Sure why not, not convinced that it was built for just blanks.
Whatever it was made for originally, at this date only 12 ga. blanks can be used in it, since barrel is under 18" and overall length is less than 26".
I see no provision to handle recoil which is another reason I think this was made to fire blanks.
It is a pretty neat job however, especially the breech design. The closure and locking aspects of the design mimick the Brown system, which was actually patented by Lavigne.