Dies for Bumping Shoulder

[Unclenick]

Yeah, that's like with Hornady and case headspace. I'll guess both were probably driven by one person who uses the term that way and convincing others it is the way to go. I would say SAAMI needs to field some proof-readers, but compliance is voluntary, so they won't.

[HiBC]

Quote:
Originally Posted by HiBC
No one says "blasphemy" when we call it a headspace gauge.
That name is accurate because it refers to a gauge designed to measure chamber headspace indirectly. It measures chamber headspace by making what is called a transfer measurement taken off a case fireformed to fill out to the size of that chambaer. If you read the RCBS PM instructions, it describes determining headspace by measuring a fireformed case. But when you measure a resized case, you are not determining headspace because that case is no longer the size of the chamber.

Quote:
Originally Posted by HiBC
I'm just tired of the folkssaying "Cartridges don't have headspace",etc.
Headspace is the space a case head fits into (or a head and belt or a head and shoulder or a head and case mouth). As far as I know, commercially, the only company in the business to embrace the use of "headspace" as a case dimension, regardless of how it fits in any chamber, is Hornady. The nonsensical aspect is that a head doesn't have to fit inside a case so it doesn't need any headspace in it. What a case does have is a headspace-filling exterior dimension made up of matter (not space) that partially or fully occupies a chamber's headspace depending on how it has been handled. If you want to call that headspace-filling dimension 'case headspace', I don't really mind. My only concern is when people want to know what actual headspace is that they not be misled by the term being used to mean two different things: the size of an empty space and the size of something that typically fills that space only partway. Where both terms appear, that usage distinction has to be deduced from the context, making the meaning of "headspace" implicit rather than explicit. That means more effort is needed to accurately follow the discussion. I don't suppose most people have very much trouble following it, but newbies may, if anybody does. I blame that on Hornady.


Head clearance is not headspace. It is the excess headspace in front of the breech face when the cartridge case is fully forward against its seating surface in the chamber.

Unclenick: You know I have great respect for your knowledge and point of view.

I'll say it once more,then let it go. It seems a waste of time to do so,as I have not seen any response from anyone that indicates they understand what I'm saying.

That probably means my idea is not useful. I'm not the guy who says :"I'm the only reloader…" When "I'm the only" I might be wrong.

Once again,I agree that cartridges do not have headspace This is using the word "Headspace" as a noun.

But the headspace gauge does not have headspace either. The word "headspace" is appropriately used as an adjective to describe the use of the gauge .

Using the same logic,I adamantly do not use the term "headspace" applied to a cartridge case when the word "headspace" is used as a noun.

But a cartridge case does have measurable dimensions. Diameters,angles,lengths.

We can measure rim diameter,call it rim diameter,and communicate. We can talk about case head diameter before and after firing and come up with case head expansion. When I say "head diameter,you know which diameter I'm talking about.


Without saying a case has headspace,I can describe the length of a cartridge case from case head to shoulder reference diameter as "The cartridge case length that we associate with the headspace of the rifle"

I can identify "Which length?" by using the word "Headspace" as an adjective to identify a measurable length in the same way I can use the word "Headspace" as an adjective to identify a gauge.The cartridge case DOES have that length. The argument is over what to call that length when we measure the cartridge case.

No one has provided a useful accepted term. To fill the void,I have provided "Cartridge case length (the noun) modified by the adjective "Headspace"


I also fully understand the term "Head Clearance" I use it. Very often it is the useful term.

Now,I think I will go back to being retired from discussing this topic.

I'm the only one who can choose to stop pounding my head against an anvil.

[Bart B.]

HiBC, how about case "body length" or "body space?"

[HiBC]

I'd be happy with any term we can agree on.
I'd be happy with any term I can use to help a beginner understand the process of setting up dies to a specified minimum head clearance.

I'd be happy with any term that facilitates transitioning a discussion from understanding headspace in the rifle chamber to understanding setting up reloading dies for a specific head clearance.

I want a teaching and communication tool.

I don't have an ego need for it to be the words I choose. For some reason we write a lot because we don't have a term.

