Ranger 76,
No offense, but either something is wrong with your chronograph, or you have the fastest model 19 on the planet. I've tested lots of loads through lots of 357's over several different chronographs, and that's not even close. Real world numbers are more like 1200-1300 with that load. I currently have a Model 27-8 3/8" that takes 17.0 grains to do 1275 with that bullet weight. Same load goes about 1000 out of my 3" mod. 66. That load may break 1500 out of a 10" non-vented barrel, but a revolver- no way.