Either you will have a shooter or not. These guns are very mass produced and the quality control is not what the more expensive guns are. NEF has made improvements in the extractors and other areas.
The problem lies in the way the hinge closes. If it is a good snug fit and is not sloppy great. Leave it alone. Take it out and shoot it and see what you have.
Here is a link to a factory tour http://www.backcountryjournal.com/h&r1871firearmsfactorytour.htm
and a link to a forum with lots of info on these guns
http://www.graybeardoutdoors.com/phpbb2/viewforum.php?f=126&sid=f985fee69a7922eb6565cc 6a7f465f60