Which do you prefer? Sage has copper at .017" and aluminum at .015" for 30 caliber. (not gator checks) Does thickness play a roll in your preference?
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Which do you prefer? Sage has copper at .017" and aluminum at .015" for 30 caliber. (not gator checks) Does thickness play a roll in your preference?
What few gas checks I use, I just buy a box of Hornady's.
Until you get up into or past the mid-teens in speed, you can do OK without them.
If I used more, I'd probably make them. For me, I don't use enough to justify getting set up for that.
Copper better. Thicker better.
But your loads might not need better. Then cheaper is better.
But $5/k is barely cheaper. I would only choose aluminum if my bullet shanks are too fat for normal checks to crimp consistently. Or if the price were way more different than $5/k.
For years and years I have always used the Copper gas checks from Hornady. I bought up a ton of the various checks I needed before all the shortages began to happen. Hopefully I can get by for at least a few more years. If not, I may need to look into a check maker.
Is there any concern about aluminum in the bore? Aluminum is quite the abrasive. I know there is not much of a bearing surface but it's still there.
I have used several thousands of both over the years and really can not tell any difference in performance.
Supposedly the al check has no elasticity and will not grip the base. I just went to double powder coating over 2k fps and changed to all plain base bullets and stopped using GCs entirely.
Never found aluminum to be abrasive. I make my own gas checks from aluminum and they do not seem to be at all abrasive!
Many abrasives have aluminum in them. Ever see the term "aluminum oxide"? But with a gas check, there is hardly any bearing surface that could cause wear.
As far as the elasticity of aluminum, that may be true. But, copper can be the same way if it is not annealed properly. Several have written they anneal gas checks to make them dead soft, the same reason you anneal case necks so they won't crack or if you are manipulating the case for a wildcat.
I've used both copper and aluminum and I see no difference. On the aluminum gas checks I usually powder coat after crimping the checks on. I don't think about the aluminum checks being abrasive, it's just easier to install the checks before the powder coat. After coating there would be no issue even if the aluminum were abrasive. I haven't seen any problems with either type of gas check.
I am not going to live long enough to wear out my bore with aluminum gas checks.
I can and do make my own aluminum [.014/.015 aluminum flashing and .004/.008 pop/beer can/bottle] and brass [.012 or .014] GCs in .22, .30/.31, 8mm, .35 and .45 calibers. I've found they are very adequate for most of my cast bullet shooting. They perform well, perhaps as well, as commercial GCs below 2000 fps. Above 2000 fps they do not perform well. The aluminum .014 GCs I make are most often used for handgun bullets usually upwards of 1200 fps and rifle plinking/casual shooting bullets upwards of 1900 fps. The 45 cal .004/.008 pop/beer can/bottle GCs are for use on PB cast bullets although the .008 GCs seem to work well on GC 45-70 bullets.
I use lubed bullets on which the bullet/GCs will ride a layer of lube in the barrel, thus no worries about any abrasion if there is any.
My preference for best accuracy with rifle bullets is Hornady or, now Lyman, crimp on GCs. I also stockpiled quite a few and have enough for most of my future use. Of my own make my .30 cal brass GCs perform very well up through 2500 fps and give the same accuracy as the Hornady/Lyman crimp ons. The Hornady crimp ons have proven excellent up through 3,000 fps.
Of the other caliber cartridges I shoot cast bullets in I don't really shoot enough cast to make the cost of a GC make worth it. A box of 1K GCs will last a long time with those cartridges. I wouldn't hesitate to use .014/.015 aluminum GCs for those as they all are shot at less than 2000 fps.
I make my own aluminum gas checks. I tested them along side Hornady checks and the accuracy was the same and often the aluminum beat them. I use different thicknesses of aluminum for different caliber, with the thickness increasing as the caliber gets larger. Unlike Larry my aluminum checks will perform right along Hornadys to even high velocity. I've also recovered many bullets and the checks are still on them. I don't think the aluminum is going to wear the bore any and I believe many come to that conclusion that aluminum oxide is used for an abrasive. When we use aluminum it's shiney and new, plus as Larry mentioned we have lube on our bullets.
This will probably raise the hackles on some, but don't leave out zinc. I make my own checks in .22, .264, .30, .32/8mm, .348, .358, .40 and .45 using Freechex and PatMarlin tools. I began using copper sheets PatMarlin sold years ago and aluminum scrap and flashing, but tried zinc roof flashing left over from an anti-moss project with good results. I don't think the check source material matters much for handgun applications or lower velocity rifle loads, but I reserve the copper checks for use in rifle loads approaching or exceeding 2000 fps.
I've never had a problem with loose copper checks, either home-made or store bought, but need to be careful with thickness and shank dimensions with aluminum. My aluminum checks don't form as pretty as the copper ones that look a nice as Hornady or Lyman checks. I lucked out with the zinc flashing being the right thickness, and being rather soft, they fit the shanks well.
Copper, aluminum, and zinc all share a common trait. They're all excellent conductors of heat.
By weight: copper > aluminum > zinc.
By thickness of the check (factoring in the density of each metal): copper > zinc > aluminum.
I use mostly copper checks.. but use both copper and aluminum on 45-70 and see 0 difference in them.. the aluminum grip just fine too. As for aluminum being abrasive.. what about the old silver tip ammo.. never heard any warnings about it?
Let me say this first: Zinc is a lustrous bluish-white metal. It is found in group IIb of the periodic table. It is brittle and crystalline at ordinary temperatures, but it becomes ductile and malleable when heated between 110°C and 150°C.
Are you sure that zinc flashing is pure zinc? I'm not condoning you using it, just that it doesn't act like pure zinc when you can form it into gas checks. Am I missing something?
