I seen a guy on predator masters that did a 257 wildcat on the x47 case. IMO this is the best usable upgrade over the other cases out there. I think this wildcat makes the most sense in a 6mm version and a 22 cal version. near 22-250 performance. I hope the day will come when there are plug and play parts out there to build a standard bolt face ar varient. another interesting one is based on the br case