French Chauchat Machine Rifle CSRG 1915

Me firing my recently receive CSRG 1915 chambered in 8mm Lebel. I ve only tested it so far with one ammunition type, a reloaded Graf s 8mm round which may not be sized correctly, only time will tell. I have three other types of ammo to test. Note that these failures are not related to the heat expansion issue experienced after prolonged fire, but are during the extraction phase. The brass showed apparent expansion, pointing to undersized brass perhaps, or a chamber that has grown too large due to prolonged br, br,