Home grown gaschecks.

[lreed]

Hello; I've been tinkering with a gascheck forming tool that seems to work fair-to-middlin' well,the punch out a slug and "push it thru a die" kind. The cal is 8mm as that was what I was playing with at the time.The slug was cut from an aluminum food can .010 thick,as just a trial, worked well,the check clings tight to bullet after going through a.325 lube-sizer die, can't remove it without a tool. The food can supply of metal was very soon exhausted,found some aluminum flashing that was the required thickness, it also formed acceptable checks.
Sounds good,so far,thought I'd try to switch from aluminum to copper,I had no soft copper stock, so I split some copper tubing annealing and hammering til I got my required stock, this'' ain't no option'', however it did make a few nice checks. I started a search for copper stock of the right sort, got a real eye-opener; as best I can figure it would probably cost me money just to make copper checks over buying ready made!!!Soooo- aluminum appears to be the only option for cheap gas-checks.
After all this blather-I'll get to what"I'd shore lak to know", is the abrasiveness of aluminum gaschecks sufficent to exclude them from use in valued firearms????I think I've seen aluminum jacketed pistol bullets [Blazer],but have not seen or heard of commercialy produced checks. I'm as usual, trying to do 'stuff' that requires help from people who are more knowledgeable than myself and to whom I'm always grateful for replies and advice. Thanks lreed

[Junior1942]

When aluminum rusts it makes aluminum oxide which is almost as hard as diamonds. That's why aluminum cleaning rods wear out rifle bores if used from the muzzle. But an aluminum gas check is (1) painted; and (2) coated with lube so it shouldn't rust. So shoot to your hearts content.

Is this one of those eBay Charlie Darnell kits?

[Le Loup Solitaire]

In reading the posts that have shown up from time to time on making gas checks from aluminum, two issues are of concern and get pointed out. One is the fact that aluminum oxidizes and since aluminum oxide works well as an abrasive in the manufacture of sandpaper and grinding wheels, what will it do to a gun barrel? So some say its all a real bad idea, others say the amount of surface contact is not a big deal, and yet another opinion is that if you keep the gas checks in a little jar and away from air-then there is not much, if any, oxidation. the second issue is that the thickness of the aluminum that is used to make beverage cans is too thin. So aluminum flashing of a greater thickness has been tried and of course it works. Copper sheeting usually used for craft work has been tried, but I don't know the thickness or the cost. It has got to be better than the current price of gas checks sold by Lyman or Hornady. There are forum members who are wizards as machinists and talented lathe operaters and sooner or later someone is going to come up with the answer, at least for a die and punch that mounts in a loading press and can solve at least that part of the problem. And other members who know about metals and their properties can hopefully fill the gap on the oxide factor of aluminum and/or alternatives for choices of metals. It may take a lot of posts, but it'll be worth it. In the meantime it sounds like you have done a good job in taking on the problem with your 8mm. Good shooting. LLS

[felix]

As your pour fluxed aluminum, it rusts before it hits the mold. In other words, it is always rusted. ... felix

[DeanoBeanCounter]

One source of sheet metal might be a metal or specialty metal supply company. I used to work at one and they always had lots of scrap of all sizes.
Dean

[Pepe Ray]

or anyone more knowledgeable than I.
Doesn't electrolysis take place between dis-similar metals if they are good conductors?
Pepe Ray

[badgeredd]

Just had a thought (boy was it lonely!), why wouldn't brass shim stock work. One can buy it in various thicknesses and it would be close to the properties of copper. Gotta be cheaper than pure copper. Guess I'll look it up and see how much .010" shim stock is!

[felix]

Yes, PepeRay! In the books it is called a galvanizing current. The problem will not be severe enough to worry about with the lube in place. It will occur, but slowly. About like loaded ammo welding in a small town policeman's 38 special cylinder that has never been out of the holster unless used to kill a dog/cat run over by a car. How often does that happen? Once in 25 years according to my old town cop. ... felix

[castalott]

If you use too thin alum. for checks, run medium hot loads. Every one I have recovered has expanded out to groove diameter. That 'big light' behind the bullet has lots of energy available to force the check and bullet base out to groove diameter if you use the correct load.

If you can find food cans lined with 'teflon', you can cut the check so the teflon is on the outside. That works ok too....

[imashooter2]

I've seen ground straps that were many sheets of .010 copper fastened together on the ends so as to remain flexible (kind of like stranded wire). You might try scrap yards looking for some.

