Head space Gages

OP :

The L E Wilson gage is a more precise gage . I just did some test comparing them both . Although they both seem to work well . I was able to get a more consistent measurement from the L E Wilson gage .
 
Look at any SAAMI drawing.
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Look at SAAMI? That never works, we have a member that insisted SAAMI used the symbol for head space on the case and chamber drawings. He was so emphatic he called SAAMI, the symbol for head space is absent on case drawings. They give a length when measured from a datum, for the 30/06 that would be .375". The length is measured from a datum to the case head.

Then he went on to tell us what SAAMI said. Even though SAAMI says many are confused about head space, the case does not have head space and the symbol for head space is absent on their drawings. Then there is R. Lee and his book on modern reloading. R. Lee included the location and diameter of the datum on his case drawings. And no one ever list him as a resource.

F. Guffey
 
Good grief.

SAAMI 30-06 headspace* drawings/specs (p56):

Chamber: 2.0487"(Min) - 2.0587"(Max)
Cartridge: 2.0456"(Min) - 2.0526"(Max) (Specifically: 2.0526 - 0.007")

Once the shooter/reloader realizes there ARE dimensions to work with, life gets a whole lot lot clearer



* by definition shown as distance to 0.375" radius to shoulder from base/bolt
 
Once the shooter/reloader realizes there ARE dimensions to work with, life gets a whole lot clearer
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Good grief.
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* by definition shown as distance to 0.375" radius to shoulder from base/bolt
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Sounds like you made that up. what is radius to shoulder and now the case does not have a case head and the bolt does not have a bolt face.

F. Guffey
 
Sorry -- 0.375" Diameter of the shoulder
But had you looked the SAAMI drawing, the term would have been
obvious, ...as too the fact that it's a specification, not imagination.

(You have looked at the SAAMI drawing haven't you ?)
 
(You have looked at the SAAMI drawing haven't you ?)
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Looking is one thing, understanding what is being looked at is another. There is no symbol for head space on the case drawing used by SAAMI. R. Lee uses the datum location and size on case dimensions. R. lee does not furnish chamber drawings.

Everything does not have head space and every gage is not a head space gage.

Good grief.
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A member called SAAMI like SAAMI made a mistake or, they were unaware of the mistake. On the phone it is necessary to be nice to all inquires. SAAMI does not give head space for a cartridge in their drawings, reloaders assume. I have case gages, I make case gages, I make head space gages, I have a slight advantage, I can measure the length of the chamber form the shoulder to the bolt face in thousandths. Most are stuck with a go-gage, or a no go-gage or a field reject length gage.

It requires a few tools and a good understanding of the 'datum'.

F. Guffey
 
(You have looked at the SAAMI drawing haven't you ?)
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The question should be 'Why did the member of this forum call SAAMI?'

He could not find a head space symbol on the case drawing after insisting it was there.

F. Guffey
 
Datum/30-06 = 0.375" diameter of shoulder.
Simple.

Do you REALLY need a big Day-Glo Orange label with "Headspace Here" when the drawing is so incredibly clear?
 
Most reloaders can read a map, most maps have a legend, SAAMI uses a legend, in the SAAMI legend for case drawings there is no mention for the symbol for head space.

F. Guffey
 
mikld, I have no trouble understanding wogpotter, if a reloader wants to determine the difference in accuracy between two gages it helps to understand the 'datum'. I make datums, I collect datums and on occasions I sneak up on owners of datums that do not understand 'the datum', when that happens I purchase them.
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Guffy, once again you completely missed my point. Re-read it, without thinking it's an attack, and see if it makes sense...
 
Most reloaders can read a map, most maps have a legend, SAAMI uses a legend,
in the SAAMI legend for case drawings there is no mention for the symbol for head space.
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That's because it's obvious.

But I admit to exhaustion, and will let readers draw their own bottom
lines as to practical understanding & application of reloading Headspace. :D
 
I thought it was cowbell we needed more of .
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Sorry, but cowbell is not a headspace term. It relates only to powder measure size, specifically Lee dippers. Cowbells do not have headspace or it would be so designated on SAAMI cowbell drawings.
 
As the loader with limited funds for tools. I am using the Wilson gage for a quick peak at the case.

Although I have been using the Redding S type dies to size with a feeler gage under the case on the shell holder to fine tune the bump.

Isn't that what we are looking for?
 
Longshot...

Unless you have a Case Headspace Comparator Set and have established the case headspace dimensions that fit your particular chamber, "bumping" the case -- whether by feeler gauge or not -- leaves you no less blind than simple FL resizing.

Case thickness/hardening & springback vary by age, manufacturer, lot -- and resizing lube effectiveness.

(Oh... and you need a complete set of Datums too) ;)
 
So here I am with a case that is getting tight in the chamber. Or could I say tight in the gage.
So I put a .008 feeler in the case holder and run the case up into the die. I put the case in the gage or should I say chamber and close the bolt gently. If it doesn't fit I use a .006 feeler under the head and runr up. I try again until the bolt closes easy. That is a perfect fit the way I understand it.

Am I not correct?
 
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