Belom 7.62X39mm, 123 Grain, Full Metal Jacket, Brass Cased, 20 Round Box BEL8606110608093 Some of the finest brass cased 7.62x39mm you've ever seen. Made in Serbia, the Belom 7.62x39mm 123 Grain is a Full Metal Jacket round. These are packed in an ingenious polymer tower with the Belom crest molded on the top, 20 rounds to the box.