That new link I put up does kind of use the sensors to track it. You can see they have mounted it to front of the gun. Also you can see in the onscreen display only one vive sensor is activated so it is treating the gun as one controller only.
@adrock I totally agree with what you are saying. And Jes. It is a challenge to overcome. I wouldnt want to miss the more engaging moments of picking up magazines, having to cock the gun etc. But at same time I feel that really I am just holding a rifle with one hand.
See video though with the quick release magnets you mention. I was telling Jes about this last night. One guy band making this stock. Think it looks pretty neat.