What you read about not shooting a lot of hot .357 Magnum ammo in your S&W M-19 is correct. Designed with the law enforcement market in mind, the M-19 was based on a .38 Special design. It was intended that .357 Magnum ammo would be used for duty by that .38 Specials would be used for other purposed, i.e., range, training, etc. Shoot it with any .38 Special load you care to use and it is likely that M-19 your grandson will hand it down to his heirs. Some use of .357 Magnum ammo will cause no harm. I would personally use the 158 gr. JHP loads. The 125 gr. .357 Magnum loads have a reputation for damaging revolvers due to flame cutting of the top strap and cracking of the barrel forcing cone. HTH. Sincerely. brucev.

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