Here is a WW1 "Antiaero" sighting attachment for a Carcano rifle that in theory allows a shooter to properly lead a flying target. It clamps onto the nosecap as shown. I believe this was a complicated system - the 12 page instruction manual is best enjoyed if you have a degree in geometry!
I'd like to know more of how widely this was produced. I can't imagine it was too popular given the variables involved in getting consistent hits on flying targets... like the ability to estimate range and target speed just for openers. Then consider things like a steady rest and all the nuances of trigger control.
I'm sure a belt-fed MG on a dedicated AA mount was quickly discovered to be a much more efficient and effective measure.
The astute forum member will soon notice this device seems to be in VG condition. That's because it's a recently made reproduction. A good friend in Italy told me he had one for a display, and I asked for the seller's contact info so I could also have a display. My friend sent one and a trade was made.
So be VERY careful when you see "original" Carcano AA sights advertised for sale. A shyster could easily bury some in the back yard for a few months to artificially age them to be sold as originals.
I suspect it won't be too long before they appear on the Euro auctions and eventually here.
A gentleman in Germany sent small details of the original such as screw size and metric thread pitch to help expose fakes as they appear. I have a photo of an original & there are differences... that the unsuspecting might not perceive.
Ask before you buy!
In any case, it's not a common accessory at all and is shown for your reference.
I'll post a pic from the instruction manual as soon as I discover how to lift one from a zip file. My Italian friend sent a copy of an original instruction manual & a prominent collector in Germany sent me the tiny details for use in exposing fakes.
The Carcano collecting community is small but close-knit!
Good people, every one I have ever met!!
SW