Beer can gas checks

[Johansson81]

Since I have an endless supply of empty beer cans in my workshop I wanted to try and use them for my 300 Blackout loads, a Lee 155gn PCed bullet for plinkling up to 200meters.

I made myself a gas check punch tool for the single stage press which works just fine, but since the beer cans are quite thin walled the checks wont stick to the bullet base even after passing through the sizing die. Despite that I milled the gas check groove in the mold so that it matches the thickness of the GC.

Anyways, with a small bellmouth on the case made by modifying the powder drop die I can just put the GC on the bullet when placing it on the case mouth and seat the bullet so far that the case neck tension holds the GC in place.

So far it seems to work just fine, I havent pushed the velocities beyond 1700fps yet but they group just fine and no signs of leading.

Is there a downside to these thin walled gas checks? I assume they drop off as soon as the bullet leaves the barrel but why would that affect accuracy in any way?

A single copper gas check bought through Brownells in Sweden cost almost as much as the powder and primer together in the loaded round, so I am really saving money here.

[farmbif]

just a thought from left field, sometimes the tops of cans are a bit thicker than the rest of can, if you have endless supply might try material from can top.

[garandsrus]

You could try forming the gas check with two layers of beer can also.

[too many things]

they dont fly straight too drunk

[elmacgyver0]

If they work and you are happy with them, what is the downside?

[725]

This might require a serious investigation as to who makes the thickest beer can metal. Seems I remember the cans that look like bottles are thicker than the cans that look like cans. Happy searching.

[Hick]

You just invented another reason to drink beer-- whether it works or not you're a hero

[Johansson81]

Since I modified the mold I can´t use any thicker gas checks than this, I could from the start have ordered a sheet of suitable thickness but then the whole idea of being able to make the bullets all by myself would sort of fail.

I would really like to recover a bullet to see how the base looks, and if there are any cutting signs in the GC. Would shooting it into a 100 liter barrel of water work or would it just go through the bottom since it is a non-expanding design?

I´ll finish my morning coffee and go out to the shed and make some test loads to figure out how much powder is needed to reach 1800fps. That feels like a good compromise for this bullet. Good thing I have a Labradar at home and live next to a forrest, won´t have to go to the range to test them.

Cheers!
/Anders

[Winger Ed.]

The walls on soda pop cans are thicker than most beer cans.
Miller Lite 16 oz. cans that look like a bottle, are even thicker than soda pop cans.

[Johansson81]

The walls on soda pop cans are thicker than most beer cans.
Miller Lite 16 oz. cans that look like a bottle, are even thicker than soda pop cans.

I dont think I've ever seen one of those in store here in Sweden.

[Johansson81]

Here is a pic of the punch and a bunch of finished gas checks. No idea why the images end up sideways in the post.

[AntiqueSledMan]

Hello Johansson81,

I don't think it really matters if they fall off in flight, the purpose is for in the barrel.
I have heard of people placing a drop of super-glue on the bullet base before installing the check.

AntiqueSledMan.

[hockeynick39]

Those look absolutely fine. I use beer/soda can gas checks on all of my plain base boolits. This is also whether I powder coat them or lube them like usual. I have had no issues with any of the gas checks. Yes, most of them come off in flight and what was said in a previous post, it doesn't matter after leaving the barrel.
Pushing them to 1800 fps accurately shouldn't be an issue. Just bump the powder charge up by .1 grain per load and use a chronograph. Good luck and stay safe!

[JonB_in_Glencoe]

I've used popcan metal to make plain base GCs. I've found the boolit alloy needs to be fairly soft, like about 10 bhn, so when sized, the GC will squeeze into the base band of the boolit, and they stay on quite well.
So, depending on what alloy you are using, you may considering making your mold to drop a plain base boolit.

[Johansson81]

Hello Johansson81,

I don't think it really matters if they fall off in flight, the purpose is for in the barrel.
I have heard of people placing a drop of super-glue on the bullet base before installing the check.

AntiqueSledMan.

Couldn´t it be so that a flimsy gas check like this one would negatively affect accuracy if it was glued to the base but starting to break away at the edges? Better if it drops off directly after the muzzle.

Those look absolutely fine. I use beer/soda can gas checks on all of my plain base boolits. This is also whether I powder coat them or lube them like usual. I have had no issues with any of the gas checks. Yes, most of them come off in flight and what was said in a previous post, it doesn't matter after leaving the barrel.
Pushing them to 1800 fps accurately shouldn't be an issue. Just bump the powder charge up by .1 grain per load and use a chronograph. Good luck and stay safe!

I made some test charges this morning and ended up at 18.0 grains of RS36, didn´t want to shoot too many rounds since I did the testing in my back yard and it might upset the neighbours.

The 18 grain loads read in just around 1800fps so I think I am good to go, the primers are starting to flatten out but the edges are still rounded so no over pressure. 2" groups at 20m shooting without support is ok for me, if I had a scope and a bench rest they would have been much better. At least I know that they group fine without keyholing and other issues.

I've used popcan metal to make plain base GCs. I've found the boolit alloy needs to be fairly soft, like about 10 bhn, so when sized, the GC will squeeze into the base band of the boolit, and they stay on quite well.
So, depending on what alloy you are using, you may considering making your mold to drop a plain base boolit.

When you run the bullets through the sizer, won´t the gas checks wrinkle at the base? That happened for me when I tried to crimp them in place during sizing.

If it was possible to size the bullets base first they the gas checks would stretch out better around the base of the bullet I think.

[farmbif]

I was sizing gas checked bullets yesterday and checks were falling off. I wipe the base of bullet in a bit of lube and then size and they all stuck real well.

[JonB_in_Glencoe]

SNIP...


When you run the bullets through the sizer, won´t the gas checks wrinkle at the base? That happened for me when I tried to crimp them in place during sizing.

If it was possible to size the bullets base first they the gas checks would stretch out better around the base of the bullet I think.

I do size them base first. No wrinkling on base.

[Johansson81]

I do size them base first. No wrinkling on base.

How do you keep the bullet tip from deforming?

[Winger Ed.]

I dont think I've ever seen one of those in store here in Sweden.

Hmm,, too bad.
I think the Foster's beer from Australia is also in a thick walled can.
You might find them there, and its good stuff too.

Something else that might do for ya is those throw away foil baking pans at the grocery store.
The ones we have here are pretty thick, more so than a drink can.

[JonB_in_Glencoe]

How do you keep the bullet tip from deforming?

I use a Lyman lubesizer to seat/crimp the GC, with the correct Top Punch to fit the boolit nose.