just put the target on top of the front sight and either a little left or right with adequate follow through and easily "smoked" many of the targets.
Back in the shop I removed the barrel and cleaned the bore. There was some "wad residue" inside but spraying some Remington Bore Bright down the bore along with a bore brush got the residue out and the bore looks new once again.
Over 2 months passed from the day I bought the gun on May 17th to taking it to the range today. I am real disappointed about all of the time it took to get the little 870 perfect but I'm really pleased with the results. I'm glad that I have ample time to get comfortable with the gun before dove season kicks off 2016 hunting season.
This post has finally ended.