Rifles of the Gran Chaco War

   by Dan Reynolds
The Chaco Boreal or Gran Chaco region of South America is a vast inland area of scrub land about the size of Poland.  It is south of the Amazon basin and north of Argentina , bordered on the west by the Andes and on the east by the Rio Paraguay.

Control of this region has been disputed by Paraguay and Bolivia since the end of Spanish colonial rule. The area was considered almost worthless by both nations except for reasons of  prestige.  It was inhabited only by a small number of native tribes which spoke only their native tongue and whom lived a subsistence existence.

This situation changed after the 1879-84 War of the Pacific in which Chile defeated both  Peru and Bolivia, seizing Bolivia's seacoast and only port and outlet to the world.  Bolivia saw the possibility of establishing a port on the Rio Paraguay, which flowed through the Chaco, for an outlet to the Atlantic.  Over the next sixty years the border dispute festered.

As the new century dawned both Bolivia and Paraguay had standardized on the 7.65mm  Argentine Mauser cartridge, as had Peru.  Both had Modelo Argentino 1891 Mausers in issue.  Some or all of these weapons may have been provided by Argentina for geopolitical reasons growing out of rivalries with Chile and Brazil and the inabilities of either or both of these nations to arrange financing of the purchase of new rifles directly from the European manufacturers.  It is unlikely that these would be gifts, but it is possible that some sort of barter arrangement  was made.

Both Bolivia and Paraguay purchased new rifles based on the German Model 98 action in the first decade of the new century.  Bolivia chose the Modelo 1908 from DWM which featured  an unusual upper band assembly.  It was designed to be compatible with the the Model 1891 type of bayonet and had a hook to accept the Gew.98 sling hanger used for shortening and stowing the sling on the rifle when it was not in use.  The stock lacked a pistol grip on the dual short rifle/carbine which could be issued to cavalry or other non-infantry units.  The Paraguayan Army purchased an unknown quantity of the Mauser Modelo 1907 rifle and carbine, and possibly some Modelo 1910 of the Turkish pattern, both in 7.65mm, from Mauser  Oberendorf.  These were the best rifles that Paraguay ever had.

  In the early 1920's the situation again heated up. Both countries were very poor and could ill afford a strong military.  Bolivia had tin and oil resources with which to earn foreign exchange, but Paraguay had strictly an agricultural economy which did not earn any meaningful foreign currency.

Both nations sought to strengthen their military potential.  The Bolivian Army had had a German military training mission since 1911 under Hans von Kundt, major, and later general, and Chief of Staff.  The Ejercito Boliviano was organized along pre war German lines, but was not very efficient due to the quality of the officer corp and the lack of resources to support a modern army.  Standard Oil had the concession to exploit the oil resources which were being developed. Loans to finance arms purchases were obtained from U.S. and Canadian banks, the collateral being revenues based on oil and tin exports.

The contract to rearm the Bolivian forces was given to Vickers, the British armaments conglomerate, probably because of the assistance and influence of British capital.  The new Mauser 7.65mm rifles and 7.65mm ZB26 LMG's were subcontracted from ZB in Brno, Czechoslovakia.  Vickers supplied heavy 7.65mm tripod mounted machine guns, some 7.65mm Vickers Berthier bipod mounted light machine guns,and artillery.

The Bolivian Army was primarily a political instrument which was used to change governments.  Unlike Paraguay where these same types of coups were the way of effecting changes of government, in Bolivia armed conflict rarely ensued.  A meeting was called, regiments and rifles were counted and the loser went into exile with a golden parachute.

Because of this wear and tear on small arms was minimized and loss of rifles by the losing  side melting away with weapons was rare, inventory remained stable over the decades.  In Paraguay, there were 41 presidents in 40 years and armed conflict was the the norm.  In 1924 the Paraguayan Army was down to less than 4000 serviceable rifles as a result of this type of violent action.

The Paraguayan ambassador to the United States was dispatched on a tour of Europe in 1925 to search out affordable modern weapons to build up the strength of the nation in the expected war with the better armed Bolivia, which also greatly out-numbered Paraguay.  As a result of The War of Triple Alliance , Brazil, Argentina, and Uruguay had killed off most of military age Paraguayan males late in the previous century.  This minister toured Europe in search of affordable weapons.  The shortage of rifles was such that many obsolete black powder weapons were in service. Because cost and financing were the most important factors, the decision was made to have the Modelo 1907 Mauser rifle copied and produced at Oviedo Arsenal in Spain.  These decision imperatives had unfortunate consequences on the users of these Modelo1927 Mausers.

The production of these M1927 Mausers got under way in the early part of 1927 and were financed in part by public subscription to a Rifle Fund.  All members of the armed forces and all government workers contributed one months pay tot his effort.  Individuals and companies also contributed.  The total raised was $110,000 U.S. Dollars (1927 Dollars today worth about $2,800,00). Production proceeded slowly and by late summer 1928 some 8700 rifles and 1500 carbines had been procured.

