These are not jacketed, but plated. I don't know much about them, but I found some in my supplies. They look jacketed but no crimping groove. With the lack of regular lead bullets I am tempted to try these. I wonder if they need a special die like maybe a taper die because I don't think a roll-crimp like for regular revolver ammo is appropriate here. I load for .38 Special. I've got 250 of these bullets, if I know what to do with them.