[C#] How Can I Change A Int On A Script That Is In Multiple Objects From Another Script

I have a script named Gun and it has a int called rpm. It is in multiple objects. I want to add a number to rpm to all of the objects it is in through another script. How would I go about doing this?

use static variables so in the gun script:

public class gun : MonoBehaviour {
public static int rpm;
}

and to access and use it from other scripts

public class OtherScript : MonoBehaviour {
private int otherrpm = gun.rpm;
}