In September an armed clash in the Chaco region between Bolivian and Paraguayan forces in a disputed area, called the Verguardia Incident, lead to war hysteria and the government pressured Oviedo to speed up production.  There were problems with the new rifles.  Reports of rifles blowing up on discharge, and a general disaffection with the quality of manufacture were heard.  Of course, there was nothing to be done.  The quality of the standard, the beautiful German made Modelo 1907, could not be had at a cut-rate price from a Spanish Arsenal using inferior steel.  Meanwhile in Bolivia, the excellent Czech VZ-24 short rifles and ZB-26 LMG's were received with great satisfaction and no reports of trouble.

The winds of war were calmed when outside intervention and mediation led to a compromise resolution of the Incident without war ..."for now".  Chile had staged a military demonstration on Bolivia's border to encourage agreement.  The basic conflict remained and flared into full war in 1932.

An attack by Bolivian troops on a Paraguayan outpost led to this major conflict.  The ensuing struggle was fought under miserable conditions and the troops on both sides suffered greatly.  Conditions in the Chaco were very bad.  The winters were dry and temperatures could drop below zero when storms blew in from the Antarctic.  The provision of enough drinking water was the biggest logistic problem.  Even in the rainy summer season, when the parched sands became a muddy quagmire, a sudden storm from the pole, could drop the temperature from the 80's to below freezing in a few hours.

At the start of the war, Paraguay had on hand a total of 21,450 rifles. These included about 4000 older 7.65mm Mausers including the Modelo Argentino 1891 and 7.65mm Modelo 1907, 10,363 Oviedo made copies of 7.65mm Modelo 1907 rifle called the Modelo 1927, about 1500 Modelo 1927 carbines, and 7,000 Belgian FN Modelo 1924 7.65mm short rifles. [ There are apparent conflicting reports as to a Paraguyan Modelo 1895 Mauser; one source says these were Modelo Argentino 1891 pattern rifles and 15, 000 were acquired circa 1895-1902 while others say that it was a type of the M1895 Chilean pattern.   If indeed it was a Chilean pattern rifle these would be part of the total 21,450 serviceable rifles. ] Both sides used 7.65mm Colt Browning, Maxim and Vickers water cooled machine guns, tripod mounted Madsens, as well as Madsens configured with only bipods for platoon level support. The Bolivians had about 4000 older Mausers dating back to before 1910, and 39097 recently obtained modern Mausers (mostly ZB Vz24) on hand when war broke out along with a good number of the excellent ZB26 light machine gun, the finest in the world for its time.

The outnumbered Paraguayans slowly but surely advanced against material odds until they eventually won control of almost all the Chaco.  They were much better motivated and led. One fact soon became apparent, the Paraguayan troops would discard their M1927 Spanish made Mauser as soon as they could lay hands on a captured VZ-24 or other quality Bolivian Mauser.  At the Second Battle of Nanawa , the Field Commander of the Paraguayan Army was touring the battlefield after the decisive defeat of the Bolivians and saw nearly 3000 of their dead with a Modelo Paraguayano 1927 neatly placed upon each body.  Asking the local commander the meaning of this bizarre sight, he was told that the victorious Paraguayans had taken the good "Vickers rifles", as the Bolivians called the Brno Mausers, and left their Oviedos as a mark of respect for the valor of the dead.

The Paraguayan troops went barefoot and preferred the machete in hand to hand combat.  Many White Russian officers served Paraguay.  The Bolivians lost a very large number of weapons in combat At Campo Via on 11 December 1933: they lost 8000 Mausers, 500 machine guns, and 25 Stokes-Brandt mortars.  This major defeat caused General Hans Kundt his job.

Throughout the war large numbers of rifles were lost to the Paraguayans.   During a truce in December 1933, 45000 additional rifles were acquired including ZB Vz24, Mauser Werke Standard Modell 1933, and FN 1930 type Mausers.

Bolivia was at a bad disadvantage logistically in that all supplies had to be moved from the Bolivian highlands northwest of the Chaco, to the railhead nearest the flat , scrub desert, and then packed or trucked hundreds of kilometers, over poor tracks in the wilderness, to the action.  Despite this the Bolivians had a huge advantage in aircraft and armament as well as motor transport.  By 1935, after a slow, grinding campaign, Bolivia had been pushed out of most of the Chaco and both sides were played out with a combined total of 100,000 dead.

International mediation led to a settlement which gave most of the land to Paraguay. Argentina had provided support to Paraguay during the war, including arms and ammunition. Vast numbers of weapons were acquired during the course of the war.  Bolivia obtained over 100,000 Czech Mausers of various models in the prewar buildup and during 1932-35 and into 1938.  This was the first war in which the submachine gun was widely employed. Details on specific types and quantities of weapons are hard to uncover.


World's Guns, Golden State Arms, 1958

The Chaco War, Bruce Farcau, 1996

Mauser Bolt Rifles, Ludwig Olsen 1976

Rifles of the World, John Walter