Steel cased ammo almost always uses copper washed steel bullets which cut barrel life in half. Not only are they the least accurate bullets available they raise hell on the barrel rifling.
Magazine dumps, bump firing and other yahoo style shooting activities cut barrel life no matter what ammo you're using. Heat is the enemy of barrel life. The hotter any metal gets, the softer it becomes. Magazine dumps are like sticking a blow torch in your chamber with 55,000 to 62,000 psi. pressure waives being introduced with each shot fired. The barrel doesn't have time to cool between shoots, most gun powders create temperatures over 4000 degrees F. when they ignite in your chamber.
Clean your rifle thoroughly. Lots of passes with a brush the same way the bullet travels down the barrel. Remove the bronze brush after it exits the muzzle so as not to drag it through the crown. I would make at least ten passes. Follow with wet patches of solvent. After you are convince the barrel is as clean as you can get it, try some USA manufactured ammo to see if it will shoot it. If it won't you're SOL.
I won't shoot steel case simply because I'm an accuracy nut. But if it did shoot well I would still avoid it simply because of what it does to barrel life.