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Old March 30, 2014, 09:48 PM   #26
riverratt
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Schill i have already thought of that as i posted earlier i have another 1.3gr of powder untill i see any pressure signs. Besides it has done the same thing with much liter loads. My bullets are seated a min. Of .004" off the lands. I did this by making a dummy blackoning the bullet with a lighter and chambering the round. I watched for the rifling marks, slowly seated the bullet deeper untill no contact was made. I then took a mesurment and seated the bullet another .004".

Just had an idea. Would that process work with setting my die? Just blackon the shoulder back off my die and work in slowly untill i see where it contacts the shoulder.

To answer a couple of questions it is a win 70 and i realy only load about 100 rounds per year sence i started loading pistol rounds. I use to enjoy shooting long distance (for me) with some friends of mine, but sence we moved i dont know where i can shoot out to 500yds anymore. Now i just use the gun for whitetail and only playing a little out to 200yrds so i dont feel i need to neck size only but i have thought of it to extend my case life. I have not had my gun's headspace checked because i had a rem. 700 that did the same thing

If i change my die should i work back up my load or will it not make that big of a differance, increaced case volume = lower pressure right?

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Old March 30, 2014, 11:24 PM   #27
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Just had an idea. Would that process work with setting my die? Just blackon the shoulder back off my die and work in slowly until i see where it contacts the shoulder.
No but you have the right idea . You can do that with cases that are to Long from the shoulder to the head for your chamber . You don't have to make any marks though . Put the empty cases in the chamber and close the bolt . If the bolt does not close turn your die in 1/32 of a turn( or how ever much these other guys say it could be 1/64 ) and size again . Try to chamber . Keep doing this till your bolt closes with no resistance . The case is now close to perfect for that chamber and the die is set now to size your cases to that size .

The problem your going to have right now is . Your cases are fire formed to your chamber so they should chamber no problem and should not make a mark . Even if they did and the bolt closed . That would be the max length you could size your brass . At that point you would need some way to compare that sized case to others you are sizing to make them the same . I use these http://www.midwayusa.com/product/479...ProductFinding and they work great . Bart and or Guffey make there own and could give you an idea how to do that .

That all being said . If your brass is like the picture that was shown above ( not mine the ones in post #8 ) you may be fine . Those cases look normal to me and I'd load them again .
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Old March 31, 2014, 09:07 AM   #28
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Have you had the rifle headspace checked? If that is, or gets, bad enough, you can have case separation on the first shot with a new factory case.

Jim
Let us pretend he had the head space checked and was informed the go-gage allowed the bolt to close. What if he had his own head space gage (the one that does not check the length of the chamber but the one that is .005" longer than a minimum length case from the shoulder to the head of the gage)??

If the bolt closes on a go-gage we should know and understand the chamber is at least as long as a go-gage, beyond that? We are still talking about it and we do not know3 the length of the chamber.

Let us pretend he took the rifle to a two 'gage smith' that wasted his time using a go-gage because he know it would allow the bolt to close then the smith went through the motions of checking the chamber head space/length from the shoulder to the bolt face with a no go-gage and found the bolt did not close. And I ask: What is the length of the chamber from the should to the bolt face?

And the answer? The bolt closes on a go-gage, the bolt does not close on a no go-gage and the reloader does not know the length of the chamber. When full length sizing the case could be .008" shorter than the chamber from the shoulder to the head of the case, or as some insist, the head space of the case is shorter than the head space of the chamber, and still they can not figure 'by how much'.

A reloader could measure the length of a new, factory over the counter round from the shoulder to the head of the case, then chamber and fire. After firing they could measure the length of the fired case from the shoulder to the head of the case to determine the difference in length between a minimum length/full length sized case. But, as soon as I hit the submit button someone is going to jump in with: You can't do that because of case memory, recovery, jump, snap, or spring back.

When a reloader determines the difference in length between a new factory minimum length case and a fired case they assume the case stretched between the case head and case body. I don't. I have had friends build wildcats and had 4 case head separations out of the first 10 rounds fired when fore forming cases, that does not mean the 6 that did not separate are/were good to go.

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Old March 31, 2014, 09:21 AM   #29
F. Guffey
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Just had an idea. Would that process work with setting my die? Just blackon the shoulder back off my die and work in slowly until i see where it contacts the shoulder.
A long time ago I had an ideal, There is nothing complicated about adjusting anything with threads, when adjusting the die to the shell holder I noticed the die was screwed into the press 'WITH THREADS', what kind? I did not care, how many threads per inch? I did not care, I was interested in the gap between the top of the shell holder and bottom of the die. SO? I decided to try a feeler gage, one that started with leafs as thin as .001" and went to at least .030". When sizing a case I adjusted the die off the shell holder .010" and started sizing fired cases, when I discovered the cases would not chamber I decreased the gap to .005", I then sized a few cases and attempted to chambering them, if they chambered with slight resistance I knew my chamber for that rifle was go-gage length.

