Cartridges of the Mondragon Rifle
These are the cartridges that were used in the manual bolt action and the self loading rifles. The 30-30 was only used in a single Model 1900 presentation rifle that was given to President Porfirio Diaz.
This rifle, in 30-30 Winchester, resides in the Museo del Ejercito Mexicano, according to Mr Tanner, “Guns of the World” page 295.
(I’d love to get some color photos of that one!)
5.2 x 68mm Mondragon
Since the rifle was being built by SIG, a Swiss arms company, it would make logical sense that Mondragon would seek out the famous Colonel Rubin, the famous Swiss cartridge inventor, to design a cartridge specifically for the Mondragon rifle. Colonel Rubin invented the 7.5 Swiss and British .303 to name a couple.
This new 5.2 mm round was very high tech with super performance for a cartridge of the late 1800’s. Utilizing a rimless case the bullet speed would be double that of black powder cartridges, 2900 fps vs 1400 fps. This cartridge was the 5.2mm series and was tested in several different calibers, lengths and loadings. Mondragon eventually settled on the 5.2 x 68mm for the manual breech loading bolt action guns. I have limited information about this round because I can only draw conclusions based on my personal collection of only 3 rounds and whatever info I can find in books. If you are interested in this cartridge look up “GUNS OF THE WORLD”, 1972, and the “MONDRAGON” article on page 286, by Mr Hans Tanner
The center bullet is a 5.5 x 68mm (.218″ caliber) it is flanked by two of the generally adopted 5.2 x 68mm (.208″ caliber) rounds. The case length for both rounds is 68mm, but the overall length of the 5.5mm cartridge is longer (I’m guessing it has the 105 gr bullet). The length of the 5.5 x 68mm cartridge is 79.6mm vs 77.2mm for the 5.2 x 68mm. The longer cartridge also has a sharper shoulder. I weighed the two for a comparison and the longer 5.5 cartridge is 357.4 gr vs 350.0 gr.
What appears to be a very small bullet, of .208 caliber, is actually a 90 grain projectile that is 1.2 inches long and seated very deeply into the case. Whether the washer and bullet combination is just is for support because of the small neck surface area, or is there a “Colonel Rubin” secret? Does this “expanding chamber” reduce the chamber pressure during combustion and the gas expansion phase of firing? Perhaps someone with a better understanding of chamber combustion pressures will fill us in.
The projectile is 90-grain jacketed bullet of .208 caliber and was launched at 2900 fps. That doesn’t sound like much compared to cartridges of today, but consider this, the current 5.56 NATO round fires a 62 grain bullet of .223 at about 3000 fps.
A flatter shooting cartridge requires less ballistic guesswork on the part of the soldier.
Manufacturing and loading of this cartridge must have been tricky. As an avid reloader, I tried to go through the sequence of making one of these rounds. The only way I can see to make this round is to start with a straight wall case, looking something like a rimless 45-70, next add a primer to prevent the powder from falling out of the bottom, crimp the case to prevent the bullet and ring from sliding to the bottom of the case, add the powder, mate the bullet/washer combination, position the bullet/washer on the case crimp and lastly form the neck and shoulder around the loaded cartridge.
It would appear that this 5.2 x 68 brass case could only be used once, probably another reason why it was not adopted.
The advent of smokeless powders in the late 1800’s initiated a radical series of new cartridges of smaller calibers. With Mondragon’s radical new gun design, a new cartridge was also needed. General Mondragon must have been so impressed by the new European small calibers such as the 6.5 x 55mm Swedish and the 6.5 x 54mm Mannlicher cartridges that he created his own. Mondragon’s first cartridge which was similar to the European versions was called the 6.5 x 53mm Mondragon.
(It’s his gun, why can’t he call it that?)
The first bolt action Mondragon rifles used a 6, 8 or 10 round, double stack en-bloc, clip for his 1890 and Model 1900 rifles. (depending on the caliber)
(I’ll bet you thought Mr Garand invented it! Remember this is 1893!)
(I don’t have an actual 6.5 Mondragon to measure, the one above was made at a machine shop for display and comparison purposes. I have never seen a real one….. very, very hard to find.)
7x57mm Mauser, 7.65 Argentine and the 7.5x55mm Swiss
The first two rounds were specifically chosen for the South American market, these calibers were already popular south of the US border. The 7.5 x 55mm Swiss round was a conversion for some trials guns tested by the Swiss forces designated the Model 1917.
You will find 99% of the Mondragon self-loading rifles in 7x57mm Mauser.
I have found two types of EN-BLOC clips used in the early Mondragon rifles, a small and a large. There may be more that I haven’t come across yet.
The small clip version on the left is an original Mondragon clip. The clip on the right and in the gun on the right is a modified Garand clip. Yes! you heard right….a MODIFIED Garand clip. Only a few thousandths of an inch seem to separate them, probably just enough to keep the lawyers away from any patent infringement.
(The Mondragon version was first!)
The Model 1908 uses the standard 5 round Mauser stripper clips as found in the German rifles of the Great War and later.
Right is 7mm Mauser stripper clip.
Bottom left is 8mm Mauser stripper clip.
The stripper clips keep the rounds together for transport and feeding the magazine, the rounds are pushed into the magazine and the clip is then discarded.