So we have all been told that you shouldn’t shoot 5.56 mm out of a .223 rifle. Does anyone have any experience with this? Has anyone ever experienced a failure from using 5.56 in a .223? I have a savage bolt action in .223, I have shot 5.56 through it without a problem. I could even tell the difference between the two when shooting? Manufacturers tell you not to do it just for liability purposes. They also tell you not to shoot reloads or hand loads through there rifles but everyone does.