Had the cases chambered with the .010" gap I would have know the chamber was longer than a no go-gage from the shoulder to the bolt face.

I could have gone to infinity, but I have rules, I have adjusted the gap to .014" when sizing cases for an M1917 Eddystone. The chamber is .002" longer than a field reject gage. The .002" longer than a field reject gage is .016" longer than a minimum length/full length sized case.

And the rifle has an exemption from that silly saying that starts with the "The firing pin strikes the primer, then? The whole thing including the case, powder and bullet takes off in an attempt to out run the firing pin etc., etc.,". My M1917s have killer firing pins.

F. Guffey

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Old April 1, 2014, 06:46 PM   #30
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This is a common thing when chambers are at the maximum headspace for bottleneck rounds and the full length die's set according to supplied instructions.

There is no simple nor easy solution for the masses. I wish there was.
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Old April 1, 2014, 07:32 PM   #31
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head seperation

rivtherratt
Do you have a gauge that attaches to the caliper that will measure the OAL off of the ogive of the bullet
Do you have the head spacing gauge for your caliper to measure from your fire formed casing and from there you set up your fl die.
These are the tools that I use and I also use the redding dies.
Steve
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Old April 1, 2014, 08:12 PM   #32
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I do not have thoes tools. All i have is st a basic setup that consist of a lee single stage press a lyman balance scale a set of calipers tumbler primer pocket cleaners deburers and an old set of lee powder scoops.

Everything i have learned was from my grandpaw. He has always been happy with handloading to factory accuracy for cheaper than factory rounds. Up untill about 3 years ago i was happy with that as well but i do enjoy a chalange so i started pushing the limets(not smart based on my experiance). I was however able to acheve almost 3100fps with a 165gr bullet before pressure signs. Now that i am a bit wiser i have realized that a deer dont know the differance between 2800fps and 3100fps. My goal now is to maybe get rid of my flyers (about 1 in 5 shots will land 1-2" out of the group) and posibly extend my caselife in the process.

Ps this place is great, i have learned more in the past 6 mo. Here then ive learned in 10 years of reloading.
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Old April 1, 2014, 08:41 PM   #33
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Head separation on rimless bottleneck cases is caused 99.9% of the time by excessive head clearance. Too much difference between chamber headspace and case headspace; the gap between the bolt face and case head is too much after the firing pin's driven the case hard into the chamber shoulder. Anything over .003" is too much in my opinion.

Sizing fired .30-06 cases following supplied instructions with the dies will resize the case close to minimum industry specs. If the rifle's chamber headspace is near max specs, there'll be several thousandths head clearance when the firing pin fires the round; .008" head clearance is not unheard of. The die needs to be set higher in the press.

When the round fires, its front half presses against the chamber walls and the back half stretches back. It's the back part stretching back that weakens the case wall about 1/4" forward of the case head where the brass is work hardened the most from firing and getting sized back down. That cracks after a few cycles and the head separates.

Proof loads with much higher pressures than normal don't cause head separation with cases the right size for the chamber. I've fired hundreds of proof loads in new cases put in chambers such that they've got no more than .003" head clearance and no case head separation at all. There's not even incipient separation felt by dragging a pointy thing inside the case and trying to feel a ridge around the case where it hangs up; no ridge exists.

There's tools available to measure case headspace; RCBS Precision Mic and Hornady LNL Gauge are two excellent ones. Measure a fired case headspace then set the die such that after its sized, its headspace is 1 to 2 thousandths less. Then you won't have case head separation. And a few dozen reloads per case is often possible doing this.
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Old April 1, 2014, 10:40 PM   #34
riverratt
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Thankyou to all that replied. Guess im gonna have to break down and buy something to mesure the shoulder on my casses. It does seem like a fairly simple prosess but nearly imposible without the proper tools.
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Old April 2, 2014, 07:22 AM   #35
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riverratt, Here's some pictures of how to use a 30 cent nylon spacer with a digital caliper to measure your fired cases then after sizing them to see how much their shoulder gets set back. Meanwhile, if there's an Ace Hardware store nearby, stop by it then buy a 1/2 inch long nylon spacer with a 3/8ths inch inside diameter. Then buy or borrow a digital caliper; a "must have" tool for reloaders in my opinion.

