free checks revisited with out theories

[kjg]

I'm asking a far fetched question with out the theories and arguments,now I also have the tool and mr. charlie took care of a problem for me and now its back in hand, I have notices all boolits from different mold have tapers, and straight shanks, the straight shanked ones take two cheks inorder to stay on the bollits, without (as per charlies direction) drop of super glue,diam of thickness .010 on the taperd one they need three check with out super glue, recently found alluminum sheets used for roofin flashing that mics out to .0115 havent bought it as of yet, rith next to them was copper flashing, it was miced at .0055, , I guess I'm goingbto have to try some too see if it works, anyone else have opinions on this with out the cray theroy discusins .kjg

[Boerrancher]

First off, for a gas check to be totally effective it must be thick enough to seal the bore off when fired. I don't think any one here will disagree with this, as most of the old timers know leading is cause mostly by gases blowing past the boolit. With that being said, the check has got to prevent that. I am not being critical of Charlie's tool when I say this, as I own one and have one that operates on the same principle. A 0.005 in thick beverage can is not going to prevent blow by.

You have discovered that you need multiple layers to get them to hang on by themselves. In discovering this you are on your way to having a homemade gas check that will work, but before you go out and buy material, you need to know how thick you need it. There is a simple formula that will do this. Here it is.

Slugged bore dia - boolit shank dia (at the largest portion for the tapered ones) / 2 . This will give you the minimum thickness you need. What I have found for optimal performance is 1 to 2 thousandths thicker than the min. needed. Due to the "springyness" for lack of a better word of the material, when seated and sized it will expand back out a thousandth or so giving a tighter seal.

If the check still is not tight enough to suit you, and magazine and chamber space permits, seat the boolit to where it is still in the neck. If it doesn't, lightly pack the empty space in the case with wadding. I use toilet paper, but some use other types of materials. The wadding will keep the check in place until there is sufficient pressure against it to hold it there.

Also, if you can't find the exact thickness of material you need, as you have discovered already, you can use two pieces to get there. They don't even have to be like material. Most of the checks that I make are between 11 and 12 thousandths thick for my 30 cal rifles.

If you have any questions feel free to ask here or PM me, I will help all I can. I have been casting for a bit over thirty years and am still learning. I am curious as to what others have to say on this topic.

Best wishes from the Boer Ranch,

Joe

[Bass Ackward]

Slugged bore dia - boolit shank dia (at the largest portion for the tapered ones) / 2 . This will give you the minimum thickness you need. What I have found for optimal performance is 1 to 2 thousandths thicker than the min. needed. Due to the "springyness" for lack of a better word of the material, when seated and sized it will expand back out a thousandth or so giving a tighter seal.

If the check still is not tight enough to suit you, and magazine and chamber space permits, seat the boolit to where it is still in the neck. If it doesn't, lightly pack the empty space in the case with wadding. I use toilet paper, but some use other types of materials. The wadding will keep the check in place until there is sufficient pressure against it to hold it there.

Also, if you can't find the exact thickness of material you need, as you have discovered already, you can use two pieces to get there. They don't even have to be like material. Most of the checks that I make are between 11 and 12 thousandths thick for my 30 cal rifles.

Joe



Excellent advice.

No theory, just fact.

Check thichness is different for different calibers. I believe that 35 caliber is the thinnest check sold. 45 is another problematic diameter because Hornady makes one check for use from .451 up to .461 or more. So if you are sizing that check at say .461, it will spin on the shank and it won't have the bite as if you sized the bullet .451.

So as you change mixes you will alter shank dimensions, you need to have enough extra play to maintain a good bite no matter what the material. Obviously, .010 is nothing to a Hornady check in 45 caliber, so I would want .006 - .010 excess above my sizing diameter for anything above normal velocity use.

I would think that these things would be excellent on PB as they get a STRONG bite the full thichness of the material. :grin: