We in Russia are compelled to shoot poor-quality cartridges.
We have resource where characteristics and targets are published.
http://www.ada.ru/Guns/ballistic/223Rem/index.htm
Hornady, Hirtenberger, Winchester, Lapua, Federal - it is much better.
Compare targets and all becomes clear
http://www.ada.ru/Guns/ballistic/223...T223/index.htm
http://www.ada.ru/Guns/ballistic/223Rem/SB/FMJ.htm
Can be, Czechia deliver on our market a second-grade cartridge.
Selling people. Well, they now in NATO.
Still it is possible to smoke the Bulgarian cigarettes, but for this purpose it is necessary to not love itself very much.
Good luck.