Matchlocks to Assault Rifles: Part 6, The Percussion-lock Minie Bullet Muzzle-loading Rifle (Page 2)

This is page two of a two-page article. Page one can be found here.

The other main weakness of the older muzzle-loading rifles, and indeed the muzzle-loading smoothbore muskets too, was the unreliable firing mechanism – the flintlock. The flintlock required a tiny amount of gunpowder to be placed in the pan alongside the breech end of the barrel, where it was ignited by sparks from the flint which then passed through a touch-hole bored in the barrel to ignite the main gunpowder charge inside the barrel. Although the pan had a lid, it was still vulnerable to wind and damp and to misfires if the flint wasn’t adjusted to strike the steel cleanly and generate lots of sparks.

This was solved by the percussion lock and percussion cap.

The cap was a small metal cylinder or can a few millimetres across, open at one end and containing fulminate of mercury, a chemical which ignited and sparked when hit hard. Those of you who used a children’s cap gun as a kid might remember the individual plastic caps that made a bang – just think of the same thing in copper instead of plastic and with a more powerful bang!

The pan of the flintlock was replaced by a nipple (don’t snigger) projecting from the gun onto which the cap was placed. The arm holding the flint of a flintlock was replaced by a simple hammer arm. On pulling the trigger, the hammer came down on the cap, igniting the tiny amount of chemical inside it, sending a flash down the hole in the middle of the nipple to ignite the main charge in the barrel.

This percussion lock system was a lot more reliable than the flintlock and slightly quicker to prepare for firing too. Old flintlocks could even be converted to the new system fairly easily, just by removing and replacing the lock mechanism, making it economic to switch.

The percussion lock was developed around 1830 but not adopted immediately. The British Army tested a percussion lock musket in 1834 but only adopted it in the late 1830s and didn’t really make it the majority weapon until 1841. There was, therefore, a brief period when muzzle-loading smoothbore percussion lock muskets were the main infantry arm (before being replaced with muzzle-loading percussion lock rifles using Minie bullets) and I should really include this as a milestone stage in its own right, but the period these were in use was quite short.

So by the mid 1850s the main infantry weapon of a well-equipped army was the muzzle-loading percussion lock rifle firing Minie bullets. Note, though, that the bullet and main charge of gunpowder still came in paper cartridges and had to be loaded and rammed down in the same way as the flintlock muskets. The metal cartridge that could be loaded as a single item wasn’t yet around.

The muzzle-loading rifle with percussion lock and firing Minie bullets, was the main firearm of the infantry in the American Civil War (though older percussion lock smoothbores and even flintlocks were in use at the start as the states scrambled for weapons to equip the new regiments they were raising). It had an effective range of 300 yards (though a marksman could hit a man out to 500 yards) and a rate of fire of about four shots per minute, making frontal attacks more and more costly. But they were still not costly enough to preclude them completely since the end result of a successful rush – completely sweeping the enemy away – was a valuable outcome. What it meant instead was that commanders started to realise the necessity of softening the enemy up with an extended firefight before launching a charge, or adopting fire and manoeuvre tactics where one group of men laid down covering fire whilst another group advanced.

The next advance would be the adoption of breech-loading rifles, where the gun was loaded from the breech end of the barrel, the end nearest the firer, and I’ll cover that in part seven of this series.