Here is a pretty rare French manufactured Lebel model 1886 M93 fitted with an original A.P.X. 1916 scope. The Lebel M93 used to be the French main sniper rifle during World War I. The APX scopes evoluted from APX 1915 to APX 1917.
Below are three black & white pictures, taken in the trenches, showing French snipers using Lebel M93 rifles mounted with APX scopes.
Here is a WWI Enfield SMLE rifle fitted with the scarce Whitehead mount and a Winchester A5 scope. A one of a kind configuration in the collection world but not the best sniper setup of its time, from an engineering point of view.
This Dr. W. Gérard B3x sniper scope has an uncommon transitional straight lined mount. These mounts were completely offeset to allow the sniper to aim with the regular bore. They were replaced by half deported mounts on most of sniper scopes pretty early in the war.
1937 PEM sniper scope with straight top mount for Mosin Nagant 91/30
For once, this is not a WW1 or WW2 sniper scope. This K.Kahles H/4×60 scope with side mount was part of a Nicaracuan Contract and mounted on Hämmerli K.31 sniper rifles (only 100 were ordered).
Aldis 1915 sniper scope with J. Purdey and Sons mount for SMLE
To this civilian Optikotechna Lovec 4x rifle scope was added a 100-800m meter dial and a sunshade (missing here) to make it usable by the military. This one is mounted on a SSR mount