INA Model 953

Lore & Background

The INA Model 953 was produced under license from Madsen, with manufacturing beginning in 1950. The first model, marked M.B.-50, was produced until 1953 and featured a large Brazilian crest. In late 1953, the Model 1953 was introduced with several improvements: a larger magazine housing, a metal loop riveted to the lower right side of the magazine housing to hold it together, and the retracting handle moved from the top to the right side. The buffer spring, extractor, ejector, and firing pin were also changed.

The firearm is constructed from stamped sheet metal in an open-bolt design, firing from a locked-back bolt with a fixed firing pin. The receiver is made from two pieces of sheet metal shaped with an integral rear pistol grip and magazine housing, fitting together like a clamshell with a hinge at the rear of the pistol grip. The two halves split down the middle of the top and bottom of the receiver and are held together by a barrel locking nut threaded onto the fore section. The folding stock is made of tubular steel and folds to the right side.

The Model 953 fires only in full auto and has a unique safety lever located in front of the forward magazine housing. Firing requires gripping the magazine housing and holding down the safety lever.

Reader's Guide

The INA Model 953 holds a distinct place in small arms history due to its association with urban guerrilla warfare in Brazil. Its recommendation by Carlos Marighella in his 'Minimanual of the Urban Guerrilla' as the ideal submachine gun for such operations gave it a symbolic and practical significance beyond its military use. The design, based on the Madsen M/50, was adapted with specific features such as the forward safety lever and clamshell receiver construction. The weapon was used by the Brazilian military and also by non-state actors including the Brazilian Communist Party, Ação Libertadora Nacional, and Vanguarda Armada Revolucionaria Palmares. Its stamped sheet metal construction and simple open-bolt mechanism made it relatively inexpensive and easy to produce, while the full-auto-only capability and unique safety arrangement reflected its intended role in close-quarters combat. The Model 953 remains a notable example of a licensed design adapted for local production and specific tactical doctrine.

Did You Know?

• The receiver is made of two stamped sheet metal halves that split down the middle and are held together by a barrel locking nut.
• The Model 953 has a safety lever in front of the magazine housing that must be held down to fire.
• It was used by the Brazilian military and by groups such as the Brazilian Communist Party and Ação Libertadora Nacional.