I am working on duplicating the orig. Hornady 10mm XTP vel. My results from my range trip today. Air temp. 70deg. G20 w/stock brl. 22# Wolf spring. C.O.L. 1.260 155grXTP 12.4grs B-D 1386fps, 180grXTP 10.5grs B-D 1196fps, 200grXTP 9.4grs B-D 1126fps Very happy, the 10mm is a very versatile cartridge. BTW, I am not trying to produce Nuk loads.