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Old January 11, 2019, 02:58 PM   #26
Metal god
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How about adjusting the die down/in 2 full turns after touching the shell holder ?? You will not get any cam over no matter how hard you force the arm down correct ??? This is how I adjust my universal decapping die . My press arm only goes down about half of it's potential movement . How about this , thread your die up from the bottom to where you can just barely fit the case into the die . Do you get cam over with the die adjusted this way ?

To be honest I'm not sure what the question is or is about . If you allow for cam over you are not actually creating as much stress on the press as you potentially can in other ways if adjusting the die as described above . I once improperly adjusted a collet neck die then put maximum force on the handle of the press and broke the die because the leverage the press created .

I like cam over with my competition shell holders . It allows me to have a consistent stress factor on my press . These types of shell holders need the die and shell holder to make contact throughout the final sizing process . With light cam over I can consistently have the same amount of stress exerted on the linkage every stroke . If I screw the die down further to avoid cam over I personally am the deciding factor on how much stress my press has to handle . The harder I lean on the arm the more stress my press must deal with . At 6'3" and close to 300lbs I can put some real stress on my press as evidence by me blowing apart my collet neck die . Maybe a little girly man won't stress there press but we are not all built the same . Light pressure to me is like standing on the press arm to my girlfriend .

Then there's the consistency factor in your sized cases from head to datum point . As unclenick and others have pointed out . If you have a variance from head to datum of .002 to .008 and want your bullet just touching the lands . That slop of you cartridge in the chamber is how much your bullet variance to the lands will be each time the firing pin pushes the case fully forward . If your case can only move .002 then that's how much closer your bullet moves to or into the lands . If your case can move .008 in the chamber , that again is how much your bullet is moving forward as well . getting jammed into the lands that same amount .

Making hard contact with the shell holder removes all the press deflection and creates a consistent head to datum point distance . This results in the cartridge moving forward in the chamber the same amount each time the firing pin hits the primer resulting in a consistent ogive to lands variance .

Is cam over necessary , no . Does came over hurt your press , no not necessarily . It's kind of like , does cleaning your firearm hurt it ? Yes if done wrong it will every time .
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Old January 11, 2019, 03:43 PM   #27
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Too bad the definition of “cam over” has been corrupted by so many, including the author of the article in the OP. As a result, threads like this become a source of considerable confusion and misinformation.

Most of the following has already been stated or implied in this thread. But since it's scattered about among considerable garbage, I've summarized it below.

Essentially every press in common use today can be used to suitably size a case. In most instances it's as simple as adjusting the sizing die down as far as needed to do so. If the sizing die adjustment reaches the point where the shellholder contacts the die bottom with a case in the die, screwing the die down further accomplishes nothing beyond further stressing the press. The simplest way to achieve further case sizing (if needed) is with a shim (such as a feeler gauge) between the case head and shelf of the shellholder that normally contacts the bottom of the case head.

As suggested in a post above, adjusting an expanding die or a seating die to contact the shellholder has the potential of reducing variations in case mouth expanding or bullet seating position. Just make sure you don't apply too much pressure to the press arm.
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Old January 11, 2019, 04:25 PM   #28
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Thanks to Unclenick and Mr Guffey we all now know when so called experts use words and terms like this when it comes to reloading
Ok, we are not a bunch of PHDs trying to make a nuclear reactors, we are re-loaders.

I do thank Unclenick for all the good work he does. I don't thank Mr. G because unless you are PHD deep into it, its just confusion and not worth trying to figure out. I had an algebra teacher like that. He failed 80% of his students. The other one passed 80%

I have never presented myself as an expert, I believe knowledge about the job without being arrogant.

So what are you getting that I am not? My bases no longer crack and I don't cam over.

My groups are in the 1/2 inch area. So, with some simple mechanic it works.

As none of us is likely to get a PHD anytime soon (really late in life for me) what does all the tehnco mumbo jumbo jargon do other than make it difficult to figure out? If I understand Quantum physics does that make my reloads better?

I have forgotten all the spin in algebra (they have corollaries about this that and the other hing and makes your head spin) , but boy can I use the formulas I need to this day. Must make me some kind of sub human. Anyone ever use the left handed rule of electron flow?

I can talk all day long about the various fuel injection system on a diesel, no one could give a hoot less, how do you make it work. You put diesel in the tank and turn the switch on.

So, thank you, I will stick with my measure the shoulder, set my press to knock that same shoulder back .003 and life is good.

Oddly, those cartridge fit the gun just fine. Keep it simple, if someone wants to deep dive they can. Most of us don't.

Dang, I must be doing something wrong.

I contend you make it so complicated you do a disservice to a re-loader that all he needs to know is he measure the shoulder, adjust the die to move it back .003 or so and he can go on with life and not wreck his poor brain.

The military has made it simple, they give you instructions, you follow them, the outcome desired is guaranteed. You don't have to know the physics of it.

You start your car, do you need to know what the computer is doing or just put it in gear and it does what its supposed to?

Do you really know how your computer works?

