A .38 Special loaded to a cartridge overall length of 1.58"-1.60" is essentially a short-brass .357 Magnum. A .38 Special powder charge, (with a few exceptions),is not appropriate.Another problem is that the bullet will not be seated very deep in the case, won't be crimped,and poor ignition may result. Conversely, deep seating a .357" bullet in a Magnum reduces case volume and will cause a serious overpressure condition.