What do you mean by ported on the air valve and on-off? The only porting that should be done on an AIR valve is with the old ones where a single hole needs to be drilled in the back half so that it lines up with the hole in the front half. The on-off needs nothing.
A mag valve needs at least 600psi for a level 7 bolt to work properly. A low pressure tank won't provide enough pressure.
Make sure the velocity is turned up enough. When you hold the trigger against the safety, is there a tiny gap between the back of the trigger and the front of the trigger rod?
Is the rail bushing in place?
Except for the Automag in front, its usually the man behind the equipment that counts.