Today, I want to talk about a cartridge most people have never heard of, the 41 Colt Automatic. Technically, we're going to look at 3 cartridges, including the 9.8mm Colt and the 9.65mm Browning, which you have probably also never heard of, but I'll explain as we go. The .41, arguably a godfather to the 1980s 10mm, was likewise intended to be an improvement upon current service cartridges, yet still in a relatively intermediate caliber. We're going to take an in-depth look at where the cartridges came from and why they never made it to full-scale production. So, let's explore once more into the dawn of the cartridge era. And remember: if you think I'm wrong, fight me in the comments; if you can prove I'm wrong, shoot me an email, I'd love to hear from you.

The.41 caliber was rare throughout the black powder era and didn't see any significant use until 1825, when Philadelphia gunsmith Henry Deringer began producing extremely small cap-and-ball pistols. In fact, his designs were so popular and widely copied that the name Derringer, a misspelling used to avoid trademark lawsuits by his competitors, became synonymous with the tiny designs. The Philadelphia Deringer was available in .31-.50 caliber, but .41 was by far the most common.

While Smith & Wesson maintained a stranglehold on breach-loading revolvers, in 1860, an inventor named Daniel Moore designed a .38 caliber single-shot derringer for rimfire cartridges. By 1865, the patent was sold to the National Arms Company, who began producing the derringer along with a .41 caliber rimfire cartridge, having a case approximately .468" in length and, firing a .401"-.406" 130gr heeled bullet at an average velocity of 520fps. In 1870 National Arms was acquired by Colt, who continued production of the derringer. The next year, in 1871, Colt released two pocket revolvers chambering the .41 rimfire, one 5-shot and one 4-shot, called the House and Colverleaf models respectively. By 1873 Colt released their New Line revolver model as well as a longer 41 rimfire cartridge and a matching 41 centerfire cartridge, called the 41 Colt, with a case length of about .635" and increased bullet weight of 160gr. The 41 Colt was also chambered in the 1873 Single Action Army. 

In 1877, with the release of Colt's first double action revolvers, designed by William Mason, the 41 Colt case was lengthened to .935", creating the 41 Long Colt, firing a 200gr bullet. Coincidently, in the same year the 38-40 rifle cartridge was also offered in the Single action Army.

To make matters entirely confusing, cartridges intended for the double action revolver had a slightly smaller rim diameter, resulting in a Double Action version of both short and long cartridges until the larger rim was discontinued around 1888. Also, because 41 Short could be chambered in 41 Long revolvers, manufacturers producing the short cartridge did so with varying case lengths. 

It wasn't until 1889, when Colt developed a swing-out-cylinder double-action revolver for the U.S. Military, that they finally updated the 41 cartridge to use inside lubricated bullets. However, this change appears to only have been applied to the 41 Long Colt, with all shorter cartridges maintaining use of heeled bullets throughout production. While Army and Navy revolvers were chambered in 38 Colt, commercial pistols were also available in 41 Long Colt. Case length was increased to cover the lube grooves, but the diameter remained the same with bullets reduced to .386". Rather than reduce barrels to match the smaller bullet diameter as they had done with most other cartridges by this time, Colt simply used 38-40 barrels, which had a groove diameter of .400", and hollow-based bullets. This earned the 41 Long Colt a reputation of inaccuracy compared to contemporary cartridges, and remained until it was discontinued around 1940.

Between 1894 and 1900 Colt purchased 4 automatic pistol designs from John Browning and brought one to production with the hope of U.S. Military adoption. By 1902, with the pistols going into field trials, things looked promising, but it was clear that the U.S. was not ready to commit to the pistol. As this was unfolding, Colt began looking abroad. Sales did relatively well in Central and South America, but in continental Europe most countries preferred designs produced domestically. England, unlike almost any other country at the time, also had a caliber requirement, specifying that no pistol submitted for trials should be less than .41 caliber. To meet this requirement Colt began developing a new automatic cartridge based on the 41 Colt for use in the Browning pistol. It is rumored the program may have begun as early as 1901 with input from John Browning, however, there are no surviving records to indicate that Browning had any direct involvement with the 41 Auto program. The earliest known record of the cartridge comes from the logs of the Union Metallic Cartridge Company, dated March 1903. The entry records that cartridge samples had the same case and overall length as the 38 ACP, with a rim diameter of .417"-.422", fired a .386" 150gr jacketed bullet with 6.5gr of Walsrode Shot Gun powder. Velocity is not specified, but is estimated to have been between 1000-1100fps. 

Accounts from Colt are scarce but indicate that the pistol in 41 Auto experienced issues with premature failure of the sear and barrel link pins. While the U.S. Military was reporting similar issues, albeit to a much lesser degree, of 38 ACP pistols in field trials, it was made clear in late 1903, by the Ordnance Department, that the future of U.S. Military handguns was .45 caliber. And just like that, with less than a year of documented development, Colt's 41 Automatic was filed away as another project with no budget and no market prospect.

