As stated before, if it is marked +P then it is rated for it and the warranty should cover any defects resulting in damage. But… Is it worth the extra wear and tear for the mild uptick in velocity? I don't mean to sound preachy but if more people would buy a good .357 and shoot .38, .38 +P, and .357 magnums there wouldn't be so many worn out .38's out there. Most .38's don't get anywhere near the grade of steel or heat treatment needed for the added pressures involved in +P. Top it off with the fact that modern HP ammo opens at lower velocity and penetrates deeper than it did even ten years ago.