I got to fire the early M-16 in USAF bootcamp - well worn rifles that I am surprisd allowed me to actually shoot a decent group at 200 yards. I was not experienced with peep sights at that time and hated them. Now I am a believer and have many rifles (mostly rimfire) fitted with peep sights.
In my experience, the term "Sweet Sixteen" applied to the 16 gauge shotgun. Loved my Rem 870 in 16 gauge for squirrel hunting!
PROUD TEA PARTY EXTREMIST!