A question about animations

Hi. Im making a pistol in 3d max. It’s completly done, but i have a problem with anims. I don’t know how to do a movable slider. I rigged it and skinned it with a special bone, but reciever is stay in “air”. Other parts are movable, except slider. I don’t know what to do. Help me,plz.

I’m no expert, but I had the same issue years ago and my solution was to bake the whole animation since connecting slider bone to the rest of weapon would break the animation.