Fusil de Infanterie Modèle 1907-1915 Modifié 1934 
In 1932 both Manufacture Nationale d'Armes de Châtellerault (MAC) and Tulle (MAT) began work on this new conversion, to be called the Fusil d'Infanterie Modèle 1907-1915 Modifié 1934 or simply “M.34”, after a series of testing at both Camp de Châlons and Camp de Versailles it was adopted for service in early 1934. The weapon was to retain the typical Berthier lineage but was modified to the following major components: the barrel was replaced with a new 570 mm (22.4 inch) chambered for the Modèle 1929C à Balle Ordinaire otherwise know as the 7,5x54mm; both the front and rear sights were changed to reflect the change in the new caliber ballistics, the rear sight leaf and base was changed to a sliding ramp type which was graduated from 200 to 900 meters; the bolt head was replaced with one that was able to support the base of the rimless Modèle 1929C and a movable type ejector added; hand guards were added to the top of the barrel and with this a new lower barrel band and hand guard retaining ring near the receiver was used to hold it in place. The biggest modification however was the magazine system which was changed to a 5 round staggered-column box type with a spring loaded follower and solid floor plate. The top of the receiver was notched with charger guides so that the magazine could be loaded by the use of a charger/stripper clip. This new rifle was 1,075 mm (42.32 inch) in overall length and weighed 3,700 kg (8.15 pounds). There were two different variations made, one for the infantry and one for the cavalry. The difference between these two was the sling placement, the infantry model had the typical under mounted front and rear sling configuration and the cavalry model utilizing the sling bar and concentric ring mounted on the left side of the weapon. Approximately 65,000 weapons were converted to this new system from 1935 to 1939 and 90% converted were the infantry version. The bayonet used on the models was either the Epée-Baïonnette Modèle 1886 Modifié 1915 Raccourci 1935 or Sabre-Baïonnette Modèle 1892-1915 depending on the variation of the model. Most of these rifles were issued to the Fortress Infantry such as those who were stationed on the Maginot Line.
More information can be found at this link: http://armesfrancaises.free.fr/FR%20Mle ... 20M34.html
F 131 - Left side of barrel: AEG,Circle 'B'; Right side of barrel: MAT 1935; Bottom of barrel: Circle 'B',E ... Waffenmapts are present under Circle 'B', under Mle, next to Cal 7,5 and on stock behind the triggerguard. ... owned by French moderator 1886lebel
F 64X - MAT 1936/5 metal AEG
F 16916 - AEG, MAT 1936 (+5, 'B', "E")
F 220XX - AEG, MAT 1936 (+5, 'B', "E")
F 27182 - MAS 1936 ("LK5")
F 34734 - MAS 1937 (from seller's description) Cut-away rifle
F 5368X - MAT 1938/ no month
F 5754X - MAT 1939/ no month
F 5811X - MAS 1938/12
F 599XX - MAS
F 6090X - MAS 1939/6
F 61059 - MAT 1939 (Upper L/H barrel, "C", circle "9")
F 6302X - MAS not readable