No problem - it's not a hijack at all
The height for 10m air rifle target isn't mentioned specifically; however we shoot as do most other clubs as far as I am aware, on the same target changers so I assume that the centre of the central target of the 5 is at 1.40m.
http://www.sintpietersroos.com/catal...frules2017.pdf pages 229 - 230 refer
Hope this helps.
Mike.