Firing pin protrusion out the bolt when the FP is seated against just the back of the bolt should be between .032 and .037.
Next, did you forget to install the disconnector spring. It should have been installed with the large coil side down into the back of the trigger slot, and the hammer will not reset if the disco spring is missing.
Regarding the hammer spring, are the coils winding out the correct direction? Also, did you check the J spring in the hammer to confirm that it's walking out, catching the front of the receiver and the reason for the light strikes?
Also to point out, the primer is going to have a slight dent at loading (it's normal from the floating firing pin) and what you may think is a hammer strike, may just be a loading dimple alone. In this cause, something like the bolt not fully locking up will keep the FP Blocked form reaching the primer (back of the carrier blocking it out of position since the bolt is not lock up) and although the hammer may be falling to strike the FP, the FP will never reach the primer.
http://www.ar15.com/content/guides/assembly/lower/