DIY gas checks





echo1er

uber Member
#1
I have googled and I have YouTube. DIY gas checks. Now I wanna try making my own gas check tools punch and so on. Has anyone ever made there own gas check tools
 
#2
Negative, I do not have access to machine-shop nor experience as a machinist. I do use bullet swaging dies to fabricate projectiles. The manufacturer (Corbins) that I use, sells kits to make gas checks. You would be replicating that capability to punch out a specific sized circle of flat copper, then a separate die to create the cup.

If you make this, would be nice to see you post your results (especially photos). Good luck.
 

echo1er

uber Member
#3
Negative, I do not have access to machine-shop nor experience as a machinist. I do use bullet swaging dies to fabricate projectiles. The manufacturer (Corbins) that I use, sells kits to make gas checks. You would be replicating that capability to punch out a specific sized circle of flat copper, then a separate die to create the cup.

If you make this, would be nice to see you post your results (especially photos). Good luck.
Negative, I do not have access to machine-shop nor experience as a machinist. I do use bullet swaging dies to fabricate projectiles. The manufacturer (Corbins) that I use, sells kits to make gas checks. You would be replicating that capability to punch out a specific sized circle of flat copper, then a separate die to create the cup.

If you make this, would be nice to see you post your results (especially photos). Good luck.
Semper fi Do or die.
I know some parts are a cage thread bolt. I wanna know hot to create the punch. I was even thinking of using a resizing die set up and just cutting s slit in that
 

NYECOGunsmith

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#4
I have the machine shop, and the skills to make the punches, dies and strippers to make my own gas checks.....but I buy them because it is far and away cheaper to do so. I can walk you through making the punches, dies and stripper if you like, but you will need a lathe to do it accurately.

Price pure copper sheets, or gilding metal sheets, or aluminum or zinc or brass (all can be used for gas checks) sheets don't forget to factor in the wastage, plus shipping, and the time it takes to make the tools, and knock out the disks and then turn them into cups, and the percentage of them that won't turn out useable, and you will see what I mean.

Problems you will run into are fine tuning the punch and disk die to get the right size disk, then getting the cup forming die, its punch and stripper sized right so the cup is formed with even thickness all the way around, and comes out with the walls of the cup the same height and thickness.

Failing to get the gas checks the right inside diameter, or the wall thickness and height the same all the way around, or achieving the right tension on the walls so that the gas check stays on the projectile, all of these lead to poor accuracy.

I'm not saying it can't be done, or shouldn't be done, just that you shouldn't expect results in accuracy, or cost savings, anywhere near what you will achieve with mass produced gas checks, not with home made tools made without machine tools or the skills to make them accurately.

It's a fun project if you have the right tools, and take the time to do it right, but even then, in the end, it's not going to save you any money, unless you have a large supply of the right thickness sheet aluminum, brass or copper on hand that didn't cost you much, or if you can get the right thickness aluminum flashing at a good price.

Well, maybe, now that I think about it, if you had a really large supply of empty soda or beer cans, and got the punch, die , stripper all sized perfectly for the thickness of the can aluminum (which is actually fairly consistent from can to can, within the same brand), you might be able to save a few dollars per thousand rounds, but I wouldn't guarantee that the can aluminum alloy will have the proper level of elasticity to hold it on the cast bullet base. Trial and error will tell.

There are tools out there available for purchase and set up for soda cans that will let you make your own gas checks at a fairly decent rate, and of uniform size.
The guy in CA who made them, if he is still in business, was a Charlie Darnall as I recall, and I think he called the tool the FreeChex Gas Check Maker, something like that. The original model was the I, but I think there were follow on models II and III, but I don't know if he is still in business or not. They ran from about $30 to $75 per caliber, depending on the model, I, II or III.
 

TexasJackKin

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#5
I would listen to NYECOGunsmith, I'm a guy that does a lot of impractical stuff, just for the fun of it. But homemade gas checks wouldn't be one of them. Could it be done?.....Sure....If you had drawings to work from, you might get something to work after a few tries, that kind of stuff is VERY dependent on material thickness, and condition. It's as much art as it is science.

I worked (Now retired) a number of years, as a Tool and Die Maker in the can industry making drawn and Ironed soup cans, maybe that background would make me fussier than most, when it comes to gas checks..... Could you make something that would work? Probably....Would it work as well as factory? Hard to say...... Don't get me wrong, if it's something you want to try, more power to you, I'd love to see the results!
 

echo1er

uber Member
#6
I have the machine shop, and the skills to make the punches, dies and strippers to make my own gas checks.....but I buy them because it is far and away cheaper to do so. I can walk you through making the punches, dies and stripper if you like, but you will need a lathe to do it accurately.

Price pure copper sheets, or gilding metal sheets, or aluminum or zinc or brass (all can be used for gas checks) sheets don't forget to factor in the wastage, plus shipping, and the time it takes to make the tools, and knock out the disks and then turn them into cups, and the percentage of them that won't turn out useable, and you will see what I mean.