While Colt and Browning refined the 45 caliber pistol between 1904 and 1910, Colt's 38 ACP pistols continued to see some commercial success, but the 1905 was a relative failure. With the 45 design nearing completion in 1909, the Colt tool room made at least one 38 ACP prototype with the apparent intention of updating the 1900-series 38 ACP pistol line. The prototype used the same frame as the 45 prototype, now known as the Model 1910. The grip of the frame was shortened and the rails were cut down to fit a thinner 4.5" long slide. The project stalled in early 1910, when trials of the 45 prototype revealed issues with the frame and barrel cracking. The same 45 caliber "1910" prototype design was also sold by John Browning to FN. FN would initially begin development of a nearly identical 45 caliber pistol under the title of Grand Browning. 

At the same time, Colt was also in an ongoing territorial dispute with FN. Contracts between Browning, Colt, and FN had divided the markets in which they could sell products which had been designed by Browning. Colt felt that sales by FN to South America and the Caribbean violated this agreement, but their protests received little response. When FN continued sales to Central and South America, Colt, rather than seek litigation, took a more aggressive approach. In late 1909 or very early 1910 they dusted off the 41 Auto, chambered it in the 38 prototype, and gave it a new name: 9.8mm Automatic. Development between UMC, Colt, and Winchester would make the case rimless, .406" in diameter. This would have made it possible to use a single magazine for both cartridges as Browning had done with the FN 1910. A reduced bullet weight of 130gr would increase velocity to approximately 1200fps. By late 1910 the issues with barrel and frame failure had been resolved, a manual safety was added, and additional prototypes were made for upcoming pistol trials in the Balkans. A total of 5 38/9.8 prototypes are known to have been produced. 

In late 1911 Colt representatives presented the pistol and 9.8mm cartridge in Romania, Bulgaria, and Serbia. It is unknown if accounts of the pistol trials survive, but according to Colt's representatives, the cartridge, in particular, was received favorably. Trials continued into 1912, but did not develop any contracts. It did, however, pressure FN back into market negotiations, with Colt agreeing to stay out of continental Europe, and FN from Central America and the Caribbean. This presented some complications, as seen when Norway wanted to adopt the Colt .45. After purchasing rights and designs from Colt, they then had to negotiate with FN before beginning domestic production. In 1913, Colt approved production of the 38/9.8 pistol for the North American market. The smaller frame and slide would likely have sold well commercially. However, Colt had not set up production before war broke out in Europe. With no market open to the 9.8mm cartridge and demand for the 1911 outpacing production, Colt officially abandoned the 38 pistol and 9.8mm cartridge in 1914.

Back in 1910, the President of FN had authorized 30 .45 caliber Grand Browning pistols to be produced. It is unknown how many were actually made, as none are known to have survived. By mid 1912, FN sought to fill the market potential highlighted by Colt's 9.8mm. They developed a nearly identical cartridge called the 9.65mm Browning, following the European tradition of naming cartridges after the bore diameter, the only difference being the use of a somewhat truncated 115gr bullet, with a velocity around 1300fps. This cartridge was chambered in the Grand Browning, and the size of the pistol was reduced slightly to suit it, being generally described as 7/8ths that of the Colt .45, and slightly larger than Colt's 9.8mm pistol.

Production of the 9.65mm Grand Browning is something of an enigma. At this time FN had a policy of not setting up production until a substantially large contract was secured to cover the initial costs. Despite no surviving records of any contract for the Grand Browning, a visitor to the factory in June 1914 later noted that it was "ready for mass production". Whether this means that tooling for production was already in place, or simply that the design had been finalized may never be known. It does give some merit to rumors about Belgian miliary interest in the pistol and cartridge. However, only around 24 Grand Browning pistols are known to exist, and it is uncertain if these are sales models or production samples. The highest serial number recorded is 127, although the absence of lower serial numbers is commonly explained by the speculation that these are sales models and began numbering at 100. By August 1914, the German Army occupied the FN factory. Most of the tooling was carried off during the war, and the majority of company documents were discarded or lost. The factory would primarily be used as a vehicle repair depot and Red Cross hospital until the war's end. 

By the time FN began to reestablish it's production capacity in late 1918 two factors had conspired to prevent any further development of the Grand Browning or the 9.65mm cartridge. The first was that surplus Colt Model 1911s made any chance of selling a similar FN produced pistol entirely unlikely. The second was tens-of-millions of stockpiled 32acp cartridges throughout Europe. When FN did not restart production of the Model 1900, the Army simply adopted the Model 1910, which FN was ready and willing to produce. With no market for the Grand Browning, and nothing to chamber the 9.65mm in, FN, like Colt, abandoned both the pistol and the cartridge.

So there's the history of an automatic cartridge that was almost chambered in the Colt 1900, almost produced by FN, and almost created a smaller version of the 1911. We can only wonder at the potential impact the cartridge may have had. Would it have captured the U.S. police market like the 40 S&W and stifled the legendary .357? Would it have succumbed to the 9mm or held its own across Europe? If the FBI hadn't needed to reinvent the wheel, could we have seen the 10mm during the magnum craze of the 1930s? Everything old, is new again.