No problem, Jim. I sometimes have a tendency to forget that some people haven't been loading as long as I have and aren't able to experiment with their loads.
I was looking in the Sierra 50th Anniversary Edition of their loading manual, which happened to be handy by my computer, and they list plain .38 Special loads with a 158 grain bullet at velocities ending at 1000 fps, with a variety of powders. Under the data for the .357 Magnum, they list quite a few loads for the same bullet starting at 1,050 fps, which for this discussion is pretty close to what john1911 was asking for. I figured you could just drop back a skosh (that's an official loading term, by the way) and achieve the 1,000 fps of the .38 Special load and be good to go. They listed 8 common powders at the 1,050 fps level for the Magnum case, which would work, but they are all heavier charges than the .38 Special loads for the 1,000 fps level in the .38 case. It's pretty well understood that the larger volume of the .357 Magnum case will require heavier charges to achieve the same velocity, which is what was stated in the original post. And all he really asked was if he was safe in using .38 +P loads in .357 brass, and if he would run into any trouble if he did? The answer to both questions is "yes, he's safe" and "no, he won't run into any trouble". He just wants to spend more time shooting and less time cleaning his guns. It doesn't appear that he's trying to achieve a particular performance level, per se.
Hope this helps.
Fred