I just stepped up and tried to provide one. I gave my reasons why.

If anybody has a better term,by all means! Lets just get this over with.

The thing seems to be,if any of us proposs an idea,its like launching a clay pigeon in front of a Firing Line Forum.

It has toget blasted out of the sky.

But none of the acknowledged experts will step up with a term we can use.

I'd appreciate it if you could train me how to use "body length" to teach a new reloader about setting dies for desired head clearance without using the word "headspace"

I'd be very happy to learn. The anvil is bloody and my head hurts.

[pwc]

This thread reminds me of a similar discussion about cycles and Hertz.

Heinrich Hertz is the guy that discovered the cyclic nature of AC. one positive excursion followed by one negative excursion in a sinusodial wave = 1 cycle. A measurement that has a useful finite meaning.

In the late '60s, someone decided poor Heinrich didn't get the recognition he deserved (probably some liberal) and started a campaign to change cycle to Hertz. Well, they were successful...that's why you zee old radio dials with the frequency in kilocycles (Kc) and new frequency measurements in Hertz (KHz)

Now all this thread discussion is about keeping our brass from stretching just in front of the case head. Caused by the brass moving back to contact the bolt face. Usually ma.nifested by a bright ring around the case.

Others here have been reloading longer than me (35 yrs), but from my beginning, the above condition was stated to be caused by "excessive headspace", the movement of the case head back against the bolt face. That distance between the bolt and case head IS headspace.

Now that description is understandable and has specific meaning. So, this thread can continue to explore freshman Enhlish 101.....for me, I'm going to use the term that most folks understood from the time I began reloading....I'm not going to move from a meaningful name/description like cycle or hesdspace to something abstract as Hz or ????

[Bart B.]

I believe the origin on "excessive headspace" being the cause of case head separation at the case pressure ring refers to chamber headspace. If it's more than 1 or 2 thousandths greater than a rimless bottleneck case head to shoulder reference, the case body's expansion from pressure starting at the shoulder (that's against the chamber shoulder) then working back eventually pushed the case head against the bolt face. Most of the stretching is at the pressure ring because the back 2 tenths inch of the case isn't pressed hard against the chamber wall.

Brass at the pressure ring gets work hardened that weakens from bending during resizing it before other case areas weaken. The more the pressure ring diameter is sized down, the more it work hardens and the fewer expanding and resizing back down cycles can happen before it gets too brittle then cracks the case wall.

Note the case neck length grows about .001 inch per shoot/reload cycle

[Metal god]

Originally Posted by Unclenick

Yeah, that's like with Hornady and case headspace. I'll guess both were probably driven by one person who uses the term that way and convincing others it is the way to go.

The interesting thing in your assumption ( to me ) is that I believe the same thing but the other way around . I'm on many firearm forums and It's pretty clear to me that the vast majority of the posters on those/these forums except the term case headspace and what it has organically and naturally grown to mean over time . As ALL words , terms and phrases are introduced over time in all languages . Not only are new words introduced , old words change there meanings or there meanings expand to mean other things . This is not a new concept . I'm no math buetition but I think this has been going on for thousands of years ????

However there are what appear to be a very small minority of guys/gals on these same forums ( not many really ) hanging on to there belief that language , terms and phases can not change or evolve ( at least not when it comes to firearms ) . I'm sure not all of them but my guess is most are older guys that won't be here much longer in the grand scheme of things and the reloading community will be able to move forward soon enough once they are no longer throwing there wrench in our evolution . I'm sure we all can agree time stands still for no one but some appear to think they can at least slow it down while they're here .

MAYBE this jennie can be put back in the bottle but I don't think it's likely .

It's not often one person or group tells the rest of the world how it's going to be and the world says OK , especially now with social media . Even if SAAMI came up with a term for the casehead to datum point measurement tomorrow . We'd all jump on are keyboards and go to town saying how wrong or right it was . This is why IMHO this debate keeps going on & on . The term case headspace did naturally grow over time and has been widely excepted . I've said it before so I'll say it again . Case headspace is different then headspace because it has case in front of it . It's the very reason it's actually not confusing .

