I contacted Wolf Ammo and was told that they guarantee thier ammo but that you should check with your firearm manufacturer on thier recommendation for what ammo to use. Olympic arms warns not to use steel case lacquer coated ammo, I have heard that Bushmaster warns against its use. I contacted DPMS and was informed they have no problem with this type of ammo. Brass cased South African ammo is so cheap right now, why take the chance in damaging your rifle??? For about $10.00 a case of 1,000 more than steel case you can have brass, that equals one cent a round for a less likely chance of ruining your barrel/chamber/extractor.