The NRA was founded by Union officers because their troops could not shoot well. This quote is directly from the NRA's on history.
"Dismayed by the lack of marksmanship shown by their troops, Union veterans Col. William C. Church and Gen. George Wingate formed the National Rifle Association in 1871. The primary goal of the association would be to "promote and encourage rifle shooting on a scientific basis," according to a magazine editorial written by Church. "