Firing on all cylinders

We had set out from Dinnet by mtb to get 63, 64 and 65. We bumped into JaneO in the car park and she advised doing 65 via Milton of Tullich and then crossing the river by small bridge.
We decided to completely ignore her valuable advice and do it our way (the awkward way).
Since were on bikes, we were blooming well going to make the most of them. Our route would be to climb part way up the Ballater mast road and then hike down to the firing range. Actually it worked quite well except that the range is quite well hidden from above but we eventually found it.
I presume the apparatus shown in the picture was for hoisting targets for the toffs to fire at? Does anyone know the history?
A climb back up to our bikes (bracken could make this very difficult come summertime) and a bit of a swoosh back down the track.
Stopped at the biker-friendly (and much improved under new ownership) Crannach tearoom.

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