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Finally ordered two gas check makers from Pat Marlins. My question is which material do you prefer for gas checks aluminium or copper and why?
The difference I see are the following:
Aluminum is cheaper easier to work.
Copper is stronger and more expensive.
Copper also is a better conductor of heat.
You asked that question at the right time. I have just finished doing a check on which is better and can honestly say I could find no winner accuracy wise, but Alluminium is cheaper and is easy to work so I will stay with it. Regards Stephen
Aluminum pop and beer cans are free, well sort of free, and aluminum flashing from the hardware store is not all that expensive. I woiuld use copper but it costs and my soda and beer can aluminum works just as good.
Take Care
Bob
Are aluminum checks made from beer and pop cans thick enough to be used on boolits designed for copper gas checks, or are they best used on plain base boolits?
I use them in both instances and they work just fine for all my 9MM and 38sp;/.357mag applications using PB and GC based lead bullets.
Take Care
Bob
Don't you double the beer can material for when used on a GC design bullet?
No I don't What would hold the two pieces together?Quote:
Originally Posted by Bazoo
Take Care
Bob
I do the math and work out which thickness I need for a given bullet and as it turns out my .460 projectiles for my 458 and 45/70 need checks made from aluminium spray deodorant cans all other projectiles will work with .012 Aluminium flashing which is cheap as chips. Regards Stephen
Beer can checks are used for plain base bullets only. Too thin to do anything with a gas check designed bullet.
zinc roof flashing from Lowes
Are you sure the flashing is 100% zinc. It could be steel electro plated with zinc.Quote:
Originally Posted by muskeg13
I've not done it, but seen where folks make checks out of doubled beer can material. Forming it together keeps it together.
They woek fine for me. What can they not do? I assume our beer cans are the same thickness as those in the US.Quote:
Originally Posted by tomme boy
Take Care
Bob
Beer cans here are .005 or so. Gas checks for handgun calibers are .010.
Same as ours. I have shot well over a thousand GC bullets used in my .357mag. They seem to swage on OK and do there job. I have never doubled up the disks. I use Pat Marlin dies.Quote:
Originally Posted by Bazoo
Take Care
Bpb
Gas checks I have measured are from 0.014" to 0.016" The ones I make are 0.014"
Let's use this bullet for example.
http://www.accuratemolds.com/bullet_...ullet=36-180LG
Bullet diameter is 0.358" The gas check shank size is 0.341" so 0.358"-0.341"= 0.017"
Here is another example. 0.310"-0.284"=0.024"
http://www.accuratemolds.com/bullet_...ullet=31-170JG
I don't see how a 0.005" gas check would fit and work for either.
I solve the questions by just buying quality commercial Hornady copper checks of the right size for my loads.
Problem solved. And I leave the cans for the recycle plant and the flashing for the roof.
Oddly enough they do. The Universe is not a constant and stranger things occur in the land of the mid-night sun.Quote:
Originally Posted by tomme boy
Take Care
Bob
I'm sure.Quote:
Originally Posted by GregLaROCHE
[I]Gibraltar Building Products Z Stop 0.21-ft W x 50-ft L 10.4-sq ft Silver Roll Roofing Item #435692Model #MB50
2-1/2 inches x 50 feet zinc strip roll offers a simple way to prevent roof build-up of moss, mildew and fungus
Made from 99% pure zinc. Suited for commercial and residential use
Even if the specs didn't state that it's nearly pure zinc, there's no way to mistake zinc for plated steel once you begin to work it. If anyone were still skeptical, they could always use a magnet. Steel would ruin your check making dies in short order.
Nice way to contaminate the lead on the range. If there is never a chance for the lead to be recovered then it might be a good choice to use the zinc. I find gas checks all the time e in my range lead I collect. I don't need anything else to worry about in the lead.
The minute quantity if zinc presented by gas checks isn't going to contaminate anything. Zinc is not kryptonite. A small amount of zinc is soluble in lead alloy and serves as a hardening agent. As mentioned in previous posts, zinc washers (which weigh a lot more than a gas check) were widely used in the 50s and 60s in some cast bullet designs, and I've never read anything to indicate they caused any problem with contaminating range lead. If you want to worry about something, worry about range lead contamination caused by the growing use of powder coated bullets.Quote:
Originally Posted by tomme boy
I reclaim my own lead in my berm. So yes it will make a difference. At a public range maybe not. A lot better choices out there.
As for that last line, "Copper also is a better conductor of heat."Quote:
Originally Posted by markmars
I'm not sure what the OP means by "conductor of heat", but I'm positive that when talking about a gas check, it's a non-issue.
The length of time heat is applied to the bullet base is extremely short. And while both materials will obviously conduct heat, the copper is denser than the aluminum (again, a total non-issue in that application).
So of the factors the OP lists, I think the last one is a total non-issue in that particular application.
Expense, ease of forming and maybe weight would be far more critical factors.
My understanding is on rifle bullets the base of a cast bullet will melt and leave lead in the barrel. So copper would cause ore heat on the base.Quote:
Originally Posted by Petrol & Powder
Your understanding is a bit flawed.Quote:
Originally Posted by markmars
The tiny fraction of a second that the bullet is in the bore and exposed to the hot expanding gases pushing on the base of the bullet is not enough to melt the lead at the base of the bullet. Gas cutting, is the culprit that causes leading.
Hot gases forcing their way around the bullet in the bore WILL result in leading. The GAS check is not a heat shield but rather a stronger metal that helps to seal the rear of the projectile against 50K + pressure and lots of heat. It only needs to do its job for a tiny fraction of a second.