Let me ask you this , can these to sentences have two different meanings ?

I'm going to go check my headspace

I'm going to go check my case headspace .

They are clearly saying two different things . Even if you have no idea what they mean . A reasonable person can clearly see there is something different in those two statements . That same reasonable person can then ask , seeing how they don't know what either means . What's different about those in meaning ? We then as reasonable , experienced reloaders or gunsmiths or what ever then can explain the differences . How and or why is this so confusing ?

I don't know MAYBE we could even explain the evolution of it all to help be more clear rather then staying trapped in our dogma of the past refusing to except what so many already have . I mean if you think I'm ever going to stop using the term case headspace you are mistaken . Not because I think I know better or want to be difficult . No , it's because I've seen so many in our community already understanding the term and excepting it . It's not like I made it up or anything . I think Slamfire ( a member here ) said once , he knows the term case headspace has been being used for decades now . since the 80's I believe maybe longer .

Do you all really think it's going anywhere ? seriously do you ???

[pwc]

No matter what you call IT, the result is the same.

[HiBC]

Metal god:

I think you made a couple of good points. Among shooters lives a certain resistance to change that might be called xenophobia.
Dang percussion caps! Dang smokeless powder!!Dang repeating guns! Dang bolt guns! Dang semi-auto pistols! Dang scopes! Dang free float Model 70's! Dang AR-15 evil black rifles!!

Also true language evolves to meet needs. 10 years ago(+ or -) it was a rare one percenter far enough into Handloading to comprehend a need for ,measuring,and controlling head clearance.

We had no need for the words as tools to communicate ,share and teach such things. Headspace was for gunsmiths .Cranky,crotchety gunsmiths .

Reloaders should just read instructions,take whatever the RCBS 2 die set gave them,and accept scrapping the brass after four loadings.

Unlike some,who believe they are the "keeper of the mysteries and secrets" I'm happy to pass on what I know to anyone who wants to learn,for free.

It seem a silly waste to take it to the grave.

Its tiresome to have to struggle over words. Tiresome enough to say "Screw it. Let them learn from someone else"

Critics are easy to find.

Still no one has stepped up with the term to transition from understanding headspace in the chamber to translating the concept to controlling how we set up the sizing die.

Someone write up a politically correct lesson,make it a sticky,and post it .

Then we can just say "Go read the sticky" and be done with it.

[Bart B.]

HiBC says no one has stepped up with the term to transition from understanding headspace in the chamber to translating the concept to controlling how we set up the sizing die. I understand his concept and reasoning as he explains it. It's how some others think as an internet search for "headspace" will reveal.

I've often suggested we use the full length sizing die's dimension from the standard shellholder face (where the case head rests, .125" below its top) to the die shoulder when they're touching. Call that the die's headspace. All the sizing die companies I've asked all say their full length sizing die's "headspace" is controlled and verified almost exactly like barrel chambers. The difference is sizing die headspace is typically about .005 inch less than SAAMI spec barrel chamber minimum GO headspace gauge; 1.625" for the 308 Win; for example.

Measure your dies to see what their headspace is. How far below the die bottom does a GO headspace gauge head stick out? My 308 Win FL dies make a 1.630" GO gauge stick out about .130 inch. When against a standard shellholder, the shellholder face is 1.625 inch from the die shoulder.

Such dies set in the press to touch the standard shellholder full length size fired cases such that the case shoulder ends up about 1.627" from the case head. That is what SAAMI specs list as minimum case head to shoulder dimension. There's a little metal spring back in the case. Which is a basis for calling that dimension "case headspace."

[Don Fischer]

Anybody know what time the Patriot game comes on today?

[HiBC]

I never really thought of measuring the die.

Good tip! I can work with that.

And I appreciate your comment on "cartridge case headspace" and "reloading die/shellholder headspace"

I agree the relationship between the shellholder and resizing die shoulder are essentially the same as the relationship between the bolt face and the chamber shoulder.,though they may differ slightly dimensionally.
And if we were lawyers,we could argue the reloading die and shellholder ,in the press will have a "reloading headspace",same as a rifle.

