Your photo depicts a Ruski 7.62mm L/30 "Lender's" gun in anti-aircraft service. Designed in 1911 and produced in 1914 this was originally intended for air defense of Russian capital ships. During the Great War they were used in the AA role; most famously on Pierce-Arrow trucks. They were again produced for their intended ship-borne role during the late 20s and 30s. The photo illustrates an obscure( at least to me )piece of ordnance that invites scrutiny.
It is carried on a transport wagon fitted with typical swing-arm supports and fold-down crew aprons; an unusual heavy base for a relatively light weapon system. This, plus the Holt tractor, the shattered bore, are items of interest. Personally, I'd like to know the WW2 theatre of operations the pic came from. Likely it is Russia, however a number of these guns were captured during the Great War, and some were given to allies( Bulgaria, Austria-Hungary ). Could this be Czech or Polish beute ?
