First off, neither of these guns is going to blow up with SAAMI loads. However, IMO, these guns are on the ragged edge for SAAMI loads. I'd shoot CIP if I could get them or Id' reload and limit myself to around 8500 psi. The SAAMI loads may shorten time to off-face. Relatively modern is somewhat better, but these are still traditional designs with traditional steel,far as I know.