I'm kicking around the idea of rechambering my CZ 550 375 H&H to 375 Weatherby. I need a 500 yard rifle where I hunt. I can't seem to get the speed I want, or the accuracy out of the Barnes 250 TTSX. Rifle simply hates the 260 Accubond. Although it loves the 270 TSX at 2600 fps. My dilema is that I don't know if the TSX has the speed to open up at 400 yards. Has anyone done the conversion using the factory barrel with the CZ?(Sorry for the hijack OP)