First remove the extractors and clean , see that they push in and out smoothly . If they do and there is still a problem then take the gun to a competent gunsmith . Dickson ejector work can be a problem and it is quite easy to make it worse if it is not approched correctly . There are several things that can go wrong but it is all inside the gun mechanism .It is also a fact to be faced that putting it right can be expensive as parts may need to be made .