The biggest problem with shooting steel case through an AR is gas blow by.
When fired the steel case doesn’t expand like the brass ones do, leaving a gap for hot gases and carbon residue to go. The carbon builds up with each following shot, eventually leaving what looks like a moonscape in the chamber.
Invariably a brass case is fired and expands into the crevices and crannies.
The bolt carrier moves rearwards trying to drag the bolt and fired case with it.
Depending upon the case, you either pull through or pull off the case rim leaving the fired case stuck. Or the extractor breaks, rare but it does happen.
My problem with most steel case ammo, is that the powder charges vary greatly, and bullet diameter and weight are not consistent.
The exception to this is the Hornady Action Pistol (?) loads in which they imported the steel cases and loaded them here with consistent powder charges and good bullets.
As an aside, People forget that the majority of the .45acp ammo used from 1943-1945 and beyond was steel cased.
Evansville Chrysler put it out by the millions.
They actually stopped production before war ended as the government had such a large stockpile.