Ok, I have a freshly built Rock River carbine that does not want to work correctly.  Here are the symptons:

It will fire no problem. Ejection is quite vigorous, but it does not seem the hammer is properly resetting.  All I have to do is pull slightly back on the charging handle the rifle will function again. So, in essence, I have a straight pull 9mm bolt action carbine. Any suggestions where I might look?

BTW, I am using an A4 upper carbine on a Rock River lower. The mag block is a Hahn top loader, along with a Rock River hammer and 9mm buffer.

Is it the hammer that is not releasing from the disconnector?
When I built my RRA 9mm on a MEGA lower, the hammer did not release from the disconnector .  Very  (read very again) light stoning on the rear hammer hook solved this.
Remove the upper from your lower and work the trigger/ hammer to see if  the disconnector is working by releasing the hammer when the trigger is released properly.

PROTECT THE LOWER FROM FALLING HAMMER WHEN DOING THIS, LETTING THE HAMMER DROP AGAINST THE FOREWARD FRAME CAN CAUSE DAMAGE!