Hi,
Wolfie, I tried and tried, but couldn't get a shell to stick in the mag tube of my 870 the way I think yours did. When you took all the innards out, was there a magazine follower cup in there? Something like this, only probably black:
http://www.brownells.com/shotgun-parts/magazine-tube-parts/magazine-followers/remington-1100-11-87-versamax-magazine-follower-12-ga--prod10930.aspx
When assembling all the mag tube bits, it goes in first, solid end contacts the shell, spring and plug kinda slip into the open end. That piece probably has multiple purposes, but the most important one looks to me to keep everything centered up in the tube without binding. Without it, I'm wondering if the spring and plug were wiggling around in there and caused the jam.
Now, I could jam the gun just fine when 1 1/2 shells tried to occupy only one shell's space as the regular shell was followed by the backwards one, but all it took was removing the trigger ass'y to easily clear things. I take a cleaning kit with me on all my hunts, and there are a couple of small brass punches in there to get the trigger pins out. If I forget them, there's also a small Phillips screwdriver to do the job. And if that gets lost or forgotten, last but not least are two appropriately sized nails with the points filed off a bit (yep, belt, suspenders AND a drawstring!) Even without vise grips there's something around to smack 'em with...
BTW, was that a typo, or did you guys pull a fast one on Sammy and tell him he could only get 10 birds? Limit's 15 here, max 10 whitewings, and I thought they'd made it the same statewide a couple of years back. And of course the limit on Eurasians is "how much ammo did you bring?"--nationwide, I think!
And for the guys wondering how you load 'em backwards, just shove the brass end in first! Super simple to do, but depending on the technique used to get 'em out, 'tis either simple or an event to be recalled in story and legend to undo. Methinks Wolfie's experience will live on as an epic!
Rick C