Well I am a retired Professional Mechanical Engineer, who spent the last 30 years managing industrial engineering and maintenance departments and being the number one troubleshooter on sites, and I have 30 years plus of working on Remington 1100s (and other stuff) as a licensed FFL. I never called myself a gunsmith because wood hates me, but I am a fair hand at gun mechanicing.
If the bolt is cycling properly, you only need that little bump to kick the shell out. It doesn't have to grab anything, just intersect the base circle of the shotshell. If you cycle the bolt manually with a shell - loaded or unloaded - and it kicks the shell out you're fine. And if the ejector button was worn, why did it work for a few rounds and then stop? I have rarely found mechanical issues to behave in such fashion. If the bolt is cycling and the shell is not ejecting, check to see if the extractor is chipped or broken. Only part (and only one of them) I have ever broken on six Model 1100s over 50 years and a couple of hundred thousand rounds.
EDIT - with some of the cheap steel based shotshells the base may grip the chamber so hard the shell will not eject until after it has cooled, if then. The chambers on mine are like mirrors and my guns will run even the Winchester Universals, but they rip about half of the bases doing it.
If the bolt is not cycling, it's a gas system issue or something is binding. A piece of masking tape on the receiver across the ejection port behind the handle will quickly tell you how far the bolt is moving.
The standard gas port size on a 12 gauge is 0.079" (2 ports). Magnum is 0.073" (one port - pre Steel Shot barrels), and Skeet is 0.086" (two ports) - with an admonishment not to shoot heavy loads. Check to make sure the ports are open with a drill bit turned with the fingers. A Magnum is designed to shoot 2-3/4" and 3" Magnum shells. Some will do better, some won't, and shells can make a huge difference, even if they have the same weight of shot and velocity. The pressure curve is the thing. I have a Magnum and it used to shoot any 1-1/4 ounce field load, but not any more because the shells have changed.
On older guns with a lot of use OR neglect, it is not uncommon for the outside of the mag tube to be worn. With the old style (original) gas piston and piston seal, they compensated somewhat for wear and still sealed, but the new snap together parts can be problematic - they are no doubt cheaper to manufacture, but in my opinion they do not work as well. Any new O ring should suffice to check it out, but as noted earlier for long life use the right stuff.
Remington used aluminum action spring followers for some years, and the grade/quality of the aluminum varied. It it becomes misshapen the follower can drag in the action tube and cause malfunctions.
If the fore end support (12 gauge) becomes bent it can drag on the action bars and cause malfunctions.
All I used for 20 years was WD-40, and that was when I was shooting competitive Skeet, and it worked fine. I now know there are a lot better alternatives, but the choice is not critical as long as it isn't real cold. Gun oil is the most overthought subject on the internet. No wait, it's tied with motorcycle oil. I spray my gas system stuff with RemOil and then wipe off the excess - I call it damp. Some people run them dry. Some people run them soaking wet. To be honest they all seem to work for the people who like their method.
If the bolt is cycling properly, you only need that little bump to kick the shell out. It doesn't have to grab anything, just intersect the base circle of the shotshell. If you cycle the bolt manually with a shell - loaded or unloaded - and it kicks the shell out you're fine. And if the ejector button was worn, why did it work for a few rounds and then stop? I have rarely found mechanical issues to behave in such fashion. If the bolt is cycling and the shell is not ejecting, check to see if the extractor is chipped or broken. Only part (and only one of them) I have ever broken on six Model 1100s over 50 years and a couple of hundred thousand rounds.
EDIT - with some of the cheap steel based shotshells the base may grip the chamber so hard the shell will not eject until after it has cooled, if then. The chambers on mine are like mirrors and my guns will run even the Winchester Universals, but they rip about half of the bases doing it.
If the bolt is not cycling, it's a gas system issue or something is binding. A piece of masking tape on the receiver across the ejection port behind the handle will quickly tell you how far the bolt is moving.
The standard gas port size on a 12 gauge is 0.079" (2 ports). Magnum is 0.073" (one port - pre Steel Shot barrels), and Skeet is 0.086" (two ports) - with an admonishment not to shoot heavy loads. Check to make sure the ports are open with a drill bit turned with the fingers. A Magnum is designed to shoot 2-3/4" and 3" Magnum shells. Some will do better, some won't, and shells can make a huge difference, even if they have the same weight of shot and velocity. The pressure curve is the thing. I have a Magnum and it used to shoot any 1-1/4 ounce field load, but not any more because the shells have changed.
On older guns with a lot of use OR neglect, it is not uncommon for the outside of the mag tube to be worn. With the old style (original) gas piston and piston seal, they compensated somewhat for wear and still sealed, but the new snap together parts can be problematic - they are no doubt cheaper to manufacture, but in my opinion they do not work as well. Any new O ring should suffice to check it out, but as noted earlier for long life use the right stuff.
Remington used aluminum action spring followers for some years, and the grade/quality of the aluminum varied. It it becomes misshapen the follower can drag in the action tube and cause malfunctions.
If the fore end support (12 gauge) becomes bent it can drag on the action bars and cause malfunctions.
All I used for 20 years was WD-40, and that was when I was shooting competitive Skeet, and it worked fine. I now know there are a lot better alternatives, but the choice is not critical as long as it isn't real cold. Gun oil is the most overthought subject on the internet. No wait, it's tied with motorcycle oil. I spray my gas system stuff with RemOil and then wipe off the excess - I call it damp. Some people run them dry. Some people run them soaking wet. To be honest they all seem to work for the people who like their method.
