From what I can see on the H&R site, the barrel length and stock are the only differences. I do not see a tapered rib on the trap barrel (picture just might not show it). I know many trap guns do not have a tapered rib, but sight changes are made in the stock. I would suspect that is how H&R does theirs. One could change from a trap gun to a field gun simply by changing stocks. I would just call H&R but their Customer Service does not seem to be up to speed on such things, per reports on this site. Time to find someone who has one in stock and ask some questions. JamesIII