Having a tough time seeing any difference! Let's make sure we are clear on the procedure. I am going to go through everything in simple terms as I am not sure how up you are on the M1's manual of arms. I a not trying to belittle you in any way or insult you abilities!!! :-)
First, EMPTY the gun (you'll load it in a second, so make DAMN sure you are in a safe zone and DON'T TOUCH THE TRIGGER and MAKE SURE THE SAFETY IS ON!!!)
Pull back bolt but DON'T LOAD A ROUND as you usually would. Drop the BOLT release (the button on the right of the reciever). Now, load the tube to capacity. Pull the bolt back BUT NOT ALL THE WAY. IF you pull it back all the way, the shell carrier will try to pop up with the slightest forward movement of the bolt.
Carefully place a shell down into the carrier through the ejection port- you'll have to put in in slightly brass first, because the bolt will be over the back end of the shell. Finally, put another shell where you would normally in the chamber and SLOWLY let the bolt move forward.
The goal is to catch the lower shell up under the bolt and chamber the top shell. The shell on the carrier will prevent the hammer fall from tripping the mag release (the tab above the trigger finger) when fired so as soon as the bolt cycles back and begins it's return stroke, the carrier will rise and feed the lower shell.
Now there will be no shell in the carrier so when you fire it again, so the hammer fall will trip the mag release and a shell will pop into the carrier to be chambered on the next return stroke of the bolt and simultaneously (more or less) reset the mag release to cut off the mag agian until the next cycle.
Potential screw up #1:
Loading the chamber and the mag as usual and hitting the mag release to pop a shell into the carrier. This should give you a chambered round with the next round already in the carrier, but you won't have a full tube.
Potential screw up #2:
Cylcle the bolt back and hit the bolt release. Then, hitting the mag release. This will lock the shell carrier in the down position and prevent loading rounds in the tube. You can hit the bolt release to unlock the shell carrier.
Try the above procedure and let me know if it works for you. If so, then we're done and you're happy. If not, then get me a top down pic of the carrier and a pic looking up into the loading well with the trigger group in place (I'm trying to see what your bolt release bar looks like in the receiver).