I have been trying to figure out something , how does a person go about developing a charge for a hand gun. I will use .357s as an example ; I shoot a 150 grain bullet and am wishing to develop load of unique to push that bullet .A guy who I respect deeply told me to look at 2400 powder for that same bullet, however my local gun shop did not have that powder. I have used bullseye powder to push that bullet before , and it is even listed. However that gets me to the question , how is it possible to develop a load of unique to push that same bullet. I have read multiple places that signs of over pressure are greatly exaggerated , and to be honest , since I normally load everything light , I am not sure that I would have a clue what was an overload or not ... well until there was an earth shattering KaBoom. Another problem that I have run into , That bullet is listed for .357 magnums , but not for my .38specials , so once again how to develop that charge. I have been loading for a number of years, but this is something that I have tried to figure out , especially since there does not seem to be a consistent movement of powder charges, ie , if the bullet weight goes up , should the powder go down , that seems to be the most common movement , but not always. I have been shooting my own charges that I have guesstimated to be good, but there has to be a better way to find out what a person needs. I wish that there was a way to plug in a bullet and a powder into a program and come up with the numbers, but I have not seen such a chart as of yet.