What is the loading diagram for a C-130J?
As listed on a CNI-MU emulator designed for use by C-130J loadmasters, the following is a list loads and moment arms for the aircraft:


Basic weight: 80,000 lbf/STA 530 
Crew weight: 600 lbf/STA 153
Fuel weight: 38,000 lbf/STA 551 -- this weight is, naturally, variable,
although the moment arm appears to stay relatively constant.
CG limits: 21-30% MAC


Finally, payload moment arms can be determined via use of of DD form 2130-2 on page III-V-17 of the 2015 Defense Transport Regulations (http://www.ustranscom.mil/dtr/part-iii/dtr_part_iii_app_v.pdf).