Cannone da 7 BR Ret. Camp. (Bronzo Rigato a retrocarica campale.) Adottato nel 1874 e rimpiazzato nel 1904 dal cannone 70/A. Most likely gun to be deployed at Adowa. (No known manufacturer, but it looks similar to Krupp 7.5cm for conversion.) http://it.wikipedia.org/wiki/7_BR_Ret._Camp.
Ordnance BL 10 pounder mountain gun was developed as a BL successor to the RML 2.5 inch screw gun. It looks very similar to the RML 2.5, and it is likely cover by Minifigs 7CA with the distinctive long barrel (as opposed to the short barrel of Minifigs 3CA.)
Armstrong Breech Loading 12 pounder 8 cwt, later known as RBL 12 pounder 8 cwt, was an early modern 3-inch rifled breech-loading field gun of 1859. This is probably not Minifigs 6CA, but an early version of the 12 pounder. At a later time, three type of 12 pounder are documented: 6 cwt (RHA, East Africa), 7 cwt (superseded by the 15 pounder in 1895), QF 8 cwt (2nd Boer War, Gallipoli, East Africa) http://en.wikipedia.org/wiki/RBL_12_pounder_8_cwt_Armstrong_gun
Cannone da 7 BR Ret. Mont. Cannone da montagna italiano. Ultimo tipo ad affusto rigido. Simile a RML 7 pdr. britannico. No model available (maybe a Krupp gun with shortened barrel?) http://it.wikipedia.org/wiki/7_BR_Ret._Mont. http://www.frontedolomitico.it/Eserciti/Armi/FronteDolomiticoCannone75B.htm http://www.vecio.it/cms/index.php/artiglieria/340-cannone-75b-da-montagna-7-b-ret