Ok The "new to me" barrel i just purchased from a pawn shop that was identified as a Moss 500 28" Field barrel, does not fit my Moss 500? Stock, my Moss is 8(7+1) shot with 18.5" barrel. It seems that the mag tube is too long to allow me to set the barrel into the action, does that mean that I need to change the mag tube to a 6+1? Also as a side note, besides the box and receipt, how do you identify the shotgun and replacement barrels as being for the 500 series? Although the stamping on the barrel identifies the correct gauge and Mossberg Address, I don't actually see the MossBerg name printed anywhere on the barrels or even the gun action. I do remember the box for the original gun, bought new, saying Mossberg, but other than that, how do you clearly identify except by seeing the MossBerg "Look".