Really. Four years ago I'd bought some Russian in 223 and tried to use it in my AR180 to qualify. Now you have to remember we police tend to rip thru a goodly number ofrounds at a pretty fast clip. One magazine and then the polymer seized in the chamber and it took several blows on the charging handle to dislodge the spent case. Next round was the same. In our pistols, they work fine, but in a rifle, never again for me. My life is way to precious.