Mexican subguns: a quick look

Some days ago, while taking a look at some boxes of “unconventionally-filed” (messed, really) material in search of something, I came across a small brochure surviving from items collected at the 2013 LAAD Defence and Security Show in Rio de Janeiro describing a family of Mexican-made submachine guns being promoted by a company called X-Arms. Since the subject appears to be little known by the general public and a search in TFB-covered subjects was fruitless, I decided to give it some light.

The whole story started in the early 1930s, when Rafael Mendoza of Mexico’s Fábrica Nacional de Armas developed a gas-operated light machine gun which was subsequently adopted by the local Army as the Model C-1934 in 7x57mm, but became generally known as the “Mendoza” (Ian has described it in https://www.forgottenweapons.com/light-machine-guns/mexican-mendoza-lmg/). The designer later (the 1950s) established his own Productos Mendoza S.A. company in Mexico City, from which a few submachine gun designs emerged and, reportedly, were built in very limited numbers for the Mexican Army. Available in 9x19mm, .45 ACP, and .38 Super calibers with cyclic rate of fires of around 650 rounds per minute, the weapons looked more like beefed-up pistols/machine pistols (recoil spring around the barrel) with a tubular stock attached to the rear of the pistol grip. Belt-worn leather holsters were available for them.

On June 30, 1975, Hector Mendoza Orozco, Rafael’s son, filed a U.S. patent request for a “portable submachine gun”, which was granted (Number 3987571) on October 26, 1976. This was then initially promoted for sales as the Modelo HM-3 from the original Productos Mendoza S.A. concern, still headquartered in the Mexican capital city. Overall, it was pretty much his dad’s RM-3, including the fixed tubular stock, which the designer claimed was “always ready to use, without any delay in moving to the firing position”. Basic specifications of the selective fire (about 600 rpm, cyclic) weapon: Barrel length, 255mm; overall length, 635mm; loaded (32-rd magazine) weight, 3.35kg.

The next evolutionary step was the HM-3-S, which adopted a wire-type stock that folded upwards and onto the top of the gun, while the cocking serrations on the bolt gave place to a large bolted-on aluminum cocking piece, U-shaped in the center so as not to interfere with the sights use. A short, synthetic handguard was introduced, the gun finding service with Mexican police forces.

A two-part video showing the (somewhat complicated) stripping of an HM-3-S: https://www.youtube.com/watch?v=XO1VeNgXujU and https://www.youtube.com/watch?v=F2O4iqv_zYM .

By the end of 2009, Productos Mendoza S.A. had developed .380 ACP versions of the sub guns, called Cobra 380 and Bulldog 380, with some local marketing efforts taking place from 2011 on. An international sales campaign was underway in 2013 when the so-called X-Arms Tactical Weapon System was displayed at Rio de Janeiro’s 2013 LAAD Defence and Security Show (remember my opening paragraph?). The weapons received good attention from the exhibition visitors, mainly due to the fact of being from a generally-unknown manufacturer. This interest was to the point that two cased guns were eventually stolen (!) from the manufacturer’s booth, but the thieves were luckily spotted and arrested by local security before exiting the showgrounds.