Gas check material thickness

[xs11jack]

I have a buddy that drinks a lot of beer and has given me a lot of empties. I measured them and they come out at .005 inch. Is this too thin? I see most people using .010 and thicker.
Ole Jack

[gpidaho]

Good for plain base checks and have been used folded over a time or two by some for standard checks although that didn't work well for me. Gp

[Larry Gibson]

For 30, 31 & 8 mms GCs I use .012 brass or .014 aluminum on GC bullets.

[dg31872]

Larry, I am just getting into making checks and have a couple of questions. Why different thicknesses for different metals, and two, do you prefer brass/copper to aluminum, or are they equal in performance in your opinion?

[Jniedbalski]

I would like to know the same thing. Is allunium as good as copper for checks?

[Retumbo]

Aluminum is the only thing I use

[dragon813gt]

Good for plain base checks. You can try folding it over, doubling them up, but I wouldn’t expect great performance.

[codarnall]

I had on good authority that some metals were better performers than other especially where accuracy was a primary consideration. Cu and Brass generally out performed aluminum (Al). the tool design does not work well with really thin soft copper because it does not allow smooth shearing w/o tearing. So .007" was deemed minimum forth 224 family. Coiland foil came to my rescue with high performance Al in specs and thickness. So my tools then worked worked much better (FreeChex). So a whole range of thickness allows the caster to best fit the shank. .007 for .22 and .023 for the fifties. Polymer coated castings in my opinion are very promising in my high velocity tests to 300 Yds.

Charlie

[Tom W.]

I have a Freechex II for a .45 cal. handgun, but I also have a .44 Mag revolver. I have taken the beer or soda cans and cut strips wide enough to be folded over, and pressed them flat w/ my HF arbor press. I'll then punch the checks out and get good usable gas checks.
One day I got a wild hair and decided to take some checks and put them on some of my .44 boolits. Into the LAM-II they went on a Lee 310 gr. and believe it or not came out just fine, and worked like they were store bought.
Just an aside in case anyone is considering it.....

[Larry Gibson]

Larry, I am just getting into making checks and have a couple of questions. Why different thicknesses for different metals, and two, do you prefer brass/copper to aluminum, or are they equal in performance in your opinion?

I use the .012 thick brass because it is easier to work with with the GC makers mentioned I use (not Pat's). It's easier to cut into strips with a paper cutter and give almost no rejects when forming the GCs. It also works as well as Hornady GCs on loads up through 2400 fps. The .014 Aluminum cuts into strips and forms GCs ok. I prefer the Brass GCs as I don't anneal either and they hold up better under the higher psi's of HV loads. The aluminum appear to split where the rifling creases them and come off on muzzle exit resulting in flyers on target. They also tear up my chronograph screens. I do use a lot of the aluminum GCs on handgun and "normal" velocity rifle loads w/0 problems. I do not seat them below the case neck for the usual cautionary reason.

[dg31872]

Thanks Larry. Much obliged.

[Dragonheart]

If you are just getting into making gas checks I would suggest start off by getting your material from Coil & Foil and save a lot of frustration. You can use aluminum roof flashing of the proper thickness, but it needs to be annealed (softened) to work properly. Aluminum seems to work just fine especially when combined with powder coat. Copper is a more expensive alternative and I don't see that it is needed. Proper fit, squaring the check and a perfectly flat bottom are the keys to success, not the check material.
If you haven't seen Coil & Foil material or a FreeChex in operation check out this video:https://youtu.be/R5sIuzphTEk