In the press,we can tune the "die headspace" to optimize had clearance.

Bingo!!
Bart,a real benefit to what you contributed is IMO,it will make it easier to pass the knowledge on.The images of the bolt face /chamber shoulder and the shellholder/die shoulder will be easy for the new handloader to see.

If a person has a headspace gauge as a standard,measuring the protrusion from the die is as simple as cleaning the die,inserting the headspace gauge (die is hand held) and measuring the overall length of the die body and the gauge protrusion.. Then simply measure the die body and subtract.What remains is the protrusion.

We have enough information to use a feeler gauge or the Redding graduated shellholders to pretty much select a head clearance,subject to verification.

Thanks!!

[Bart B.]

Deleted; off topic!!!

[Bart B.]

HiBC, good to see you've got a decent understanding of case and chamber dimentional relationships regardless of where the chamber is.

[Marco Califo]

The Patriots game comes on right before the first kickoff.
5:20 PST, on the East cost they have to wait until 8:20 EST.

[Unclenick]

HiBC,

OK. Now I'm getting what you are saying. Must have read it too fast before. Apologies.

Originally Posted by Metalgod

I'm going to go check my headspace

I'm going to go check my case headspace.

They are clearly saying two different things .

That's where I get hung up. They aren't necessarily going to be understood to mean different things, especially not if brought up in different circles (say, at a SAAMI meeting) than the forums. That's what got me started looking for a separate term originally, like the one you contributed long ago. Here's an example of them meaning the same thing (this uses "cartridge" instead of "case", but the syntax is the same, so the confusion is possible for both):http://bulletin.accurateshooter.com/...ng-the-basics/

Originally Posted by pwc

Others here have been reloading longer than me (35 yrs), but from my beginning, the above condition was stated to be caused by "excessive headspace", the movement of the case head back against the bolt face. That distance between the bolt and case head IS headspace.

You are skipping a step. You are right that excess headspace causes the problem, but indirectly. Excess headspaces (the chamber being cut unnecessarily deeply by the chamber reamer) is what makes room for the cartridge to move far enough forward to create excess head clearance behind it. If you tip the gun up in the air, the cartridge falls back against the breech face and the excess head clearance disappears, but the chamber's headspace remains unchanged. It's just that now the clearance is out in front of the rim or belt or shoulder or case mouth instead of being behind the head. At that point, it becomes rim clearance, belt clearance, shoulder clearance or case mouth clearance in common parlance.

[Bart B.]

Remember that rim clearance, belt clearance, shoulder clearance or case mouth clearance are reduced to minimum when a bolt face ejector pushes the case forward to some chamber limit. Then some case head clearance to bolt face exists until the firing pin hits the primer. That usually drives the case further forward a thousandth or more before the primer fires.

[Unclenick]

Right. I forgot to exempt guns with spring-loaded ejectors from the tilt-up example. But any fixed ejector guns, a Mauser rifle, a 1911 pistol, a lever gun, et cetera, will be amenable to the elimination of head clearance with upward pointing.

[Metal god]

They aren't necessarily going to be understood to mean different things, especially not if brought up in different circles (say, at a SAAMI meeting) than the forums.

I don't believe for a second you think if someone in a SAAMI meeting said case headspace , everyone would just sit there looking confused . I get it when you say and or think it may be confusing to new guys but the experienced guys know what is being said even if they don't like it . That's because it's been around for a looooong time .

Originally Posted by From link

The actual headspace of any firearm is the distance from the breech face to the point in the chamber that is intended to prevent forward motion of a cartridge.

Yes but we are not talking about a "firearm" and is why it should not be confusing . If you ask me ( which nobody did ) using the word cartridge instead of case is wrong in many ways and is in fact confusing . We can go back to the clip or magazine , bullet or cartridge . I mean IMHO a cartridge really can't be any further away from a case in relation to definition then it could possibly be . A cartridge is a fully assembled " cartridge " . It's not a case or a bullet so when we as "reloaders" reference cartridge head space it seems kind of useless . We are done with it once it becomes a cartridge so cartridge headspace seems irrelevant because you should have known your case headspace well before it becoming a cartridge ??? This is my overall point I guess . As some are nit picking headspace , so can cartridge headspace or bullet/cartridge .

When you hear someone say bullet and they are referring to a cartridge , do you always correct them ? No we don't because we know what they mean and it never results in them only loading a projectile into there chamber and trying to "fire" oops I mean "discharge" it because fire was not originally defined as discharging a weapon so we can't use that word/term anymore when describing what happens when you pull the trigger of a firearm .

I don't know it just seems to me this is only confusing because we continue to make it confusing , it really does not have to be . I know I originally though headspace was the gap/space between the bolt face and cartridge head . If memory serves , I believe it was Unclenick , Bart B and yes Guffey who helped me understand what headspace was . It may have been a tad confusing for a short time but not so much so I was not able to recover haha . I believe I still understand what headspace is and isn't and have not been confused for many years well about headspace anyways . Now headcase is a whole other story

[Bart B.]

Originally Posted by Unclenick

Right. I forgot to exempt guns with spring-loaded ejectors from the tilt-up example. But any fixed ejector guns, a Mauser rifle, a 1911 pistol, a lever gun, et cetera, will be amenable to the elimination of head clearance with upward pointing.

The Mauser style extractors I've had (pre '64 M70 Winchester) typically push the case against the chamber hard enough to keep the case head from falling to the bolt face with the rifle pointed up.

[HiBC]

Metal god:

We're close to being on the same page,but when it comes down to it,what difference does it make if its a cartridge case or a loaded round when it comes to head clearance ? When it matters is when you shoot it,and it will be a loaded round,made from the cartridge case you carefully resized.

Unclenick, Thanks! Its good to be understood.

[pwc]

As reloaders, we are trying to minimize the case stretch back to the bolt face when a cartridge is fired.

Whether the cartridge case shoulder rests against the chamber shoulder, causing space between the cartridge case head and bolt face or the cartridge case head rests against the bolt causing space between the cartridge case shoulder and the chamber shoulder, the result is the same; brass stretch and thinning of the brass just ahead of the cartridge case head.

This thread, way back at the top discussed how to minimize this, thru several ways by different reloaders. I don’t think we can judge between whose is best, although that judgment appears to be desired by some, because for each reloader, their process seems to work for them, and that is the true test of any process; does it meet the needs of the affected person using their equipment. Others who have no process just need to pick one, or all, and try them to see what fits their need.

Now the discussion has gotten sidetracked and has degenerated into what this esoteric “space” is properly called. It seems to be a shape shifter of science fiction. It has been discussed ad nauseum, but it is still there and it is the undesired space that allows the cartridge case to stretch to fit a given barrel chamber / action combination.

I know what my group of shooters calls this “space” when we discuss it and everyone knows what it is. Perhaps what it is called is regional, or maybe even generational as referenced by the fuddy duddy inference.

There is a lot of good information here, I know my process has been somewhat refined by this discussion, but not what we call this “space”. So, now I think I’m going to go do something more productive than continue to follow this thread; maybe like cleaning the lint out of my sock drawer.

[Bart B.]

Personally, I don't want the fired case to completely fill the chamber. Bolts would be harder to open; especially those whose face was never squared up. A few ten-thousandths clearance all around the case is good.

No, the case won't float in space; fired case dimensions are a smidgen less than the chamber. A 20+ pound spring pushes the fired case forward via the firing pin to the chamber limit so there's a tiny amount of head clearance.

[HiBC]

pwc: Perhaps no other topic has generated as much discussion as headspace.

If you would prefer another topic,you are free to start a new thread.

If the topic here bores you,or if you can't relate,or if for any reason at all you would prefer to not read it,by all means go clean your sock drawer.



Have a nice day

[Bart B.]

Other chamber terms that spawns disagreements are freebore, throat and leade.

This forum's list: https://thefiringline.com/library/acro/acron.html is a good example. Scroll down to "Terminology" then to"throat" and see for yourself. Compare them to SAAMI's glossary.

Cartridge names can be misleading. The 38 Special shoots 35 caliber bullets.