Your cart is currently empty!
The history and development of the 38 ACP begins with John Browning’s first pistol designs and the 38 S&W cartridge. Between 1894 and 1896 Browning developed four pistols utilizing four different operating principles; gas operated, blowback, short-recoil dropping barrel, and short-recoil rotating barrel. It is unclear if these first prototypes fired typical 38 S&W cartridges or if Browning began modifying the cartridge while developing the pistols. In either case, in 1896 Colt acquired patent rights to produce Browning’s pistols in the US. Continued cartridge development would primarily be overseen by Colt, for use in Browning’s dropping barrel pistol, with production done at UMC and Winchester.
The earliest surviving cartridges, from 1897, are experimental samples from Winchester. The case is rimless and bullets are slightly lighter weight and smaller diameter than typical 38 S&W.
By 1898 the case was lengthened and featured a semi-rim. This case configuration would become standard throughout production.
In 1899 the Army Ordnance Board began testing the new Colt/Browning pistol and cartridge. The cartridge was given the nominal dimension of 9x23mm SR, and fired a 105gr jacketed round nosed bullet at just over 1300fps. Testing was intermittent due to a shortage of ammunition, with full scale cartridge production not starting until mid 1900.
During the Thompson-LaGarde tests in 1904 two 38 ACP cartridges were used. One fired a jacketed soft-point 120gr bullet at 1048fps, and the other a full metal jacket 130gr bullet with a velocity of 1107fps.
Development of a 38 automatic cartridge for use by the military was abandoned in 1904 when the Ordnance Board required that any new pistol be no less than .45 caliber. From this point records of the 38 ACP’s development are scarce, as few commercial records survive. Available records and catalogs suggest that no significant developments were made with the cartridge between 1906 and the early 1930s.
In 1920 SAMSAA, a precursor to SAAMI, published dimensions, officially labeling the cartridge 38 Automatic. In 1926 SAAMI was established and immediately began consolidating and standardizing cartridge variations. During this time the wide range of bullet weights available for 38 ACP was consolidated and the 130gr bullet became standard across all manufactures. Pressures still varied, however, with velocities ranging from 1080fps to 1190fps.
In 1928 Colt released the m1911 pistol chambered for 38 ACP with the model name “Super 38 Automatic”. It is a common misconception that a new cartridge was also released with the pistol, but ads, articles, and catalogs from 1928-1930 confirm the use of standard 38 ACP. It was not until about 1933 that a high velocity loading of the 38 ACP was introduced specifically for Colt’s Super 38 Automatic pistol. The new load pushed the standard 130gr bullet at 1300fps.
The high velocity loads bore the same headstamp as typical 38 ACP and were only distinguished by packaging labels. Very quickly most manufactures began using nickel plated cases, likely to aid in extraction of the higher pressure cartridge, and this was the only visual distinction between standard and high velocity loads until the 1970s.
The name “38 Super” appears as early as 1929 with authors applying the misnomer to both the pistol and the cartridge. Naming conventions were inconsistent between manufactures and distributors but eventually the title “38 Super” stuck and became the standard designation for the high velocity loading.
In 1974 SAAMI began to standardize high pressure variations of cartridges and added a “+P” designation to denote this standard. In 1979 SAAMI published pressure standards for the 38 ACP; 38 Automatic with a maximum pressure of 23,000cup (26,500psi) and its high pressure variant titled 38 Super Automatic +P with a maximum pressure of 33,000cup (36,500psi). When manufactures applied these standards to the cartridges standard velocity using a 130gr bullet became 1040fps and 1280fps respectively. While these new standards were a step backwards in cartridge performance they did provide a margin of safety when shooting old Colt pistols, for both the shooter and the gun.
During the 1970s the rise of competitive sport shooting caused a revival of the 38 ACP/38 Super. By the 1980s developments in 1911 barrel design allowed handloaders to push the cartridge to its extreme limitations, prompting manufactures to design stronger, thicker cases. In the 1990s the use of doublestack magazines in the 1911 spurred the development of new versions of the 38 cartridge, such as the 38 Super Comp, which featured smaller rim diameters and enlarged extractor grooves. Combining case developments with advances in bullet design, the mid 2000s-2010s saw what will probably be the widest selection of ammunition based on the 38 ACP. Despite a subsequent waning in popularity and availability the cartridge and its variations look to remain on the market for many years to come.