The receiver is metal on both but the finish on the old is smooth and the new ones are textured.
The trigger group is plastic on new ones, also the hammer and hammer bushings are one now where before it was hammer and two bushings.






Quote Originally Posted by Mobat555 View Post
I was unable to find a clear distinction of what makes the older ones special. From what I read above I am guessing it the trigger group housing being metal is there anything else about them that makes them better? Are the new ones really just plastic now?

This is what mine looks like:
Bolt
Trigger Housing

Guessing its a good one.