ArchAngelCD
Member.
IMO you have to try and figure out which powder speed the factory used and then match the velocity of the factory round.
Years ago I tried to replicate the 135gr .357 Magnum GDHP short barrel load and the 135gr .38 Special +P GDHP short barrel load. I spoke to a rep at Speer and she sorta recommended a a few powders for the .38 and others for the .357 Mag.
I settled on AA#5 for the .38 and Power Pistol for the .357. Neither were at the max charge weights, I used only enough powder to match the factory ammo velocity and accuracy. I did find replica loads for each and the .38 Special was most important to me because that is my carry ammo in my J frame.
I cheated a little and used a 140gr XTP bullet in the development since they were much cheaper and more available at the time. (was able to buy 200 for only $12/100 while the GDHP bullets were $23/100 at the time)
Years ago I tried to replicate the 135gr .357 Magnum GDHP short barrel load and the 135gr .38 Special +P GDHP short barrel load. I spoke to a rep at Speer and she sorta recommended a a few powders for the .38 and others for the .357 Mag.
I settled on AA#5 for the .38 and Power Pistol for the .357. Neither were at the max charge weights, I used only enough powder to match the factory ammo velocity and accuracy. I did find replica loads for each and the .38 Special was most important to me because that is my carry ammo in my J frame.
I cheated a little and used a 140gr XTP bullet in the development since they were much cheaper and more available at the time. (was able to buy 200 for only $12/100 while the GDHP bullets were $23/100 at the time)
