If this has already been discussed pls advise, have not visited in a while. The piece at the link is interesting not only for the history, but for an unusual characteristic. On the outside it is nearly identical to any of the Model 1784 Spanish Mountain Howitzers, but internally it is a gun with no chamber whatever. Another difference between this and the howitzers mentioned is that this one has no trunnion markings whatever. On the howitzers, with a few exceptions I've seen, there is no marking save "No. XX" for a foundry number stamped on the right trunnion. All such numbers I've seen or had reported are either two or three digits. Also on the trophy gun, the cascabel knob is slightly very teardrop-shaped as opposed to the nearly perfect sphere on the similar howitzers. I think this is clearly a Spanish weapon despite the auction writeup mentioning "Portuguese."

Has anyone found documentation on this model of gun?
Are there any other examples that have been physically verified to be a gun and not a howitzer?
It seems that the gun number would be the number on top of the breech; if so then what is the number "20 3" stamped on the upper muzzle face? It is not simply "203" as in the auction catalog, but clearly "20 3" as if two data fields were intended.