MAC-58

By September 23, 1950 the DM 46 ST/MRA Manufacture d'Armes de Châtellerault began to develop a 12.7 mm machine gun to replace the M2 Browning.

Only the caliber of the weapon was specified. Other features were left to the initiative of consulting firms involved in Mulhouse, Châtellerault and Saint Étienne.

In Chatellerault, the study was entrusted to a Davail Technician under the orders of Chief Engineer Martin and the instigation of directors, BMI and BMI Rabbe Nardin. On February 12, 1956, it culminated in a dimensional drawing of the weapon and was submitted to the technical department of the Direction des études et fabrications d'armement (Directorate of Weapons Manufacture and Study), resulting in the creation of a prototype. The weapon was inspired by the AA-52 general purpose machine gun, with steel pressed shells that necessitated the use of 3-400 ton press within the MAC. It weighed 26 kg, that except in the machine guns M2 HB CAL US .50 (39 kg).

Specifications that would meet the 12.7 mm machine guns were specified in the MAC. "The weapon must:

1. Be an adaptable and self-portable light machine gun.

2. Enable effective fire against helicopters or light aircraft which are at an altitude of 1000 meters.

3. Range adjustable up to 1000m and 2000m.

4. Be lightweight for easy handling.

5. Be easier to maintain and operate than the US 12.7mm MG.

6. Use the different types of ammunition of 12.7 US (especially armor-piercing rounds to allow the MAC-58 to be used in an anti-materiel role).

It will not be studied lookout for new shooting ground, the lookout US ideally suited. Regarding the first specification, the vehicle is currently not defined and self-LMG in the study. "

The MAC should provide for 25 August 1956 at the latest, an information sheet containing the following:

a) the main features of the prototypes, b) status, c) when the prototype will undergo their next experiment the Institution of Experiments Techniques Versailles.

8354/ET/MAC by letter of 23 August 1956, the MAC has sent its response to the demand for ST / ARM:

2. The prototype is provided for feeding from the left output of the link belt and ejecting shell casings from the bottom right.

3. Effectiveness of air target shooting is to be identical to the 12.7mm MG currently used in groups of Light Anti-Aircraft gunners

4. Shooting ground is set with bezel APX 806.

5. Weight is comparable to that of the Hotchkiss M1914 machine gun, or 27.5 kg with a heavy barrel.

6. Principle is based on the AA 52 with few parts

7. The gun should fire both NATO and French cartridges

8. It is mounted on the M3 tripod by a flexible MAC link

9. Its fire rate is 500 to 600rpm.

Two prototypes were presented to the CABA, 30 November 1956 for a first prototype, the second was sent May 28, 1957. It contained only a few detail improvements, made as a result of tests on prototype # 1. On 27 June 1957, three machine guns were sent to complete the CABA. Two copies were for the Technical Section of the Army. The weapon was found valid in its presentation and its operating principle, but it could be mounted on all military vehicles in service because of its shape and organization (no rear handles). On December 10, 1959, the prototype No. 7 and 8 were given to the Atelier de Construction d'Issy-les-Moulineaux for adaptive trials on a circular troop transport vehicle. Ultimately, 12 prototypes were ordered in December 1956 made and experienced. The weapon remained as the prototype for the development was not considered necessary.

• MAC-58