First before he does anything he needs to go to the post visitors center to get his rifles registered with the MPs. Once he gives them make, model, caliber, and SN he can legally take them on post. He cannot store his weapons in his vehicle or his barracks room. He needs to go through his chain of command to get a memorandum signed by his company commander or company executive officer allowing him to store his weapons in the company arms room. Once the memorandum is signed he can store his weapons with his unit. The only thing that is bad about it is that the unit Armorer is the one in control of when your son can get his weapon since the unit Armorer is the ONLY ONE who is legally allowed to access the arms room. So to recap, step 1. Register weapons on post at the visitors center. Step 2. Go through COC to get privately owned weapons on the company memo to store in the arms room. Step 3. Store your weapons in the arms room. Assuming your son is a PVT or SPC his squad leader or platoon sergeant can get the ball rolling for him. He just needs to ask for their help. I hope I helped with your question.