All of you guys have brought up a lot of good points. And I appreciate them. However, when I put on the bases, they were weaver brand bases, not cheap tasco type bases. The screws measured at right near bottoming out in the screw holes in the barrel. I know because I measured them. When I put on the epoxy, I used a minimal amount, and did not put any near the screw holes, and there was no epoxy in the screw holes after the mount came off. I used blue lock tight on the screws, tightened them evenly, and even used a small brass hammer to "set " each screw so that the threads on the screws mated with the threads in the barrel. I did it exactly as Bob Milek did it in his article in Guns and Ammo magazine on mounting scopes on T/C barrels. Being that I used lock tight on the cleaned threads, I seriously doubt that the screws came loose, causing the mount to come off. The scope was mounted as far back as I could get it, to get the most support from the 4 factory screws as I could get. Everything worked fine with the lighter 2X scope, but the much heavier and longer Burris 1.5-4X scope apparently was too much weight for the type of recoil the .35 Rem has.
The barrell was a used one, like new, when I bought it at a gun show quite a few years ago. The only thing I can think of that may have contributed to what happend was that the previous owner may have used too much force on the scope mounting screws and partially stripped the screws before I purchased the barrel. But as I remember, the screw holes looked ok when I mounted the scope, but who knows, it was a long time ago.
Anyway, my question was, "has this happened to anyone else just using the 4 factory holes on the .35 Rem. super 14 factory barrel"? I know now that at some point, I should have sent the bbl in to SKS or E. Arthur Brown for the 6 hole mount and beefier scope rings. But, when things are working I tend to not worry about it, especially when Bob Milek said it works. If it wasn't for him, I would never have bought a Contender in the first place. Sure do miss that guy.