Who can actually repair one so it feeds and ejects properly ?
I got a beauty and it shoots beyond belief. But, sometimes a fired case will not eject. I've had it to 3 gunsmiths but no luck yet.

These are "cranky guns" I'd suggest the guys at Gander Mountain...they have all the right stuff to work on these...if you can, ask for Jim Kramschuster (krammy)

I bought a brand new 100 in 1965. To date it has functioned flawlessly. I kept hearing about people have trouble with them and calling them "jammamatics". I did a little research and found there was, IIRC, three different extractors that were installed in these at different times. I had bought up about 8 of these extractors, all three designs and had the info on the bags for what S/N range they went to. I think what was happening was they were putting different ones in different rifles and this is what caused the problem. Unfortunately, I don't have any left nor do I have the correct extractor/S/N info. Maybe Jim Wisner can chime in on this.

Guys,

In the old days we fitted new bolts and extractors under warranty for Win. A couple of things to look for is: check the gas block on the barrel and see if it is leaking around there, the fix was to use 440 solder to stop leaking, check chamber for rust and polish if needed, on the extractor there are gages to use to check the fit under the extractor. When the guns had a few cases stick the extractor would wear under the bolt face retainer lip and have too much loose fit that allowed the extractor to slip over the case. The dimensions for the gage on these bolt face lip was around .055 to .058. Someone with the service manual may have the exact sizes and post them. These guns had a habit of auto fire at time also. These are not easy to work on and Walt Phillip factory service manager would come by the shop we would spend all day going over the Win. problems and the fixes. Oh for the good old days!!!

I also had a 100 with jamming/extracting problems I took it to two smiths that said they had the cure all and it never solved the problem. So with the help of the NRA guide to dissassembly I tore it apart and cleaned every single part after putting it back together it performed flawlessly

Winchester had a recall on the firing pin several years ago, I believe you can call with the serial number and see if it was repaired.
Brownell's sells a new piston assembly for the 100 which is suppose to restore the functioning and it could be a bad magazine which you can still find if you look.