my friend bought an xtra last night on ebay, it's got a 12oz, physco bullet drop, and AA vigilant low pressure reg($90 total, cheap)., he said it said it runs under 400psi. and would get 1000 shots on the 12oz.er, to make it a read low pressure system, does he have to get a low pressure chamber/volumiser? i think he does and i told him this, let me know here