Did you take out the side screw and pull the crane and cylinder off of the gun? My model 18 gets a little tight after about 100 rounds and a good cleaning and lube of the ejector rod and the sleeve it goes through fixes it. When clean it will move 1 1/16 inches when pushed to eject the casings.
I recently bought a Model 28 safe queen that hadn't been cleaned in about 15 years. After I cleaned it as described above, it was good to go.
Hope this helps.