Abstract: An improved chemical feeder employing periodic partial immersion in a forced circulation system is provided having a soluble chemical hopper, and a dissolving chamber into which the soluble chemical chamber extends an adjustable distance and a discharge chamber in fluid flow communication with the dissolving chamber to selectively receive chemically treated water from the dissolving chamber and discharge it into a flow loop connected to the forced circulation system. A visual indicator ring is preferably present to show the height of the hopper. The adjustable hopper allows an expanded range of chemical feed rates for the feeder.

Abstract: A dual plastic compression formed shotshell casing includes an injection-molded annular-shaped hard plastic rim and an elongated compression-formed tubular body having an integral basewad portion at its base end which is mechanically interlocked with the rim to define the final basewad of the shotshell casing. In method of making the shotshell casing, the hard plastic rim is first injection molded independently. The tubular body is then formed in a two-step process. In the first step, a plastic preform is injection molded over the rim in mechanically interlocked relation to the rim. In the second step, the tubular body is compression formed from the preform mechanically locked to the rim.