Originally Posted by bugeyes
One problem though is sometimes the casing won't eject, i pull the bolt back and it gets pulled back but it doesn't get thrown out of the rifle it just sits there.
Classic fault caused by a weak extractor spring. Replace it.
I have no idea what an "ejector plate" is but I can assure you that a Lee-Enfield doesn't have one to get worn.
Contrary to a previous post, the ejector screw is only used for ejecting unfired live rounds. Fired cases do not use it, relying on friction of the case rim on the wall of the receiver, powered by a strong extractor spring!