NOW, this is not an absolute. There is undoubtedly a tremendous amount of heat at the base of the bullet but the length of time the bullet is subjected to that heat is not sufficient to allow the heat to overcome the mass of the bullet BUT hot gas leaking past the base will erode the lead.
The slight difference in mass of a copper gas check as compared to an aluminum gas check is not large enough to matter during that tiny fraction of a second worth of heating.
Thank you for the information. I'll make the gas check out of aluminum and save some bucks.
Quote:
Originally Posted by Petrol & Powder
I was going to try some of that stuff a few years back but the local hardware store stopped carrying it. Have you tested against aluminum and copper? I ask not so much about shooting but manufacture. Form easy, reject rate etc. I get about 1/300 AL that tear rather than fold, getting less so it was either something I was doing wrong or a bad batch.Quote:
Originally Posted by muskeg13
As far as berm pollution, I can always pull checks off with the same pliers I use to cut plated bullets, always got a few minutes before the pot melts.
powdered aluminium can be used as abrasive or polishing compound, therefore I can't think about sending alu in any form or speed down my gun barrels.
my OCD says no alu cleaning rods (do you remember old S&W revolver rods or K98 alu chain as part of their cleaning kit ?) and no alu gas checks in my reloading room.
I definitely have to agree with you on this !Quote:
Originally Posted by wilecoyote
Attachment 284470Quote:
Originally Posted by bangerjim
Guys: Where has gunsmithing metallurgy knowledge gone?
Aluminium oxide is the abrasive, not the aluminium; and the reason you shouldn't use aluminium rods is also the reason you shouldn't use brass rods -- grit (primer-glass-sand and dirt) which is abrasive gets embedded in the soft metal turning into a rattail file of sorts, and the grit is what then causes the damage. The soft metal in the rods IF TOTALLY CLEAN (as in only the first time it is poked in a barrel) cannot harm steel in any way.
Aluminum as a metal and the compound Aluminum Oxide which is used as an abrasive are two different animals when it comes to their physical properties. Try sharpening an axe using a beer can and let us know how it came out. I'm not a chemists by any means but combining elements into compounds can make drastic changes to them. A perfect example is Sodium Chloride (common salt) that you can't live without but each of the elements separately are extremely poisonous. And cleaning rods used properly should not contact the bore. How do explain steel cleaning rods being so popular if steel is so many times harder than aluminum. The issue with Aluminum rods has been explained as due to it's softness grit can be imbedded in the rod but again the rod shouldn't contact the bore.Quote:
Originally Posted by wilecoyote
notenoughguns I am mindful of the phrase" the blind leading the blind". Do either of you think the collective here who use GC's regularly would not have satisfied themselves years ago that aluminum gas checks work just as well as copper GC's with no impairment to our valued firearms. Many of my friends who were here when I first arrived are in heavens range now. The wealth of information that resides on this forum is immense. The information goes well beyond just personal opinion. Read, learn and contribute.
Take Care
Bob
I've made my own gas checks for several years using aluminum and have had no problems with them and don't worry about abrasion one bit. Come on guys, most all of us cast bullets out of some sort of reclaimed lead, wheel weights and such. If you're so worried about abrasion, you better buy your lead casting material from the site sponsor "Roto Metals" and be safe. The only time I buy commercial checks, Hornady and such, is when I get lazy and just don't want to go to the trouble of making them. Gp
NKVT,
... are my personal choices as admitted above. this knowing full well that I would probably be able to ruin an anvil with a rubber mallet.
I try to limit the consequences of murphy's law to my guns created by me for mishandling a rod or simply to save a dime. again, maybe am me_
I bet others are happy with different choices:drinks:: their guns, their choices.:drinks:
Because they don't bend and break as easily as the aluminum ones. Aluminum became popular BECAUSE of its softness and the idea that it would be less damaging to the muzzle crown of the firearm thereby preserving the crisp rifling at the muzzle. Since most nimrods shove and unprotected cleaning rod with a steel cleaning tool attached directly into the muzzle and then work the rod in and out and in and out 500 million times while drawing it against the crown rifling, they abraded away the crisp rifling. Manufacturers marketed aluminum rods to delay muzzle crown abrasion and because they were lighter (and cheaper to produce) for the sportsman.Quote:
Originally Posted by NEKVT
Experienced shooters clean from the breech end whenever possible. When forced to clean from the muzzle end, a muzzle protection device is placed on the cleaning rod to prevent muzzle abrasion. My rods are made of aluminum, steel, and plexiglass. All are used depending on the firearm. My 1861 Springfield is loaded with a steel rod and I cringe every time I run it into the bore in an authentic loading sequence. I can hear the steel on steel SCREECHING in my ears.
Anyway - that's why aluminum rods came onto the scene. Use any material, just protect your muzzle crown.
It's funny how we remember things differently. Go back to the times when Townsend Whelan was a popular gun writer and what did we see? Brass and aluminium rods were popular because they were CHEAP while steel rods were expensive. Every-day wags and hunters thought cheap was ok while people that were concerned with rifle ACCURACY uniformly recommended steel as the rod material, precisely because grit did not embed in it and damage the crown or the bore (and non-embedding coated rods like Dewey did not yet exist). I don't believe there is a bench-rest or long-range competition shooter out there that wouldn't assault you if you tried running a soft-metal rod down the bore of one of their rifles.
Not all aluminum works for GC Just like not all copper works for GC
copper needs to be 99% pure/dead soft. I get mine from riogrande (a jewelry making supplier)
Truth! I think it's a matter of when we became active shooters, what we have read over the years, what we retained from all that reading, and what we have personally tried. It's all good.Quote:
Originally Posted by oldcanadice