it is either a m1909 or an m1917 depending on the caliber.
either way its a colt model that has had its barrel shortened. It started as an earlier model,m1909 in 45lc, that was modified to take the 45 acp cartridge that was in use for the model 1911. There were not enough Remington 1911s so they also used these. They didn't replace anything they filled a manufacturing void out of necessity. Very cool revolver indeed. btw the Remington 1911 was also made by companies such as rand typewriter co, and even Singer sewing machine co. during the push for armament.
They didn't call these trench guns, that name was given to 12 gauge shotguns shortened and fitted with bayonets. Remington model 10s or Winchester model 1897s. which btw the Germans hated and even tried to get them banned from use.