Yet another head space question

[CatShooter]

Catshooter, I ask the question: "Do you guys just make this stuff up?" The drawing you posted is from SAAMI, the SAAMI case drawing is absent of a head space symbol. Had you included the chamber drawing you would have an ideal what a head space symbol looks like.

A member of another forum called SAAMI in an effort to get someone at SAAMI to agree with him, someone at SAAMI screwed up? SAAMI has been around long before the Internet. SAAMI also has a glossary of terms, in the glossary of terms SAAMI says reloaders are confused about clearance between the bolt face and case head.

F. Guffey

So that line and datum reference is there for decoration... OK, I get it

You don't!

 

[fguffey]

So that line and datum reference is there for decoration... OK, I get it

You don't!

No you don't, yes I do. The datum is a line on a drawing, in the real world it is a round hole, the round hole diameter for the 308 W is .400". The .400" hole is 'measure from'. To measure the length of a case for comparison it is not necessary to use the .400" hole, when measuring the length of the case for SAAMI comparison the hole can not have a radius, bushings purchased by reloaders to convert dial calipers comparators has a radius. I make datums.

F. Guffey

 

[CatShooter]

So that line and datum reference is there for decoration... OK, I get it

You don't!

No you don't, yes I do. The datum is a line on a drawing, in the real world it is a round hole, the round hole diameter for the 308 W is .400". The .400" hole is 'measure from'. To measure the length of a case for comparison it is not necessary to use the .400" hole, when measuring the length of the case for SAAMI comparison the hole can not have a radius, bushings purchased by reloaders to convert dial calipers comparators has a radius. I make datums.

F. Guffey

The ones I purchased had radius'...

... for about an hour - they do not have radius' anymore.

I have fun

 

[fguffey]

http://www.saami.org/PubResources/CC_Drawings/Rifle/308%20Winchester.pdf Here is a link to the 308 W, notice the B is for basic and the chamber drawing has a head space symbol.

Rather than present the information in a biased manner I included the legend/notes.

Head space applies to the chamber only.

F. Guffey

 

[dkhunt14]

Then I guess all the so called experts Like Hornady, RCBS and all the others that make reloading manuals are wrong. They call it headspace when you bump the shoulder and that is what you are doing when you resize it. If you are bumping the case .001 when you size you are doing the same thing as moving the chamber out 001. It don't matter if you move the case or chamber it is still headspace. Even on a belted case except you can use the belt to headspace and that is what all the books call it. Just because Saami puts a symbol on there drawing, it is just their way of showing headspace line so some idiot doesn't read the wrong line. Maybe you should read the quote in the box at the bottom of the page. Matt

 

[CatShooter]

Then I guess all the so called experts Like Hornady, RCBS and all the others that make reloading manuals are wrong. They call it headspace when you bump the shoulder and that is what you are doing when you resize it. If you are bumping the case .001 when you size you are doing the same thing as moving the chamber out 001. It don't matter if you move the case or chamber it is still headspace. Even on a belted case except you can use the belt to headspace and that is what all the books call it. Just because Saami puts a symbol on there drawing, it is just their way of showing headspace line so some idiot doesn't read the wrong line. Maybe you should read the quote in the box at the bottom of the page. Matt

Yup.. they are all wrong - Guffy is going to straighten out the whole world, so we call things what HE wants them to be called.

 

[gsg5pk]

Buy a set of go gauge & no go gauge

These will tell you everything about your headspace.

 

[dedogs]

CatShooter, NO he won't.