Depends on your definition of accurate, and at what range. I shoot a few Pennsylvania rifles, and they can group in a bit over an inch at 100 yards. At 500 yds, it would be a very different matter. They were considered accurate enough to hit a man at 300 yds under the right conditions. They are less accurate than modern target rifles that can hit an apple at 500 yards.
You will have to define "sniper rifle". There is no meaning to that term, other than an accurate scope mounted rifle. That includes most hunting rifles.
Rifles and shotguns are separate types of firearm. The Kentucky Long-Rifle was as its name implies a rifle, not a shotgun.
Kentucky Rifle - 1955 is rated/received certificates of: Iceland:16 Norway:12
the rifle
The address of the Kentucky Rifle Foundation is: 17 Odin Ct, Columbia, SC 29229-6510
The M16 is an assault rifle that is a .223 caliber / 5.56 mm. like any weapon it is only as accurate as its shooter, <><><> It can be very accurate.
You will have to define the term "Sniper rifle". It could mean anything. The only TRUE sniper rifle is a rifle issued to a sniper. They are simply rifles that are capable of long range accurate shooting. The rifles used by US military snipers during the Vietnam was were simply civilian hunting rifles with decent telescopes.
the Kentucky LongRifle
That depends on the tolerances of the rifle and the quality of the ammunition.
The Kentucky Long-Rifle is known alternatively as the Pennsylvania Long-Rifle, and the American Long-Rifle. Being from the Commonwealth of Kentucly the author of this answer asserts that Kentucky Long-Rifle is the one and true proper name. Now, as to the meat of the question. This long pattern of rifle first appeared in Pennsylvania as a product of German immigrants to the American Colonies. Due to its capabilities the gun rapidly proliferated from there. This type of firearm came to be known as the 'Kentucky Long-Rifle' in later years for a number of reasons. The most important of which would be that in colonial times the men of Kentucky had a reputation not only as hunters; but as Sharpshooters wielding this distinctive family of long-rifles.
@ 2 MOA
50 caliber