IronGeek, why are your first rounds composed of less powerful .38 spl and your last rounds .357? You mentioned the .357 for finishing the job. That is fine, but what makes you think you will be able to fire the other rounds to get to the .357? Heck, if you do get to shoot, what makes you think you will get off more than one shot? Wouldn't the prudent avenue be to end the conflict with the first shot of .357 as opposed to building up to using the .357?
I have read several tales where LEO and non-LEO folks have managed only one or two rounds in a fight before something happens such as their gun malfunctioning, their gun being struck by incoming rounds, the gun being lost in a scuffle, or the operator of the gun going down. In some cases, the operator did manage to hit his opposition, but the strike did not incapacitate the opposition and allow the opposition to operate long enough to harm or kill the good guy.
It is your call, but saving the best for last in a fight is not prudent. The longer you are in a fight, the more likely you are to be harmed or killed.