OK I have decided to keep with the ECW theme a little and try to post some little bits that most won't know and I have a real shocker that was covered up for Religious harmony. To this day it has been covered up almost exclusively, but that as they say is for another day.
If you talk about rifled barrels you often think of Green Jacketed British Riflemen. If your of the fairer sex it may well be Shaun Bean in his tight britches. Whilst I am not claiming that my example is the first use nor is it likely to be the one most people (read many people) think of but I think it's the most interesting!!!
Prince Rupert received a brace of pistols and was showing them to his Uncle. Being a bit of a show off he took aim at the Metal Cockerel atop of Colchester Cathedral (I think I remember this right) and fired. The bullet hit his mark and his Uncle declared it the most lucky shot and wagered he could not do the same again. Rupert took up his second pistol and again hit his mark. The King was so impressed he not only paid the bet but bought a pair of pistols for himself.
These pistols had a screw on barrel that had to be taken off to load it. The bullet (a lead ball) was larger than the hole at the end of the barrel but at the other end it was wider. The barrel tapered down to the exit and also had groves cut into the barrel that spiralled around the inside of the barrel. The combination of the rifling and the reduced size of the barrel both span the ball and added to the exit speed. This combination meant that the ball would both travel further but also straighter. The draw backs were the cost of a set of these pistols and the time it would take to reload. These were more fashion items that weapons for the battlefield. Still it pre-dated the 37L ATG of the Germans which used exactly the same principle.