Trench Firing Device?

[lithgow1918]

I remember trying to compare it to all the conversions I was familiar with and coming up empty, although it does most remind me of the howell rifle. I remember it selling for what seemed to be a fairly low price, I think under $1000 usd. I was tempted by it but out of my depth as knowledge and at the edge of my price range at the time. Another suggestion I heard about it was that it may have been for grenade launching or something of the like, and the description as I recall suggested it possible could be for sighting in artillery or something similar. The general consensus among people I shared the images with seemed to be semi auto conversion though.
Also just checked photos it was a 1913 production gun not 1914.