You'll also want to use these labels on your die so you can change its height in the press very precise to control how much sizing the cases get.

http://i860.photobucket.com/albums/a...justment-1.jpg



Note the last picture shows the case to have its shoulder set back .001 inch so it measures 2.047 inch. Perfect for best accuracy, feeding reliably and long case life.

Here's some drawings of the case and chamber that may help you see where the measurements I got came from. Note the "headspace" dimension for the chamber drawing:

http://www.saami.org/PubResources/CC...pringfield.pdf

Note also that the diameter of the reference point on both the chamber shoulder and case shoulder is .375 inch; same diameter as the hole in that nylon spacer. And after you full length size several cases, there'll be a small spread (few thousandths) across their headspace measurements. You may need to reset the die so the longest one is no longer than that of the fired case.
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Old April 2, 2014, 09:05 AM   #36
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Bart B., are you going to take the pictures are these pictures going to be pictures I have seen somewhere else.

Rather than assume I have the luxury of disagreeing, I am just going to disagree. I have little interest in helping someone spend their money on something they do not need. To understand the ‘datum’ the reloader must understand the hole is not the datum, the hole helps the reloader find the datum, meaning the flat surface the hole is drilled into is the datum. If the bushing has a tapper and or a bevel the datum is not the flat surface of the bushing but below the surface.

I make datums, I purchase datums, I collect datums. With an infinite numbers of holes drilled to an infinite number of diameters I have an infinite numbers of datums, try to remember, the datum is ‘measured from, the hole helps the reloader find the datum. “A must have tool” ?, The height gage works, the depth gage works, the dial caliper works, and remember, the dial caliper has is also a height gage/depth gage.

Then there is the Wislon case gage, a very precision gage, the Wilson case gage has a datum, Wilson case gage datum's have a radius, I checked. If a reloaders had the discipline of measuring before and again after they would know the length of a minimum length of a new, factory, over the counter case from the shoulder to the case head, and if they had discipline they they could measure the length of a fired case from the shoulder to the head of the case with a straight edge and and the companion tool to the press, the feeler gage.

Must have tool? Nothing beasts ‘must know’.

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Old April 2, 2014, 10:08 AM   #37
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Bart, It's funny you posted the picture with the nylon spacer to measure headspace. I did that same exact thing this past weekend, except I used my Hornady OAL gauge. I just found a insert where the case would fit to the shoulders and used it. It worked great.

Found out that a FL resized case is only .002" smaller that a fired case from my Rem 700.
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Old April 2, 2014, 11:17 AM   #38
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jw, one can use most anything to do this. That nylon spacer I used has an inner diameter that'll fit over lots of case neck sizes onto the case shoulder somewhere. It doesn't matter if the shoulder diameter it contacts at is the reference for SAAMI measurements. It's only the difference between fired and resized case headspace that matters when the die's set in the press.

The numbers read off the caliper are only relative to the spacer's dimensions. It just so happens that the .30-06 case shoulder's SAAMI datum/reference diameter is 3/8ths inch. So that same spacer could be used on any cartridge using the same body and shoulder diameters as the .30-06; .270 Win, .25-06 and even the .35 Whelen
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Old April 3, 2014, 07:06 AM   #39
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Bart B. Next you should suggest reoladers purchase R. Lee's book on modern reloading, R. Lee furnishes case drawings showing the diameter of the datum and location of the 'line' from the case head.

And, reoaders should be advised not to get into mortal combat with SAAMI and his specifications. One day reloaders will learn to measure the length of the chamber from the shoulder to the bolt face, after that? SAAMI specifications will become something that is 'just nice to know'.

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Old April 3, 2014, 07:10 AM   #40
F. Guffey
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Bart, It's funny you posted the picture with the nylon spacer to measure headspace.
Funny, because the case does not have head space, the case has length, the length of the case off-sets the length of the chamber to reduce all that case travel.

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Old April 3, 2014, 07:17 AM   #41
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purchase R. Lee's book on modern reloading
????

I'd rather ask folks to download the drawings direct from SAAMI's web site so they don't have to pay for that information. This way, they can get info for only the cartridges they have interest in and not have to pay for hard-copy information they don't desire.

For chamber and case drawings:

http://www.saami.org/PubResources/CC...0-%20Rifle.pdf

For cartridge velocity and pressure specs:

http://www.saami.org/specifications_...essure_CfR.pdf

And the industry standard as well as what's commonly used by everyone else (the rest of us) for "case length" is the distance between case head (specifically, the face thereof) and case mouth. Where the shoulder is doesn't matter. That's why case trimmers are used to trim the case at its mouth back to some shorter "length." And SAAMI's glossary sets the standard:

Quote:
CARTRIDGE CASE LENGTH
The dimensions from face of the head to the mouth.
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Old April 3, 2014, 08:47 AM   #42
F. Guffey
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Bart, It's funny you posted the picture with the nylon spacer to measure headspace.
Quote:
Today 07:17 AM
Bart B. Quote:
purchase R. Lee's book on modern reloading

????

I'd rather ask folks to download the drawings direct from SAAMI's web site so they don't have to pay for that information.
I could ask "How is that working out?", You were bragging to jwroland about the diameter of the hole in the in the bushing, something about it is not necessary the hole match the hole diameter listed in SAAMI specifications. That is true but only for comparators.

Quote:
And the industry standard as well as what's commonly used by everyone else (the rest of us) for "case length"
Back to how that is working out, 'commonly used by everyone else (the rest of us) for "case length", the L.E. Wilson case gage is not a head space gage it measure the length of the case from the shoulder of the case to the head of the case, it also measure the length of the case from the head of the case to the mouth of the case. The case has two lengths, one from the shoulder of the case to the head of the case, the other from the head of the case to the mouth of the case.

I doubt everyone wants to have you include them in 'used by everyone else' because there are a few that that understand the Gracey and Garard case trimmers use a case holder that allows the case to be trimmed by the length of the case from the shoulder to the case mouth, not from the head of the case to the case mouth.

I could ask 'WHY?' As you have said "I am the only one" that understand the chamber has a length from the shoulder to the bolt face. Not all chambers have the same length from the shoulder to the bolt face. I have one chamber that is .016" longer from the shoulder to the bolt face, that chamber is .016" longer than a minimum length sized case. That chamber is longer than a go-gage length chamber from the shoulder to the bolt face by .011". The standard, common, everyday 30/06 case is 2.494", if I trim my cases to 2.494 I shorten the neck .016" shorten than necessary, I do the logical thing, I add the .016" to the trim length or I use a Gasey case trimmer, one more time, the Gracey case holder holds the case and trims the neck length while setting on the shoulder, the case body is hanging out and held by the hand.

I said the case has a length, I did not day the case length was ?
The case has a length from the shoulder to the head of the case. The chamber has a length that is measured from the shoulder of the chamber to the bolt face.

Back to funny, in part of your response you claim there is head space and head space clearance, then you claim the case has head space. I am curious, how many members are writing this stuff? if only one he needs to agree with himself.

And for a short while I was thinking some of your response reminded me of me? And then? I got over it.

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Old April 3, 2014, 10:33 AM   #43
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Guffey : You may be right but fighting what IMO will become a standard talking point is a waist of time . I believe using the term Case head space will become an excepted way of describing the length of the case from the shoulder to head .

There is already big name companies using the term . It will become a main stay . Quit fighting it .
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Old April 3, 2014, 11:10 AM   #44
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Originally Posted by Metal god
I believe using the term Case head space will become an excepted way of describing the length of the case from the shoulder to head.
Far from will become, long since HAS become... it just hasn't made the official glossary list.

Reloaders have been using the term "case head space" and derivatives for decades. The first (and only) person I've ever seen/heard object to the term is Mr Guffey.

The strange part to me is that SAAMI (apparently)I has no name whatsoever for that measurement, at least in their official glossary. I actually tried to call them this morning but only got a voicemail. I'll try again and leave a message this time.
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Old April 3, 2014, 11:24 AM   #45
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That is an incredible waste of brass. Properly sized cases can be reloaded literally dozens of times.
4 Reloads is what I was told too. It's a value judgement. I could probably get more than that if I didn't do anything differently. I could probably get a lot more if I neck sized. I could probably get even more-more if I anneal the brass every so often.

For now, I stick with four and research those processes. What I lose in brass "value" I make up for in peace of mind not having to worry about a case separating and getting stuck. Sure it's ultra conservative, but that's safest for me at this stage.
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Old April 3, 2014, 11:29 AM   #46
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So... I just got off the phone with the guy at SAAMI. He was quite pleasant. He is aware that the measurement is commonly referred to as "case head space" and is aware that even SAAMI members (such as Hornady) use the term.

He says SAAMI doesn't use the term because some cartridges have a shoulder datum line and do not headspace on the shoulder. Examples would be 7mm Rem Mag and .357Sig.

The only official "name" for the measurement is an "alpha-numeric character". I don't know what it is, as I don't see it right off hand in their drawings.
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Old April 3, 2014, 12:16 PM   #47
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He says SAAMI don't use the term because some cartridges have a shoulder datum line and do not head space on the shoulder. Examples would be 7mm Rem Mag and .357Sig.
Thats interesting to me . I'd think "case head space" would be just that regardless as to where it's measured from or how you measure it . It's the part of the case that fits in the area of a given chamber better known as the chamber's head space .

I don't use any belted cases but I'd think there is or could be a way the measure there case head space .

As for the 357 sig (Qoute from wikipedia)
Quote:
According to the official C.I.P. (Commission Internationale Permanente Pour L'Epreuve Des Armes A Feu Portatives) 2007 rulings the .357 SIG head spaces on the shoulder (P2-H1). Some US sources concur this C.I.P. ruling.[4] US reloading supplier Lyman once published the .357 SIG head spaces on the case mouth (H2).
sounds like there is some dispute as to where the case head space on the 357 sig is measured from .
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Old April 3, 2014, 12:42 PM   #48
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sounds like there is some dispute as to where the case head space on the 357 sig is measured from .
The problem is one of technical design and theory versus the reality of real guns and brass.

The only point in the phone call with the SAAMI guy was a little less than pleasant was when he brought up .357sig and said it's headspaces on the mouth. I started to say something and I said it "...headspaces on the mouth, in theory..." and he cut me off, stating that "it's not a theory, there's absolutely no question, you can check the diagrams."

I didn't argue with him, but I did tell him that I do load .357sig and none of my cases are long enough to headspace on the mouth. The more detailed story that I didn't get into with him is that I have loaded the Sig with 3 different brass brands in 3 different barrels. Of those, I have yet to see a SINGLE case that was long enough to headspace on the mouth in a SINGLE barrel.

It's not even close, every case is MUCH to short to reach. They either headspace on the shoulder, if you size them so they do, or much more likely they headspace on the extractor.

Fact is, most semi-auto pistol rounds are actually headspacing on the extractor, no matter what the SAAMI diagrams say.
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Old April 3, 2014, 12:45 PM   #49
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Metal God has a good point. Since I started reloading back in the '50's, case headspace has referred to the head to shoulder length on any case headspacing on its shoulder. That includes belted and rimmed cases whose shoulders are far enough away from the case head that the case stops forward movement in the chamber from firing pin impact when their shoulders go hard against the chamber shoulder; the belt or rim doesn't stop against the chamber ridge. New belted and rimmed case rarely, if ever, headspace against their shoulders in SAAMI spec chambers. After firing a normal, max load, most of them will if fired cases are neck only sized. I'm not aware of any gauge that is specifically made to measure the distance from belted case heads to the front of their belt; nor for rimmed cases, either. That's easily measured with ordinary calipers which I've done several times.

RCBS, Hornady and other custom gauges measure this distance on cases showing case headspace from case head to reference diameter on their shoulders. I've got two of the original Arvie R. Martin micrometer headspace gauges for .308 Win and .30-.338 Win Mag made in the '50's by that tool and die maker employed by Sierra Bullets. He made them for Sierra's ballistic tech to measure case headspase on ammo reloaded for accuracy testing. Arvie also sold a few to competitive shooters long before any other die maker made them.

Brian, you're right. The only official "name" for the measurement is an "alpha-numeric character". It's the X with a circle around it in SAAMI's chamber drawings for "headspace." The corresponding measurement on the cartridge drawing has a piramid shaped triangle on that part of the cartridge it its drawing for the "reference diameter." Both can be seen in:

http://www.saami.org/PubResources/CC...pringfield.pdf
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Last edited by Bart B.; April 3, 2014 at 12:58 PM.
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Old April 3, 2014, 01:29 PM   #50
F. Guffey
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Brian, you're right. The only official "name" for the measurement is an "alpha-numeric character". It's the X with a circle around it in SAAMI's chamber drawings for "headspace." The corresponding measurement on the cartridge drawing has a pyramid shaped triangle on that part of the cartridge it its drawing for the "reference diameter." Both can be seen in:
Finally, the circle with the X, something like an old RR crossing sign?

Head space, the circle with the X is used on the chamber drawing, I can only guess it will take years for you reloaders to look for the explanations of symbols used. The symbol for head space is the circle with the X, symbol is absent on the case drawing. The circle , round hole (used to find measure from) has a B, the B is for basic.

Back to the diameter of the round hole does not matter as long as the reolader understands the hole is used as a comparator.

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jwrowland77 Bart, It's funny
and getting funnier.

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