You always want to go with reliable, published sources, so I'm going to point you to the Hodgdon reloading center. Hodgdon now handles all Winchester, Hodgdon, and IMR powders. Hodgdon Reloading Data Center
That's a fairly extensive list, but they don't show 115 FMJ per-se. You'll want to use the load they show for the 115gr Speer GDHP. The Gold Dot hollow point is a heavy plated bullet, but it loads like a FMJ. They just expect you to know that.
Another bit they expect you to know is that Hodgdon HP-38 is the exact same powder as Win 231. Sometimes they show one, but not the other. When you shop, you'll usually find that HP-38 is 1 or 2 bucks cheaper than 231. So when you're buying Winchester brand powder, you're paying extra for the name.
Obviously the GDHP is not going to shoot exactly
like a FMJ, so begin at the starting load and work up in small increments.