There is no sense in argueing wiyth Dan on this one, his mind is made up, not sure of what though... there is at least one period refernce to "smoothrifle" when a trader was trying to sell them on the frontier he mentioned they were quite popular back east.
There are references to smooth guns of various types in lots of places. There is a citation in "British Military Flintlock rifles" of rifle stocked smoothbores ("very small bore" as I recall) and rifles in stock at a trading post circa 1750-55. Book is away from the computer. Bailey also points out the vexing tendency of writers of the time to use rifle and gun interchangeably not matter if the barrel is grooved or not.
I tend to get bent out of shape with the constant telling of things such as how someone shot wonderfully with a SB at 200 yards. Etc etc. If you like smoothbores or someone at the last shoot did good with one fine. But posting someone shooting well with one at 200 yards when the target is a pile of dirt is just silly.
I have been testing a 42" 50 cal smooth rifle. I shot it fairly extensively with various powder charges and 3 ball sizes and 2-3 patches. 25 and 50 to 60 yards.
Typical group at 25 benched.
In fact its about as good as it did with 490 and 495 balls and powder charges of 50-60-70-75 grains.
I expect the grooved barrel to do as well with 30-40 grains of powder perhaps even 20. I have shot grouse with a 50 with 20 grains of powder years ago.
This is 4 shots 16 bore 80" twist with 140gr of FFG same day shot while the smooth gun was cooling. Not really worth @!*% but better than the 50. I have done better with it at 50-60 yards. But it was a "control" of sorts. This gun is not a lot of fun off the bench.
100 gr of FFG Goex at about 55 yards with the smooth rifle. This is typical, close to the best but far from the worst with various ball sizes.
This is 3 - 3 shot groups with the 16 bore but on a different day.
Rifle really does not like a wad of any kind under the ball Feltan bluestreak shotgun wads do the same thing.
Work since has shown that I can shoot 2" or less with this rifle at 50 yards reliably.
Why 60 yards? Because we no longer have an outdoor range here. So I shoot on BLM land. Thus my 50 yard is sometimes 52 or 55 or in this case 60 if I forget to take the laser out to set the target up.
The SB barrel will kill a deer every shot at probably 75 yards if you are shooting from the bench.
The problem lies in the shooting conditions. Now I know a lot of easterners shoot from stands and blinds and have chairs and rests and all that. Hunting "free style" means that the bullet does not always go where its pointed due to shooting position etc. thus shooter error that would make a slightly off shot with the rifle makes a "worse" off shot with the smoothbore if all the errors stack right.
Also note the powder charges. The SB likes a lot of powder 90-100 grs of FFG so far. The rifle barrel fitted to this gun will shoot smaller with less powder. Testing has been very limited with the rifle barrel right now but the sights are as identical between the 2 barrels as could be expected. I did shoot it at 300 awhile back to see if General Fraser could have been killed with a 50 cal at 300 yards. He could have. The only other group I have photographed is of about 10 shots while moving the sights. I need to color the rear sight and then do more testing but its hunting season and the windy season as well...
I will likely lap/polish the SB barrel since I think its rough for the first 4-5 inches down from the muzzle and this could be a problem, or not.
I see accuracy as having the bullet hit where I have the sights when the trigger breaks. Inaccurate firearms are a disappointment.
From reports I am confidant that 20 bore smooth with buck and ball will take deer, maybe too many if they are grouped a little too close together. But I have just been burned too often. 3 times on game as I recall. One maybe me but others just from having the wrong tool for the job. I actually gave up on smoothbores for shooting a ball circa 1980. But twice since then I have "re-tried" the smoothbore. A 20 bore fowler a few years back and then buying the smooth barrel for this rifle just as I was getting it finished.
To go back to the "can kill a deer to maybe 75 yards" thing. I hate wounded game. As a result I want to know when I break the trigger that the ball is going to go where pointed if I do my part. Shooting a marginally accurate gun at game is not ethical. But then my "marginal" might be someone else's "great".
Survival weapons etc. The smoothbore loses here unless you can live on ducks and geese. Takes too much powder and lead and lacks pinpoint accuracy for small game. Rifled bore is better. Frankly this is one use where I see the shotgun as borderline useless.
People here have indicated that they have references to late smooth rifles. But where are the surviving examples of say 1840s smooth rifles? I have never seen one that I recall. So far as smooth rifles/buck and ball guns etc. There is simply no way to know if a gun was originally made rifled or smooth. A smooth rifle could have been rifled at later date ala Cline or bored smooth for some reason at some later date.
This is why I keep pointing to economics. From the stand point of cost per shot and game killed the smoothbore will not match the rifle for an average. Are there other factors? People with no shooting skills etc etc sure. But this will not change the economics for the man that CAN shoot. I guess one could say that a pig farmer who cannot shoot worth a darn is better off with a shotgun of some sort. Good chance he can't hunt either and uses his gun to kill beef in the fall (they stuck pigs) Since he hardly ever shoots it ammo cost is not important. Someone who can shoot and knows how to hunt is better off with a rifle unless he eats a lot of waterfowl.
I have hunted since I was old enough to cock a BB gun. I have hunted a lot of different climates and terrain in several states. Other than for a few specific uses (birds or skunks in the henhouse) the rifle is superior to a shotgun anytime that a solid shot is used it makes no sense at all to use a smoothbore unless one simply wants the handicap.
Dan