I can understand steel core limitation at gun ranges, but steel case damaging your weapon, a lot of misconception.
Box of Truth did some testing on the same issue...
The Box O' Truth - Educational Zone #18 - Shooting Wolf steel-cased Ammo in an AR15.
I've shot steel case ammo (non-lacquer coated) in my Glocks, Witness, Taurus PT709, DPMS, CETME, AKs and SKSs no problems.
We are talking thousands of rounds each over that last few years not just a box or two.
I have a friend that shot over 5000 rounds of steel case in his STAG AR-15 and absolutely no issues.
The only weapon I have and still having issues with that has never touched steel case, only brass are my Remingtons.
I have a 7400 and VTR both in 308, that have both had extraction issue with brass only ammo.
I am on the second extractor replacement on the 7400.
Seems it says more about the weapon than the ammo.
As for lacquer coated ammo, I don't know if my Mosin sticky bolt is from the lacquer coating or all the darn cosmoline.
I will say that the chambers are free of lacquer and more the problems are in the lugs.
Can't see how the lacquer coating from the chamber gets from into the locking lugs but that is not a steel case issue, but coating.