WHAT DOES RED ARMY STANDARD 7.62×39 MEAN?

Fired flawlessly by way of my Glock. At 21ft went from ten inch groupings all the way down to 2 in groupings using this stuff then back again to 10 inch groupings following I applied it. Obvious as working day these things is accurate with practically NO recoil. Would not want this inside a tactical circumstance but in order to see how precise you