Resurrecting this old thread . . .
The gun in question (shown in the original photos, which are no longer accessible due to me walking away from my Photobucket account many years ago) was sent to Gunter Pfrommer for repair of the cocking sear of the lower barrel.
Gunter tore the gun down and noticed the hooks. He said those hooks are an extra safety feature added to some Winchester 101s. The feature is to prevent the gun from firing when the barrels are pointing down. The idea being to keep one from shooting off his own foot.
After over 17 years we finally have the answer to the question.
—Shinbone
