About FreeChex

In 2006, when the price of copper was skyrocketing, Charlie Darnall wondered if discarded beverage cans could be a source of metal for home made (free) gas checks. He knew other hobbyist reloaders were complaining about the cost of commercial gas checks. Rare sizes, such as 41 caliber, were unobtainable from commercial vendors. FreeChex do-it-yourself (DIY) gas check tool was an idea whose time had come.

FreeChex [b] in its original form, had a punch for cutting metal discs (from aluminum cans), a forming anvil, and a mandrel that fit inside the anvil. Users had to provide their own leather mallet and a firm cutting surface (such as lead ingot) to cut blank metal discs from aluminum-can stock.

Two years later, Charlie Darnall decided to eliminate the cutting tool because low-cost cutters were unreliable and high-quality tools were prohibitively expensive.

Freechex™ II solved alignment and cutting issues. Charlie Darnall designed a dual action cutter-guide that features a crisp shearing edge in the middle of the die. [e] The cutter-guide is able to shear discs from strips of metal stock, and it has a second function of aligning the mandrel while the gas check is formed. The anvil [d] component has three functions: securing the metal stock, acting as a shearing surface, and providing the mold cavity where the disc is formed. The anvil was designed with a 0.40 mm slot through the bore; this slot secures the metal strip while the user applies shearing force. A leather mallet (provided by the user) can apply sufficent force to cut almost any kind of metal stock but some reloaders prefer using a mechanical press to have better control. After the shearing operation is completed, the cutter-guide acts as a precision guide for the mandrel. [g] When the mandrel is tapped through the cutter-guide, the metal disc is pressed into final shape. Finished gas checks are passed through and out the bottom of the anvil. [h]

Freechex™ III [i] was specially designed for reloaders who wanted to make large quantities of gas checks, quickly, with a hand operated press. Metal stock is advanced by hand and individual gas checks are cut and formed with a single stroke. The mandrel and anvil are a single unit. [j] The mandrel component is force fit through the base of the anvil. When the hollow disc-cutter is pushed downward it cuts the metal disc. Pushing the disc-cutter further down the cylinder causes the disc to swage over the mandrel tip where the gas check is formed inside the disc-cutter tube. Freechex™ III includes a coil spring to bring the hollow disc-cutter back to the starting position. Finished checks can accumulate inside the disc-cutter tube or, if the tool is mounted upside down, discs can fall out the bottom of the disc-cutter into a bin provided by the user.