Hey folks,
I started using copper gas checks 50 years ago when they were cheap as dirt. As years went by, gas checks went up in price until they were quite a significant cost to me.
About five or six years ago, I heard about making my own aluminum gas checks from soda cans with a FreeChex tool kit sold by a fellow named Charlie Darnall out in California. Considering the price of copper gas checks, I bought one of the FreeChex kits to see how they worked and how the aluminum gas checks worked. I got a tool set for 38 caliber, started making gas checks for my .357, and found out they worked just fine.
The first version of the FreeChex used a punch to punch out aluminum discs from a soda can, and then a mandril and die to form the gas check from the disc. It was time consuming but I could do it while watching TV in my recliner. Then Charley came out with his FreeChex II tool set. It was a little more expensive but cut the discs without having to use the punch and was a little bit faster. I ended up with two of the original FreeChex tool sets for two calibers (.357 and .30) and two of the FreeChex II tool sets for two other calibers (.44 and .45-70), and I still use both types of sets to make my aluminum gas checks. Later, Charlie came out with his Freechex III tool set that works with a cheap arbor press and makes checks faster than you can believe. Each cycle of the handle makes a finished check in one step that falls through the bottom to a collection pan. I never tried the FreeChex III, but I saw it work on a You Tube thing where a fellow is feeding the machine from a continuous coil stock. You simply cannot believe how fast it works.
The FreeChex III is to be use with either copper or aluminum thicker coil stock you can get at Home Depot rather than using aluminum soda cans. I already had tool sets for the four calibers I use, so I never tried the FreeChex III tool set. I also liked the idea of using scrap soda cans for my gas checks.
And in case you are wondering, no, aluminum gas checks do not form aluminum oxide and ruin my barrels. The aluminum is coated on both sides, and when placed on the bullet which is sized and lubricated, they are well lubricated and not about to oxidize.
Best wishes,
Dave Wile