I have shot plenty of Tula.
It tends to be a little under powered due to the powder they use and this can cause some feeding issues.
All my AR's will shoot it 100%, and i would not want to own an AR that won't fire it.
That being said, the bullets are generally bi-metal, meaning copper coated steel.
This tends to cause more barrel wear than copper coated lead. -yes, I have seen the torture test
Not a huge concern, but it is a concern to me, so I don't shoot it much.
The big problem with steel cased ammo is that is does not expand as well as brass, so you do get more powder residue build-up.
If you shoot a bunch of steel cased ammo then switch to brass without cleaning, you may get a stuck case.
(this is how the whole "lacquer melted" thing started.)
$5.99/bx for steel Tula vs. 6.99/box for brass American Eagle
.05/rd for ammo that is better and you can collect the brass and either reload it, sell it to a re-loader or scrap it for cash and it is generally cleaner and more accurate ammo.
I went to Battle Rifle Co......located in Webster, Tx...... to give my AR a face lift and they told me NOT to use steel case ammo as the lacquer gums up the firing chamber
That is an old gunshop tale.
But, most Russian ammo is not lacquer coated anymore anyways, they use a polymer coating.
Tula is polymer coated.