The 25 yard range and gunnery backstop behind Hangar 5 at No. 6 Service Flying Training School, Dunnville Airport, Dunnville, Ontario, Canada, in the summer of 2016.   The dilapidated building is called the "Butt" building, and was where airmen stood to fire small arms at the gunnery backstop.   This may be the only "Butt" building left in Canada.
<a href="//commons.wikimedia.org/wiki/User:SteveTheAirman" title="User:SteveTheAirman">J. S. (Steve) Bond</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>