You’re not really giving us much information to work with here. Are you having issues with the code part of it, the animations, or something else? At the most basic level, an ADS system is just a pair of animated arms with a gun attached to it that you attach to a camera. When you animate your arms, you want to make a set of animations for the hip fire and the ADS. With the ADS animations, you want the sights of the gun to align with the center of the scene in your 3D software. When you attach the arms to your camera, the sights will align with the center of the camera. Then you shoot your projectiles or line traces from the center of the camera.