Well, there's often some confusion when it comes to these terms, especially rifled musket and rifle musket which are two different weapons.
"Musket" of course describes a long barreled smoothbore muzzleloading weapon either flint or percussion. It fires a round ball. The barrel length is generally 39 inches or longer, usually no more than 45 inches. Remember though that during the Revolution and earlier a carbine had a barrel as long as 42 inches. That's a whole new topic. And of course there were the civilian "muskets" which basically were fowling pieces that followed a military "pattern". And some of these were adapted to take a bayonet. The MinuteMan was always ready to hunt or go to war.
A "rifled musket" is an originally smoothbored musket that has been rifled at a later date to use the elongated expanding ball, otherwise known as the Minie. (In Europe the Thouvenin System was also used which is a different way of expanding a round ball). Usually, when rifled, the musket was also altered to percussion, although the US did rifle a few flintlock M1835 muskets as an experiment. Thousands of M1816, M1835 flint muskets were rifled and percussioned in the 1840's and 50's. Quite a few percussion smoothbore M1842's were also rifled.
In 1855 the US adopted an all new percussion "rifle-musket". This is a weapon that was designed from the ground up as a rifle of musket length and caliber. The caliber was smaller than the old smoothbores (.58 vs. .69). The barrels on these guns were 2 inches shorter (40 inches) than the smoothbores. Now the Europeans were doing the same thing at the time, in fact were a little ahead of the US. The British smoothbores gave way to the P51's and finally the P53's which were similiar in caliber and barrel length (.577 and 39 inches). France, Belgium and the German States were all following in a similiar fashion, though most of their altered muskets were of even bigger calibers. And all experimented with different percussion ignition systems though the standard percussion system was the norm. The US, on the M1855 used the Maynard tape primer. This lock would also accept the common musket cap and on the M1861 they did away with the Maynard system.
The military "rifle" at least in the US, was basically a rifle-musket with a shorter barrel. In the US, the standard was 33 inches. And instead of an angular socket bayonet, used a yataghan style or as most people call it, a sword bayonet. This gave the soldier pretty much the same reach with his weapon as the soldier with the musket and socket bayonet. And of course the sword bayonet could double as a short sword.
With the end of the muzzleloading era, the term musket pretty much disappeared as a description of the weapon though the term remained in manuals for years describing the use of long arms. (I read somewhere about a soldier long after this period being condemned for some crime. He was to be "shot to death by musketry". I believe it was someone in the British Army).
There are a few exceptions though. Both Sharps and Spencer made and sold to the US Ordnance Dept. breechloading "muskets". These were 3 band breechloading and repeating rifles but were designated as "muskets".
We used to have "musket matches" at our club (I'd like to get started again soon), and these were for rifle or rifled-muskets, though if someone wanted to, they could use a smoothbore (which rarely happened). Any length barrel was legal, which meant that carbines and musketoons could be used as long as they were muzzleloading. The only requirement was that the minimum caliber was .54. If you look at the history of military shoulder arms, especially in this country, you'll find that .54 was the minimum for muzzleloading guns that were adopted by the US Army and put into production.
And after the Allin conversion was adopted and the caliber was reduced to .50 and then .45 you have true "rifles".
I hope nobody fell asleep before they got to the end of this epistle!
:yakyak: