Does any one make a 25 cal aluminum gas check ? The Hornady GC are to tight and wont seat fully.

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Michael S posted this 3 weeks ago

  I have a Ideal 257420 mould that is casting the shank to big for a factory Hornady gas check to seat fully and proper. I can't even finger start it even.  Ed Harris suggested I try an aluminum gas check to see if a thinner GC would work. Other then the GC coming out to big my Ideal mould casts a pristine cast bullet. 

  I figure I would ask if any one has any they have made and if they would sell me a few so I can test to see if aluminum would work. 

GOD, United States of America, US Marine Corps, Family, Self

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GP Idaho posted this 3 weeks ago

Michael:  You might try Sage checks.  Also, Al at Noe makes a gas check expanding punch and a Gas check seating die that gets the checks on tight and square. An easy homemade expander can be made from a 1/4" bolt shank rounded a little bit. Gp

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Michael S posted this 3 weeks ago

   I have been using the Lyman gas check seating tool to seat our gas checks. It works best if I pre start the GC on the shank. But unlike all of our other cast bullets needing a GC I cannot pre start the Hornady on this 257420 bullet. Even rapping it on the table like I have to do with my Ideal 311291 cast bullet to have it started square does not work with my 25 cal one.

GOD, United States of America, US Marine Corps, Family, Self

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Coydog posted this 3 weeks ago

I have got the expander from Al and I got it for one of the molds for 22 cal and the GC did not go on too good so I talk with Al  and he set me up on what I need and after I got it  no more problems. I been use Gator and Hornady GC .I do use what I have left of Lyman for some of the cals. I got  , went with in the end with Gators they are like Hornady 

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rmrix posted this 3 weeks ago

Odd! I had the exact same problem with the same Lyman mold number.

Years ago  I got a used single cavity 257 420 just to see if my Winchester 1982 even liked the design. Some loads shot okay using these cast bullets, but having to make one bullet at a time to feed a repeater was not great. Standard Lyman and Hornady gas checks fit fine and I never even thought about a check NOT going on any bullet I have in inventory.

So, I find a 2 cavity mold for sale and got it.That should double the production! The mold was in good shape for used and made nice bullets. To my great surprise the checks won't fit!  No mater what they don't go on. The bullet shank is just too large! I have checks from Hornady and Lyman as mentioned and a few sizes from Sage (aluminum) and none would go on!

I did not know this was even a common problem nor did I know NOE made something to address it until later.

I was going to sell the mold and thought, that's not good - I either disclose the problem or not sell it. I would not want to stick someone whit a bum mold.  Hmmm, come to think of it, someone sold it to me..... Hmmm. I  guess people do that kind of thing.


Anyway. Having a metal lathe, I dreamed up turning a piece with a bottom that fits into the press ram like the shell holders and the top end of this piece has a button, the right size of course, to expand the GC. To screw into the top of the press I made a 7/8-14 part with a flat faced bottom to squish the check down on the button . It worked great right off the bat. Place a check on the button and raise the ram.   Gas checks fit fine and go on square. Just an unneeded additional step.

IF you like the Lyman mold and the bullets from it I would recommend getting the NOE stuff to enlarge the checks.  If not, get a reproduction of that Lyman 257 420 from NOE. He makes great molds.



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John Alexander posted this 2 weeks ago

" It worked great right off the bat. Place a check on the button and raise the ram.   Gas checks fit fine and go on square. Just an unneeded additional step."


You aren't alone with one bad mold Michael.  Half the molds I own bought over the last 65 years require some such additional steps with the checks on the market today.

Luckily I have a friend who rescued me with a cunning little seater that solves the problem for some of my molds BUT ONLY WITH THOSE DAMNED UNNEEDED ADDITIONAL STEPS.

Gas check specs apparently changed 15 -20 years ago. Fully half of my old molds won't take the gas checks now on the market.  When I can scrounge ancient gas checks from someone getting out of shooting cast, they always fit fine.  

I am amazed at how meekly cast bullet shooter put up with these mismatches.

The fact that there is a market for various devices to seat undersized checks or expand the checks suggests that this isn't a rare problem.

I keep hoping that one of the independent gas check makers that have sprung up will offer an option of oversized (or old sized) checks. I suspect there is a market.


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Michael S posted this 2 weeks ago

  I got a hold of Al at NOE and he did have the 25 cal part and main part in stock.  I placed my order for August 1st 2020

  Thank you for telling me about the tool. I know NOE makes moulds I have several of his GR2 HB,PB wad cutter moulds for 38 cal 44 cal 45 cal and and a 35 rem GC,PB mould and the top punches he makes for them. Excellent quality!

GOD, United States of America, US Marine Corps, Family, Self

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Tom Acheson posted this 2 days ago

At one time people were annealing gas checks to make them soft and more pliable and improving the check’s “willingness” to go onto the base.

One of the items NOE offers is a tool to slightly bevel the base of the bullet producing a slight chamfer, relieving the sharp corner of the bullet base.

A softer alloy could be slightly smaller in diameter, improving the check’s ability to go onto the bullet base. Some of our applications do not require super hard bullets. Hard alloy  = “fatter” but lighter bullets. Soft alloy = not as fat bullet but heavier.

Not sure if any of these are solutions to your challenges.





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Michael S posted this 2 days ago

 My wife and I will cast the mould in our WW and see if it helps. I got the NOE tool and I am still trying to figure out how to use it. My Hornady gas checks do not fit on the mandrel part of the NOE tool.When I am raising the mandrel up with the GC wobbling on the mandrel since it wont fit on it, I get a random contact each time. Doing this step one handed might be affecting the out come as well. So I am getting un even GC spread which ends up to loose to go on any of our 25 cal shanks and when I try to seat it using the Lyman 4500 lube and sizer with the Lyman gas check seating tool. The gas check stays in the H and I .258 sizing die. 

 If it were not for the fact that most of the rifle calibers that my wife and I are learning to cast bullets for require a GC for the speed that the bullet pushes at, I would do plain base across the board. These GC's are proving to have more of a learning curve to install then the learning to cast bullets is.

  Once I learn to use this GC tool that NOE made maybe the 25 cal curve will shrink.  

GOD, United States of America, US Marine Corps, Family, Self

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Ken Campbell Iowa posted this yesterday

mike ... as you know, been following this .. would be glad to help if i can ... email me a sketch with numbers of what you need ... 

i might mention i haven't shot a gas check in 30 years ...  it is amazing what a 1450 fps 80 gr cast will do to a bean can full of water ...   and my 45-70 with a stubby 230 gr at 1250 fps will finish one off real good if the can is still kicking ...  remember, the last buffalo was killed by at bullet at 1300 fps at the muzzle ...

to be fair, back then my gas check loads were usually more accurate, even at lower velocities .. i just don't think they are 3 cents more accurate for my simple fun use.  i probably enjoy just working the guns as much as blowing up the pop cans ...


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Michael S posted this yesterday

 My wife and I casted 70 ct that mould in WW yesterday. Sadly the GC did not go on those either.  Since we had the pot on we casted the Saeco #453  45 cal WC 236.4 gr 

GOD, United States of America, US Marine Corps, Family, Self

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