I bought a Remington 870 Express a few months ago. I had heard of people having problems with cycling but mine didn't have a problem after the first 300 rounds. After the 300, I decided to give it my first real cleaning, other than just the bore. I did not disassemble and field strip, but I wiped the inside with No. 9 solvent on patches, then lubed with RemOil.
After doing this cleaning I went shooting yesterday and started having problems with cycling. By placing the gun in my hip and pulling the pump as hard as I could I could get it to cycle. It didn't do it with every shot but about every 10 stuck. Towards the end, the extractor failed to pull out the shell and just ripped the plastic around it completely, leaving the spent shell inside the barrel.
I would like to figure out if anyone has had any similar problems and if so what you have done to fix the problem.