Hi there, historians of Reddit!
The first time this question occurred to me was back when I visited the Little Bighorn battlefield when I was still in high school (i.e. a long time ago). In the museum, it was mentioned that many of the Lakota warriors were actually better armed than the U.S. cavalry at the time, with the latter still using single-shot carbines while the former had repeaters bought from European/American traders. This fact proved to be a shock to me, since it essentially destroyed my assumption that indigenous forces were always far behind colonial powers in terms of military might/technology.
Anyways, my interest in the subject came back recently after I did a bit of reading on the latter half of the American Civil War, specifically General Sherman's Georgia campaign. I'm aware the majority of infantry were armed with rifled-muskets, but in my research I came across some references to soldiers/companies in the Sherman's forces being armed with Henry Repeating Rifles. There was even a photograph of six or seven soldiers posing with them as well, with a quote from a Confederate soldiers complaining about having fight repeater-armed Union troops or something along those lines.
My knowledge on the American army during the Reconstruction era is hazy at best, but since the U.S infantry largely used five-shot (Springfield?) bolt actions during the Spanish American war, I'm assuming the army never formally adopted repeaters into it's arsenal.
So, why exactly didn't they? I mean, in Europe the Prussian Dreyse/Needle rifle and the French Chassepote revolutionized infantry tactics on the continent, and both of those rifles had a far slower rate of fire (not to mention ammo capacity) than any of their repeating contemporaries. Was it the price of the guns that prevented the army from purchasing them in large quantities, or was it something else?
Thanks to anyone who responds, and thanks for being awesome!
- 4th year History major
With most major powers, repeaters ran into problems with logistics and institutional inertia that kept them from seeing widespread adoption as infantry rifles.
In the era of the Rifled Musket (as the Civil War was), repeaters like the Henry ran into a myriad of major problems relating to logistics that made them unsuitable for widespread adoption even if the American military establishment wasn't as extremely conservative as it was at the time. Repeaters were significantly more complicated and expensive to produce than the rifled muskets in then in use, and their brass-cased ammunition, while incredibly modern, required significantly more complicated manufacturing facilities to produce than the free-floating black powder and percussion caps used for rifled muskets. Repeating arms available during the Civil War also ran into issues with production, as they were private ventures made by companies that lacked the manufacturing base to keep up with the demand for the entire Union Army, and tooling up existing arsenals for the new weapons in wartime was going to be costly and time consuming while cutting into existing rifle supply at a time when the were high in demand. Most of the repeaters available in the Civil War also had their drawbacks that tended to vary based on the design. The Henry, for example, had an incredibly anemic cartridge even by standards of the time. While infantry rifles of the time had sights reaching out to 500 yards for long-range volley fire, the Henry's weak cartridge lost a lot of energy and effectiveness outside of 100 yards. The Colt Revolving Rifle, which made a major impact at the Battle of Chickamauga, shared a lot of the issues of other cap-and-ball revolvers - loading the cylinder was even more time consuming than loading a single-shot rifled musket, and the gap between cylinder and barrel made it a major safety hazard for the shooter.
Despite all of that, some of these concerns - particularly those relating to the use of cartridges - fall apart shortly after the Civil War once the US Army adopts a cartridge-firing breech-loader (the Trapdoor Springfield) and much of the rest of the world does the same. You've noted, as have many others, however, that the Army (and many foreign powers) continued to use single-shot rifles well beyond the time when magazine-fed rifles were widely available. The problem here becomes twofold - logistics and sustained fire rates. Logistics is more easy to understand. For pre-industrial armies that expected to have to do long campaigns far from railheads, conserving ammunition was a major concern. Chickamauga saw the Union's repeater-armed unit run out of ammunition at times despite their success in fending off attacking forces, for example. Post-Civil-War, supply of ammunition became an even more pressing concern, as American forces were often operating in remote frontier areas far from railheads or any possibility of local supply, so everything they needed had to be carried along with them. The high (short-term) volume of fire afforded by a magazine rifle may be tactically significant, but strategically it would become a liability. On that note, magazine rifles - up until the invention of the charger and en-bloc clips that allowed for rapid loading of multiple rounds at a time - ran into the problem of reloading. While they had a higher rate of fire than a single-shot rifle while they fired from magazine, all else being equal, once the magazine rifle had to reload, they suffer from an extended reloading period that means they're not any faster-firing in the long-term than a single-shot rifle.
We'd see both of these concerns recognized and accounted for even as nations slowly began to adopt magazine rifles. Units that were equipped with magazine rifles tended to be cavalry, as their greater mobility meant logistical concerns were less of an issue. Later on, navies often drove the procurement of magazine rifles, the logic generally following the line of thought that logistics was less of an issue when the ships themselves could carry vast quantities of ammunition, and the high short-term volume of fire the guns could put out was important for fending off boarding parties and torpedo boats.
When armies finally did adopt magazine rifles for the standard infantryman, we'd see a lot of previous concerns shine through in their designs. The most obvious of these was the magazine cutoff, which allowed the user to disengage the magazine and fire as a single shot, generally until the commanding officer ordered magazine fire. The intention was to keep magazines in reserves for emergencies and avoid having soldiers fire off all of their ammunition in an un-aimed panic by forcing them to single-load. This thinking wasn't exclusive to the US - both the French Lebel 1886 and British Lee-Enfield had magazine cutoffs. The Boer and Spanish-American Wars would cause a re-evaluation of rifle designs for their respective victors (the British updating the Lee-Enfield for charger-clip loading and the Americans developing the Springfield 1903 to replace the Krag-Jorgensen), but the underlying logistical concerns that drove rifle development to that point didn't really go away until WW1 showed that supply in industrialized warfare wasn't going to be as difficult as expected.