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Companhia Brasileria de Cartuchos, CBC, says its 7.62mm x 51mm cartridges from lots dated 1975 pose serious safety risks because of excessive pressures. The cartridges, headstamped "CBC 7.62 75", should not be used, given away or sold under any circumstances. There have been reports of rifles bursting as a result of the excessive pressure. An independent testing lab detected peak pressures in excess of 130,000 CUP, in one of 20 of the cartridges it tested. CBC calls these rounds outdated.
The particular round was manufactured solely for military use in several countries. They are not intended for civilian use at all.
CBC also has issued a warning for any of its 7.62mm x 51mm cartridges from any year which have a label on the packing material with the Spanish word "reengastada." The label was not affixed by the manufacturer and its application to ammunition is unclear.
If you have any ammunition with the 1975 headstamp or with the Spanish word, contact CBC at 800-742-1094.
– Originally published by the author, un-bylined, in the 1 June 1992 Firearms Business.