Nordic Components has a PCC with interchangeable magwells that take different mags. I don't think they have a P320 variant but they may be making one in the future.I've been searching for a PCC/AR9 lower that will accept Sig P320 magazines?? Any manufacturers out there?? I seen a video that Fight Lite has a MXR coming this year -- they don't declare what Sig mags it will accept.