Depends on the firearm to me. I shot some Brown Bear steel case in my old Bersa CC Thunder and it started to eat the feed ramp because it was an alloy which I did not know since the company claimed it was a steel gun. This is where I would generally rant about my beef with Colorado Gun Works and how much I despise how Bersa handles their warranty work.
IMO, Ruskie ammos for Ruskie guns. The ammo is VERY dirty at the least and has caused my CZ to jam so bad it would not fully chamber a round. It can also be hard on the extractor but I believe this to be relative to the frequency. But the AK is a hungry beast and loves anything you feed it
