I steel-cased 7.62x39 back before cheap surplus ammo was widely available. Here are the downsides:
1. steel cases are much more difficult to resize and expand. good lubrication is a must. YES, they are hard on the reloading dies.
2. If the original primer is the European Berdan-type, depriming will require special tools. New primers are in odd sizes, and much more expensive than US Boxer primers.
3. Neck splits are common unless you anneal frequently.
4. The lacquered finish is what prevents the case from rusting. The US Military has ammo specifications with zinc and chromate coated steel cases for war contingencies when strategic materials like brass and copper are in short supply. They are not normally used. Yes, scratched cases rust easily and will abrade your chamber and extractor.
5. Steel cases are harder on automatic gun mechanisms, namely the chamber, extractor, ejector and feed devices. They have greater chamber cling and higher extraction forces. Broken extractors are common. Note that small arms designed for use with steel-cased ammo have massive extractors (AK, AKS, etc).
6. Your .223 cases are probably Chinese or Russian Wolfe brand production. Forget them. they are not very high quality to begin with.
In short, it is simply not worth the time and trouble to reload steel cases unless the cartridge is rare or brass cases are not available.
