You can find a lot of information about these rifles in the M1A / M14 forum at
http://battlerifles.ambackforum.com/. This question comes up frequently over there.
I had one of these rifles for about 12 or 13 years. It was one of the Fed Ord M14s that was assembled with Chinese parts. I never had a single malfunction with that rifle and it was at least as accurate as the M1A that I replaced it with. I still am not sure I should have sold it.
My advice would be to have the rifle checked out by a competent gunsmith WHO KNOWS M14S! If it were mine, I would send it to
Smith Enterprise. If it checks out OK, shoot it and see how it functions. Some of those rifles are good even though most internet "experts" will dismiss them outright even though many of them have never even examined or shot one.
If I remember correctly, there are 2 kinds of Fed Ord rifles. 1 type was built using GI parts, the other type was built using surplus Chinese parts. The main problem with these Chinese parts rifles appears to be soft bolts that will set back over time and cause excessive headspace.
Some of them just have so many dimensional problems with the receivers that they cannot be made safe and this is what you want to find out from someone like Smith Enterprise. I hope your friend's rifle is not one of these.