Found some surplus 7.62 at a garage sale last fall. 500 rds for $5. Anyway in each 20 rd box, 10 are marked H1 7.62 and 10 are marked H0 7.62. It is European as it as the two small widely spaced flash holes, annealed necks, crimped primers with green sealant. The bullet is 140gr BTFMJ with 45 grains of what appears to be rolled ball powder. The boxs are marked 7.62 20 rds with a smal Nato cross on the bottom corner. My M305 will group 5 shots in under an inch with this stuff. What is it and where the heck can I find some more? 