[4] Among the other real estate deals he made, he built the Armstrong Block, one of Calgary's earliest commercial buildings, which was later demolished to make way for the Glenbow Museum.
As a member of city council he helped create Calgary's early street numbering system and electrical lighting grid.
[10] Armstrong was heavily involved in Calgary's sport-shooting community and under his leadership the 103rd gained a reputation as "probably the best shooting regiment in the whole Dominion.
"[11][12] In 1933 Armstrong was given an illuminated address in gratitude for his eleven years of "conscientious service" as honorary secretary of the Alberta Provincial Rifle Association.
The address read in part "Colonel Armstrong has added long years of voluntary and devoted service to the cause of marksmanship, both as a sport and as a military exercise."