I bought a used Redding Classic Model Powder measure. It was jammed/clogged when I bought it, so I took it apart, except for the metering chamber. I don't want to ruin it. Who can tell me how the metering chamber comes out? Does it come out into the powder reservoir or out the front? Is it threaded? Left-hand threaded for some reason?

there is a set screw that is on the handle side of the drum, loosen or remove the set screw and the knurled thumb screw on the other side of the drum and the metering chamber should slide out of the drum to the front.