I have read a lot about Ruger's Mini-14. Quite a few people say that you should not use steel-cased ammo in the Mini. Well, I just happen to have several cases of steel cased Russian .223/5.56. It is 62 grain and has steel cases. Does anybody here know of any problems using this ammo can cause? Does it break firing pins? Is there some other problem? I just checked Ruger's owner manual for the Mini and all it says is to use ammo manufactured to American standards. Opinions, please.