I know velocity increases with temperature, but does anyone know of a good rule of thumb? Specifically, I have some 9mm Bullseye loads that are getting 950 fps with a 124gr bullet (Bayou Bullet, if anyone is curious). I was out shooting it in 25-degree temperatures, and my goal is to make IDPA power factor, which is gonna require around 1010 fps, preferably a little more just to be safe. I'm pretty sure I'm gonna have to boost my load a bit, so I loaded up some more that are an additional 0.2gr of powder, but I haven't had a chance to chrono them yet, since it's BLOODY FREEZING outside and I value my fingers and toes. Can anyone give me a guesstimate for how fast they'd be in more reasonable shooting temps between 40 and 80 degrees?