Weren’t pretty much all weapons military weapons when the founders were, er, founding? Which makes the question, oh I don’t know, silly?
Actually, rifles were primarily strictly for hunting.
Rifles took too much skill and time to load for use in the combat tactics of the time.
Washington was an early user of Guerilla tactics and the use of snipers. But in the day, this was considered ungentlemanly. Firing from cover was cowardly.
But Washington had little choice being out gunned and out manned and fighting an enemy with far greater financial resources.