I have an IMI Uzi that is having some feeding and ejecting issues.  After some research I've narrowed it down to most likely the ejector, but still need to check it out and not sure on the feeding problems.  Any other suggestions?  I made sure the barrel nut is tight and I've tried 4 different magazines.

Is it a select-fire gun?

The ejector is a piece of sheet steel riveted to the grip frame. Make sure it's straight and aligned with the bolt's ejector groove, and not rubbing. Also make sure it hasn't been bent down, so the tip is horizontal and hitting as much of the cartridge case rim as the bolt's ejector groove will allow.

Uzis tend to function better with stronger ammunition, especially in the semiautomatic Uzis. What ammunition have you tried?

It's a semi auto.  I will have to look at the ejector a little closer to make sure it's ok.  I only had Herter's and Federal brass cased ammo with me to try.

Like Karl suggested. Try some warmer ammunition. Winchester Q4318 (124gr. NATO) works GREAT in both my model A and Vector/Group SMG.

What are the specifics of the ejection malfunction?

I've seen some semi uzi's that are having feeding problems have a corner so sharp on the lower edge of the bolt, that as it strips a round, the next one comes up, and the sharp lower edge of the bolt digs into the casing of the next round, slowing down the bolt.

Another vote for running warmer ammo. Most American ammo would produce weak ejection or FTEject in my Uzi.

AJ

The extractor could also be the cause.  They are kind of stiff when new and need breaking in. Shoot a couple hundred rounds of hot ammo as stated above, and your problems will likely go away.

Are the FTF issues coming from both sides of the mag?....or just the L or R ???

Take the top cover off of your gun, take out the bolt, insert a mag with 10 or so rounds in it and watch what happens to the round on the (L) side as opposed to that on the (R).....

The ejector sometimes has a tenancy to force the (L) round slightly forward....which cants the nose up and the "ass" down....and can sometimes result in a FTF.

Everyone is quick to go the top-cover gap route when talking about FA or SA Uzi fixes....then move on to chamber dimensions/etc.....but I can honestly tell you that I've shot plenty of clapped out (original) FA IMI Uzi's with obscene top cover gap, stamped feed ramps....and those horribly small feed "throats" that original IMI FA barrels have.....and they never miss a beat.

The biggest problem I have seen with Non-IMI, or Non-Vector/Group guns (with known receiver issues), is proper magazine height.....due to the lack of the grip housing being properly fitted to the receiver, and the mag catch being improperly adjusted.


eta: Use some HOT 124gr 9mm next time you troubleshoot

When I hand cycle through my CAI Uzi, (for emptying a magazine for instance) I often get feeding and ejecting issues.  But when I am actually shooting, it's flawless.