Yes, a scope can be mounted on a Ruger GP100. The Ruger GP100 is a great gun for plinking and target shooting. It is also a good choice for hunting small game. The Ruger GP100 is not designed for long range shooting, but it can be used for that if you mount a scope on it. There are several different types of scopes that can be mounted on the Ruger GP100. If you are going to use the Ruger GP100 for long range shooting, you will need to choose a scope that is suitable for that purpose.