Old Dog: Yes, so many people simply repeating 'hearsay' about different types of ammo.
Do most people know that Residue is reported to build-up far easier around rigid steel cases, compared with expanding brass cases?
Guys who allow far too much accumulation when using steel might have found that after the gunk gets thicker, they switch back to expandable brass, these cases then "puff out", get Stuck, in said residue---
--because they didn't want to do a bit of chamber scrubbing when using rigid steel. A gunsmith reported this on "PerfectUnion" (Mini 14/30 chat etc) in 2008, along with others.
Cases, lacquer or polymer-coated, primers, powder loads, bimetal (zinc over thin steel) coatings on bullets...many people >> don't Specify which factor(s) << they are trying to ask about.
jrmiddleton425: and so you are suggesting that your CZ is made of high-quality steel, well-designed components, tougher than the softer, cheap steel used in the lowest-cost ammo? This idea is 'over the heads' of so many.
Not many of those people with the concern
about steel ammo seem to have much faith in their >> Modern guns' designs <<.
Again, my newish Czechpoint VZ-58 in 7.62x39 just passed the 1,500 rds. (Russian ammo) milestone, and nothing broke ! It seems perfect, and still feeds, fires, extracts & ejects !
A guess? No-I keep a piece of each 20 or 40-rd. ammo 'box' in a labeled plastic bag.