Ericb, Welcome to my website and thanks for our question. I have been away for the weekend or I would have replied sooner to your question. As Mike said, YES, they will some of the time interchange. But to qualify that "yes", there are some ifs and buts. In general, the early model gun barrels, i.e., 219/220's, 219/220A's, that are striker fired (no internal hammer) will fit models B,C, & D. At a glance you can tell if striker or hammer models by the number of pins in the receiver. One pin is striker and two pins are in the internal hammer models frames. While the early barrels may fit the later actions, they will not cock the hammer. In the early models, the striker is cocked when the top lever is moved to the right opening the action. Models with an internal hammer are cocked by a spring loaded stud on the lower right rear of the barrel lug. This stud engages a cocking lever on the lower right rear inside of the action and cocks the hammer when the barrel is opened. However, the B, C, & D model barrel will work on the early striker actions because as I said above, the top lever cocks the striker. With this said, I have added or replaced barrels on several actions. I have only had two that actually fit in place and locked up tight without any fitting. I have had some that are so tight they will almost close, others than won't close at all, and others that will close, but have a gap between the receiver and end of the chamber that you can see light through. On the ones that would not fit for what ever reason, I carried to my gun smith and he successfully fitted them. With this experience in changing barrels I can only advise that anyone who buys an extra barrel for his gun to be aware that he may or may not get one that will fit perfectly without professional help. And, as Mike says, have the fitting done to the barrel, NOT to the action. If you alter your action to fit the new barrel, your old barrel may not fit. Also, when the new barrel is fitted, the forearm may not lock up tight on the new barrel and a new forearm assembly may be required. So far, I have only had to purchase one new forearm assembly for a newly fitted additional barrel. I hope this helps some. Best wishes, Garnett
