How versatile are the Model 1300 barrels? Will they fit earlier or different models?

The Model 1300 barrels will fit Model 1200 receivers, but 1200 barrels will not fit a Model 1300. Model 1400 barrels will not interchange with Models 1200 or 1300 barrels.

The Model 1300 Defender barrels will not interchange with the 1300 Field models and vice versa.