drum turns stiff

Alrighty then, I'll disassemble everything and start over. I've done a ton of brakes over the years, it's gotta be something simple I'm doing/not doing. One thing that does puzzle me though...on this car, the shoes are held to the backing plate with cone shaped springs that go through the shoe. So why was this lone stud, obviously from a different car, in the drum? When I pulled the drum off and disassembled the brakes, this was on the floor with the springs and other parts. Here's a pic of the drum and brake assembly.

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