[2563]

I think you need to remove the forend, take the barrels from the action and post all the marks found on the underside. If you don't know how to do this then do nothing so as not to injure the gun. These marks are called proof marks and will tell us the country of origin. May I ask how you know it was made in 1933?

I am not sure what language the inscriptions are in but my guess is Italian which fit with the proof house in Brescia. Looks like it has barrels made from Krupp Steel and was proved with Walsrode powder (which I might add is a turn of the century powder). Malino may be the maker.

 

[2563]

Looks like you do have a Italian shotgun but I have no information on a maker by the name of Malino. I hope someone else can furnish you more information.

" Crown with shield below crown crossed rifles in shield" Mark of the proof house at Gardone.
" 20.3 " is the diameter of the shell rim in millimeters
18.5 is the maximum bore diameter in millimeters
" crown fino crown" Final proof in the finished state (gun)
"psf 41" (polvere Senza Fumo) Shows the gun was proved for smokeless powder

 

[2563]

Crown would be right for a 1933 date.
Barrels were made in Essen where the Krupp factory was located.
WALSRODE was a common European (Germany) smokeless powder.