Problems you will run into are fine tuning the punch and disk die to get the right size disk, then getting the cup forming die, its punch and stripper sized right so the cup is formed with even thickness all the way around, and comes out with the walls of the cup the same height and thickness.

Failing to get the gas checks the right inside diameter, or the wall thickness and height the same all the way around, or achieving the right tension on the walls so that the gas check stays on the projectile, all of these lead to poor accuracy.

I'm not saying it can't be done, or shouldn't be done, just that you shouldn't expect results in accuracy, or cost savings, anywhere near what you will achieve with mass produced gas checks, not with home made tools made without machine tools or the skills to make them accurately.

It's a fun project if you have the right tools, and take the time to do it right, but even then, in the end, it's not going to save you any money, unless you have a large supply of the right thickness sheet aluminum, brass or copper on hand that didn't cost you much, or if you can get the right thickness aluminum flashing at a good price.

Well, maybe, now that I think about it, if you had a really large supply of empty soda or beer cans, and got the punch, die , stripper all sized perfectly for the thickness of the can aluminum (which is actually fairly consistent from can to can, within the same brand), you might be able to save a few dollars per thousand rounds, but I wouldn't guarantee that the can aluminum alloy will have the proper level of elasticity to hold it on the cast bullet base. Trial and error will tell.

There are tools out there available for purchase and set up for soda cans that will let you make your own gas checks at a fairly decent rate, and of uniform size.
The guy in CA who made them, if he is still in business, was a Charlie Darnall as I recall, and I think he called the tool the FreeChex Gas Check Maker, something like that. The original model was the I, but I think there were follow on models II and III, but I don't know if he is still in business or not. They ran from about $30 to $75 per caliber, depending on the model, I, II or III.
thanks for the knowledge. I was going to use some room flashing or double up on some soda cans. Seen a lot of youtubers doing it lately.
 

echo1er

uber Member
#7
I would listen to NYECOGunsmith, I'm a guy that does a lot of impractical stuff, just for the fun of it. But homemade gas checks wouldn't be one of them. Could it be done?.....Sure....If you had drawings to work from, you might get something to work after a few tries, that kind of stuff is VERY dependent on material thickness, and condition. It's as much art as it is science.

I worked (Now retired) a number of years, as a Tool and Die Maker in the can industry making drawn and Ironed soup cans, maybe that background would make me fussier than most, when it comes to gas checks..... Could you make something that would work? Probably....Would it work as well as factory? Hard to say...... Don't get me wrong, if it's something you want to try, more power to you, I'd love to see the results!
Its going to a work in progress since I'm working from scratch. First I'll get some factory gas checks to start a new data load.
 

NYECOGunsmith

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#8
Good idea, make up some of your favorite loads with commercial gas checks (after measuring them for inside, outside diameter, wall thickness , wall height, and base thickness) and then make up some home made ones, try to get them close to the factory ones, use them in the same load and record the data.

You might hit on a combination of size, thickness and material source that works as well , or better than the factory stuff, then as long as you can source that material readily, go for it and save money.

Just remember every time you get a new supply of material (flashing, soda cans, beer, cans, whatever) make sure you measure several samples of it in different areas so you don't end up with a surprise in a load that no longer works.

If you think about it and have time, post pics of the process, good learning experience for folks here.
 

TexasJackKin

Breathng Free, at last
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2019 Supporter
#9
[QUOTE="NYECOGunsmith, post: 1267986,
You might hit on a combination of size, thickness and material source that works as well , or better than the factory stuff, then as long as you can source that material readily, go for it and save money.

Just remember every time you get a new supply of material (flashing, soda cans, beer, cans, whatever) make sure you measure several samples of it in different areas so you don't end up with a surprise in a load that no longer works.

If you think about it and have time, post pics of the process, good learning experience for folks here.[/QUOTE]

Yes, while working in the can industry our engineers figured out how to make the cans 0.0002 (that's 2/10 of one thousandth of an inch) thinner. it was suposed to save our plant over a million dollars a year. But, of course we had to re-work all the tooling to make that work. The point being, if you use cans, about the time you get it working, some big brained engineer will figure out a way to make them thinner.....
 

NYECOGunsmith

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#10
^^^^ Yup, or they could switch alloys on you to reduce cost, and the modulus of elasticity changes, and suddenly the gas checks that were perfect no long hold on tight, or they don't expand sufficiently to let you install them without crushing the walls and deforming the heel of the bullet.

And remember, it's the heel of the bullet that upsets accuracy far more than the nose, because if the gas isn't flowing evenly around the heel as the projectile leaves the muzzle, due to either a nicked / damaged crown, or the heel of the bullet being asymmetrical, that bullet is very likely to pitch or yaw, and there goes the accuracy.