Contact these guys. They have all of the parts, knowledge, and experience fixing these guns that you will ever need. Very nice people.
I am guessing a lower barrel spring broke. Very common problem. Especially when the piece that broke off the spring gets moving. These have the Perazzi style, clip type springs in them. They are boogers to get in and out. Somewhat detailed disassembly required. They sit vertical against the back of the receiver, and require a sequence of disassembly to get at them. One of those that if you have done 100 of them, they are a piece of cake. Well, not that bad.