I got this from Remington
Question
My Model 1100 or Model 11-87 Premier is not cycling properly, what can be the problem?
Answer
There are many items that can affect the cycling of an autoloading shotgun. The Model 11-87 12 gauge shotguns with field barrels installed need a minimum of 3 ¼ dram and 1 1/8 oz shot to properly cycle.
The Model 1100 barrels are normally chambered for either 2 3/4" or 3", not both, and will only cycle that one length shell.
Some components that you can check are:
Barrel seal-make sure that it is in good condition and properly installed on the detent as shown in your owner’s manual
Piston/piston seal assembly-make sure that these are also in good condition and that they are in the correct position as shown in your owner’s manual.
Action Spring- this is the spring that is located in the action spring tube that runs from the back of the receiver through the rear stock. This can become corroded or gummed up with oil and debris over time. Waterfowl hunters especially should check this part of the firearm regularly. You will need to remove the stock to access the action tube.
Gas Orifice Hole – Ensure that it is clear of any debris by cleaning with a small pipe cleaner.