I didn't say ballistic silver tip..the new stuff they sold..but the old semi original..ie.. Aluminum jacketed stuff..which later became nickel plated copper. Ps..the aluminum was circa 1974.
The new polymer tipped one's are just nosler's. And nothing like the original.
Previous to 74 the silver jacket was an alloy of copper, nickel and zinc. At one point some were tin plated too.
I would have zero concern about aluminum as far as bore wear, it's not going to hurt a thing.
My opinion on gas checks is the biggest cost is time. You easily double or triple the time it takes to size bullets with gas checks vs plain base. That's if things are perfectly sized. If you have bigger shanks, or your powder coating is a little too thick, then that takes time to figure out too. With that kind of time invested, does $23 vs $28 per 1000 really matter? Is anyone shooting multiple thousand gas checked bullets a month?
Copper is a superior material for a gas check plain and simple. Aluminum must work fine for some people, but if you are pushing the limits, you are just shorting yourself if you aren't using copper. I only use copper myself, and I also anneal my gas checks. It makes a big difference on a variety of bullets when you aren't fighting springback.
My opinion on aluminum for gas checks is that they are best for playing base bullets and if your bullet actually has a gas check shank probably copper is ideal.
Another reason why I think aluminum would be fine as a jacket material is remember some bullets use mild steel as a jacket.
Yes, I guess you are missing something. This product is 99% zinc and is very ductile and malleable at normal interior and exterior temperatures. It handles just like aluminum flashing and is promoted to kill and prevent moss growth on roofs. It works great for that use as well as for making gas checks.Attachment 312912
Thanks for that reply. I've not seen the stuff and would like to get my hands on some. Normally zinc is very brittle, thinks the old carbs that were made from it and matchbox cars. Very hard stuff. I thought what you got was zinc coated not pure all the way through.
Maybe it's annealed in the manufacturing process to maintain it's softness? I think the exterior coating some thick coated galvanized steel also seems soft. I believe that process calls for steel to be dipped in molten zinc.
Anyway, the zinc washer bullet bases of the '50s that were the forerunners of modern gas checks had to be soft but tough enough to protect rifle and pistol bores.
"Modern" copper GCs were in use a long time before the '50s. It was the lubes of the time that were the real culprits causing leading. With the advent of "modern" lubes such as the NRA 50/50 formula that negated any advantage the zinc washers provided to prevent leading.
Here's a good read when copper gas checks were first used:
https://castboolits.gunloads.com/arc...hp/t-2347.html
Have used both and only issue with Al was many did not stay on the bullet, would find 10-20% on the ground 25-75 feet in front of the rifle. Whether this was the difference in thickness of the Al, GC shank diameter, or other factor I don't know. Copper checks, either Hornady or Gator checks, did not leave a trail of checks to the target. Crimp-on type checks stayed on, but the Lyman checks did sometimes come off and would be found on the ground, but very very few. Again whether this was the fault of the check or caused by the GC shank size I have no idea. Given the cost difference I use crimp on types and before the panic started had purchased enough to last til my shooting days are done.
Very toxic might be too strong a term. Harmful is probably a better way to put it. The chances of getting seriously sick or dying from welding galvanized steel are almost nil. Apparently if you breath enough of the fumes you get flu like symptoms. I suppose if you did it daily for years on end you are probably going to end up with health problems, same as running too light a shade will burn our your eyes. Basically all you need to be safe welding galvanized is to have good ventilation. Stick welding is a very good choice, and blow a fan while you do it.
Long story short, no, zinc gas checks are not a health concern.
Well that's a relief to hear; I had unknowingly used some scrap galvanized pipe to practice with my Harbor-Freight welder (I had zero experience or knowledge), and he assured me that I had certainly caused myself harm. Seemed to think that I would eventually develop neurological problems from it.
Yeah you would have known it if you would have been affected by welding the galvanized most people just burn it off with a torch or if stick welding use a little bit of a fan or you just don't breathe the fumes I know a guy that got sick from welding galvanized and they just told him to go home and drink a lot of milk he was good the next day
Father in law had a man come to his farm to weld galvanized metal in a confined space that got sick, went home and died. My Dad was a journeyman welder. I was very cautious with galvanized metal.
Zink Gas Checks. Can't see that being a problem.
I prefer Sages gas checks, great quality and much cheaper than "name brand." I've used bot aluminum and copper and really never noticed aby difference.
"I've used both aluminum and copper and really never noticed any difference."
- say a lot of shooters
A lot of calibers, there probably isn't any functional difference when using common powders and loads. Some cartridges might just be slightly over the edge where you have to use a check, at all. You don't need much check to reach full power in cartridges that are rated at less than say 35k psi to begin with.
Some calibers might have a variety of cartridges in that caliber, and the full thickness copper check might only be needed for max cast velocity in the higher pressure of those cartridges.
It's completely unsurprising that a lot of people have found no difference between copper and aluminum. But I'd be surprised if someone with the hobby of pushing boolit velocity to the absolute max wouldn't find a difference in some calibers. Because copper is expensive. Manufacturers save money by making steel and aluminum cases, and those ARE inferior (to us, at least). Why wouldn't they save money by making aluminum gas checks if it never made any difference, at all?
Also, the density difference might affect longrange accuracy or ballistic coefficient in specific bullets.
"But I'd be surprised if someone with the hobby of pushing boolit velocity to the absolute max wouldn't find a difference in some calibers."
Yes, the difference is there......
Think of the gas check as a gasket. Even a paper gasket, when supported, is very strong. A gas check is supported by the base of the bullet. There's not going to be very much difference between if the check is aluminum or copper. How about the people that anneal their copper checks, wouldn't that make them more weak? If this doesn't convince you how about paper patched bullets? Those can be shot to very high pressures and velocities and survive........ with accuracy I might add.