[floodgate]

On the aluminum oxide abrasion question, another take is that Al2O3, with other trace chemicals, is sapphire, and sapphires have been used as a wear-forever bearing material in clock and watch movements. The oxidation occurs almost immediately when fresh aluminum is exposed to air, and on a smooth surface like rolled or extruded aluminum it should be smooth and make a fair bearing surface. The Al2O3 abrasives are fractured and sieved "sapphire" crystals, and work quite differently. As to muzzle and barrel wear from Aluminum cleaning rods, I believe that this is due primarily to grit embedded in the relatively soft metal of the rods, and not to the metal or its oxide.

I'd not worry about the use of aluminum gas checks, EXCEPT insofar as the casting of boolits from Al-contaminated range scrap seems to yield problems similar to those seen in zinc- or copper- contaminated alloys.

But then, I don't pretend to be a metallurgist; Grumpy One, do you have any input on this issue?

floodgate

[castalott]

There is one bullet with a copper Hornady check and 3 with homemade checks...

[lreed]

Thanks for the replies,...to Jr The food cans I made mention of were coated,treated with something that did appear to limit oxidation,gold-brassy look,if a supply of this material could be obtained it might be the ticket, the flashing was just plain stuff, not even very shiney.The lube part I've thought on quite a bit,when you consider most engines have aluminum pistons and some even have aluminum cylinder walls,and they make millions of cycles. The check making die is of my work.
To Badgeredd..there are so many mixes of brass some very brittle and all brass I've dealt with is tough to cut with a punch,I've even explored the possibility of zinc foil, but that stuff they say will spontainusly ignite.
Castalott...great looking checks, What material,calibre and tool used if you would?
Thanks lreed

[castalott]

Hi Ireed!

The caliber is 30....the bullets are 311332's and 311041. The check material is the aluminum sheet used in the printing industry to make newspapers. I got a lifetime supply years and years ago which is good because they won't sell it to you anymore. Something about chemicals used with it now....A 2 foot by 3 foot sheet was $0.50 twenty years ago. It is a little thin but but works ok with full power loads. I've never tried reduced loads with it.

I have some that was used for a solar collector and was painted. I wonder if the painted side could be turned in to make the check thicker?

The tooling is homemade and actually quite ugly. There is a simple tool to make discs, a simple tool to form checks from the discs, and a simple tool to squeeze them on the bullet shanks without sizing the bullets.

I've posted it all here before with several piks. Maybe you can find it in a search....If not...send a private message & I'll send you all the info I have.

[looseprojectile]

I spent some of my youth as a precision sheet metal bench mechanic. The making of these tools to form cups is what we called shop aids. Fairly simple. Need to figure clearances and such for punches and dies. Many times a stock size punch can be used to make the blank. An old Wales Strippit fabricator machine would be useful. Punch and form in one shot like a machinegun. Would work in a loading press, though much slower.
I see no reason to not use SOFT STEEL for checks. It would seem that steel would be easier to find and less expensive. Lots of full length steel gas checks are used by the militaries of the world.
I will still buy my gas checks as long as I can get them. I just paid more than a nickel a piece for .50 caliber checks, nearly my limit!
Life is good

[leftiye]

How about a coating that we could spray and bake on (I've seen some teflon refinishes like that) the finished checks? Sounds like we aren't too far from taking the ridiculous cost out of checks. Almost all of the basic materials (and just about everything else) has risen to prohibitive levels (copper, brass, tool steel, etc.) when one wants to buy it in small end user type of purchases. Pure greed on the part of the economy dealing with the public I say. Don't we the people already support half of the earth? Biggest milk cow there is!

[porkchop bob]

Soft drink and beer alum cans have a protective coating on the inside. Palce the coated side on the outside of the GC. In fact all alum cans used to contain food are so coated. The road sides are littered with them. Where I live the trash cans at the beach access are over-flowing with alum cans.
Bob

[PatMarlin]

This may be a bit soon to announce this but I have a friend who is a fine machinist, that is going to offer a neat 2 peice gascheck maker tool for sale, that does not require a press.

It will be available for all calibers, and work with .010 copper, or alum beer can material. Beer cans are about .005, so you could use 2 per boolit, but some folks may even like to use just one.

He may even offer custom sizes. Most likely we'll run group buys per caliber when everthing is tried and true.

[bruce drake]

Pat,

Could you PM on the contact information for your friend and when you plan to come up on the Group Buy board. 30 cal to start.

Bruce

[DonH]

Could someone post pics of the tools sold on ebay? My shooting is of necessity a low buck operation. If I can give a friend something to look at, maybe he will make it for me.