Another fix for sloppy remington quality control.
First of all, i have no idea what im doing and i dont recommend this to anyone, but feel free to try this if you are having the same issue:
Have you ever had a feeding issue when using short shells, maybe shells going sideways when chambering or falling off the ejection port? Brass not aligned with the bolt jamming the gun?
(Ever consider what would happen if you cycle the gun hard and your ejector claw hits the primer because the shell is in the wrong spot? Way to go remington..)
This might all happen because your elevator doesn't go all the way up, try cycling the action until the lift brings up a shell and see if the shell is loose - if it is, your lift isnt coming all the way up.
This likely happens because the sear in trigger assembly that controls the lift is not allowed to move enough because it is blocked by the part it is attached to.
You need to take the lift and sear off, easy to do. If you cant figure it out i would not recommend trying this "fix"

http://imageshack.com/a/img844/9527/3tob.jpg
Using a file or dremel tool, grind the part that stops the sear SLIGHTLY, and i mean SLIGHTLY, 1-2mm MAX, in such way that it allows the sear to come forward a bit more. You need to angle it correctly and grind it all the way from top to bottom where it touches the sear.
If you think about the system and how it works for a while you will understand what this does and why doing this will make the lift go higher when chambering shells.
After doing this there is no way a shell could drop or even shake around when chambering it, the lift pushes it to the roof quite tight until the bolt head catches it and starts pushing it in to the chamber.