Alum. gas check break through.

[JeffinNZ]

Team.

From day one I have had erractic results with my Freechex made from aluminium (aluminum to you guys ). I had been blaming the alloy etc.

I had been forming the checks with the anvil sitting in a slab of wood in my vice so when the check formed it dropped down a hole in the wood into the can below for collection. Quick and efficient but this method was producing checks that were not uniformly formed.



Now I am forming per Charlie's instructions and forming the checks on a hard surface and HEY PRESTO, great results. Today I shot 10 rounds through the No4 Mk2 and at 100m/110y 7 are in 1 1/2 inches, 1 is a little right (I called that) and dang it if I didn't drop 2 a bit low that I can't explain. (Buckshot will say that is the Almight keepin' me humble) Checks were 2 ply alum 11 thou litho plate/4.2 thou soda can. Photo tonight.

Further, yesterday I shot Freechex in my .303 Pygmy using 19 thou alum and they shot GREAT. First round went a shade high; possible neck tension issue as that round was a shade loose in the neck. See photo following:



Soooooooooooooo, I take back anything I said about alum checks. They work great. It's very much a factor of using metal that COMPLETELY fills the void between gas check shank and groove and how well the check is created.

[JeffinNZ]

Team.

Here is the .303 Brit group from today.



The 8 at the tip of the bullet I called/felt but the two low shots have be baffled. I would like to think as they are close together in the same area I pulled them also as all my shooting with this rifle is done front hand supported, elbows resting - not benchrested. This not withstanding the other 7 rouns are in less than 1.5 inches which is tres repectable for a Lee Enfield.

[JeffinNZ]

Team.

I shot the No4 MkII .303 Brit today. Using both front and rear sandbags (I usually shoot front hand supported, elbows on bench). I put 10 rounds through the old girl using the 2 ply alum checks. The last two rounds contained bullets with small flaws in the noses - I saw these after I had seated the projectiles as I was in a hurry. I fired these two rounds last and one went into the group, the other did not and is the shot in the 'X' ring. The main group of 9 rounds is 1.5 inches at 100m/110y. Load produces 1640fps with the 205gr bullet over 20.6gr AR2205/H4227. Further, the 4 shots in the far left of the group were the first fired and I had my chest resting against the bench, a stanch I changed shortly thereafter as my breathing was not comfortable. I believe this change moved the POI right a shade. Hence the egg shaped group.

Either ways this conclusively shows the alum checks work on par with commercial checks.

[Just Duke]

Great results Jeff. What grain weigh?

[Alvin in AZ]

Hmmm...
Do you suppose the aluminum oxide coating on the gas
checks will smooth up a bore any? :)

Al2O3 is 9.0 on the mohs scale.

Alvin spelling aluminum wrong on purpose in AZ ;)
ps- did I get the right number of oxygens this time? :)

[JeffinNZ]

No oxide. The material is coated.

[Boerrancher]

Jeff,

I am going to take partial blame for your poor results in the past. You had posted a pic of your set up in the past for making them. I was going to post and tell you about it, got distracted, and forgot. CRS as we discussed per PM. LOL Anyhow that is some great shooting. I am glad the homegrown gas checks are coming into it for you. Your Package arrived, it is at the post office, the wife will pick it up today.

Best wishes and happy shooting from the Boer Ranch,

Joe

[JeffinNZ]

That's mighty decent of you Joe. Taking responsibility for me being a dumb ass and all.

[Meatco1]

Jeff, I enjoy reading your updates. I'm still on the fence about making my own, or continue buying the damm things at outrageous prices!!

Thank you,

Richard

[Alvin in AZ]

No oxide. The material is coated.

The aluminum was coated with what exactly? ;)
And was the aluminum cleaned in an inert atmosphere or a vacuum? ;)
That fancy of aluminum is prob'ly worth more than Cu gas checks, suppose?

Aluminum's got an oxide coating on it... even through oil, oxygen will find
its way to the aluminum. Just the way it is. Chromium, titanium and many
others are the same way.

Believe it? :)

Alvin in AZ

[madsenshooter]

Alvin might be right, most litho plates now a days are anodized, which is to say:

Anodizing, or anodising, is an electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts. Anodizing increases corrosion resistance and wear resistance, and provides better adhesion for paint primers and glues than bare metal.

To further define that though we must figure out what passivation is:

In the context of corrosion, passivation is the spontaneous formation of a hard non-reactive surface film that inhibits further corrosion. This layer is usually an oxide or nitride that is a few atoms thick.

So, I'd say litho plates, free or not, are probably not the way to go, there's a plastic coating on the inside of the beverage cans though. Maybe someone should reslug their bores after 1000 rounds or so and let us know how much wear and tear it's taken! Might be ok for emergency use.

[docone31]

One more way we remain independant!
Great shootin with that #4. I should be so lucky.
I had to go paper, I got 20ft of berm groups with gas checks.
Lookin good.

[randy merta]

Jeff could you post a pic of your rifle. I am having a fancy of a fit wanting an old military rifle again. And what type of gas check making device do you have? Nice shooting!
Randy

[hunter64]

Jeff in NZ: I have some old #3's and #4 rifles that I take to the range once in a while to streach there legs. What mold are you using for the bullets?

[docone31]

Hunter, I use the C312/185R by Lee Precision. It works for me. I use it both in casting, and paper patching.
I wish I had groups like that with casting.

[JeffinNZ]

Jeff in NZ: I have some old #3's and #4 rifles that I take to the range once in a while to streach there legs. What mold are you using for the bullets?

It's a CBE 313 215. 205gr in WW. Jim's .303 bullets will not be beaten.

[tcrocker]

Where do you get the stuff to make your own gas checks?

[Alchemist]

Where do you get the stuff to make your own gas checks?

Check the group buy forum...Patmarlin is doing check makers over there. He also has a copper sheet group buy.

Cheers

[S.B.]

It appears your not using any lube in grease grooves, how's leading in the bore? Bullet in bottom picture doesn't appear to have check on it?
Steve

[PatMarlin]

Outstanding ...! Great shooting Jeff ...

Aluminum obviously works and shoots well, but personally I can't bring myself to use anything but copper down my bores. Just the thought of taking a chance with Al bothers me.,

We really don't know what that coating is, and is it the same from one manufacturer to the next? Does is help or harm?

A firearm that I use occasionally or don't care about would be different I guess, but I'm attached to all of them ..