So, it works. If you want the PHD, go for it, me, I don't have that kind of time.
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Old January 11, 2019, 04:29 PM   #29
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I went over an played some more and oversized a few more of those old cases.

Bear in mind that the dies are 7/8 -14 thread so that is just over .007 travel for one full rotation.

I started with the die just contacting the shell holder. Sizing was a predictable 1.623. Another 1/4 turn and it was 1.119 with a cam over effect, 1/2 turn and I got 1.615 and a cam over, 3/4 turn no cam over and measurement between 1.615 and 1.613

My final theory is that when not camming over the resistance of the case is overcoming any play in the linkage pins keeping the shellholder from contacting the die and by the time you get to 3/4 turn the ram linkage has overcame the case resistance.

Anyone have any other theories? There is no slop in the die threads once the locknut is tightened and cast iron is not known for it's flexibility. You are not going to compress steel so that rules that out.

On the linkage theory grab the linkage and you can deflect it laterally and vertically a few thousandths . It is designed with some play in the pins so that it rotates smoothly without binding. That my friends is where I believe the cam over ghost hides which is what I suspected for years but never stopped to take time to investigate
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Old January 11, 2019, 05:55 PM   #30
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Bear in mind that the dies are 1 -14 thread so that is just over .007 travel for one full rotation.
hounddawg: you might want to edit this before someone sees it??
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Old January 11, 2019, 05:56 PM   #31
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Hounddawg:
Quote:
So back to the question" do you need to cam over". Just speaking for myself no, I can get by without stressing my press. Whether you need to is a question only you can answer. If you are running a loose chamber and getting case stretch of .007 maybe you do. It probably also adds to the consistency if you are prone not to not forcing the handle all the way down when operating the press. The little bump in the stroke being a tactile reminder
I think that is what it will always come down to in the final analysis. You find what works best for you using your dies in your press. You are loading what works in your rifle or rifles as the case may be.

Ron
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Old January 11, 2019, 06:24 PM   #32
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hounddawg: you might want to edit this before someone sees it??
thanks 7/8 - 14, I had just divided 1 by 14 to get the .071 number and had 1 stuck in my head

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I think that is what it will always come down to in the final analysis. You find what works best for you using your dies in your press. You are loading what works in your rifle or rifles as the case may be.
Yeah I keep mine really tight, I just bought 100 6CM cases from Alpha. Great cases but the factory resize was way short for me with .005 clearance. After first firing I will only bump em back .002 - 003 from the GO gage measurement
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Old January 11, 2019, 07:04 PM   #33
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14 TPI will give 0.071" of travel per complete turn, 0.018" per 1/4 turn, 0.036" per 1/2 turn, and 0.054" for 3/4 turn.
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Old January 11, 2019, 08:31 PM   #34
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I started with the die just contacting the shell holder. Sizing was a predictable 1.623.
I would bet not , Was it for the few cases used that likely had same head stamped and same number of firings , Sure . Now run that same test but this time use Winchester cases Lapua cases and LC cases all with different amounts of firings/ work hardenings . See if your head to datum point measurement is as predictable now .

I can tell you it won't because I ran that very test 5 years ago and my case head space measurements were all over the place depending on the manufacture of the case and how many times it had been fired . It also changed if the cases were freshly annealed . resulting in me constantly needing to readjust my die to only bump my shoulder back .002 .

I've posted these pics many times in threads talking about this very thing and will again here .

Here is the die set up exactly as you described , screwed down to where it's just touching the shell holder when not sizing a case . Keeping in mind that this position is in cam over so the shell holder is actually pulled away a little yet still touching .



Here is that same setting sizing a 308 case . As you can see the flex in the press and linkage has now allowed a gap to form between the die and shell holder when sizing the case .



I don't remember the exact gap size but know it was at least .008 . Meaning sizing that case with that amount of firings my press deflects .008 . A freshly annealed case may only cause the press to deflect .004 . Meaning if I keep my die set the same in the press depending on the cases I'm sizing there can be an variance of .004 from head to datum . So if I'm only trying to bump a shoulder back .002 on a case that deflects my press by .008 I won't bump the shoulder at all and will need to re adjust the die .Or place a feeler gauge under the case in the shell holder



Which is incredibly time consuming because you have to measure every case every time you size it to know what size feeler gauge to use . This is why I use the Redding competition shell holders . They are designed to have the die and shell holder make contact removing all that press flex . Actually what they do is force the press to flex past what your case can make it flex resulting in a very consistently sized case from head to datum point because the press is over powering the cases ability to spring back .
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Old January 11, 2019, 10:08 PM   #35
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I am not interested in ruining any Lapua or Alpha brass, those Hornadys was range pickup where a guy was sighting in his hunting rifle and was not a reloader. I just wanted to see where the flex was and now I know. It was entertaining but I have had quite enough of dial indicators and feeler gages for awhile

Thinking about it though I would guess the difference between brands would be due to the properties of the brass. I would also guess changing presses would change readings also. The less flex in the linkage the less of a gap, more leverage would also result in the same.

Bottom line is I have my dies set where I want them and do not need to stress the linkage. I use .002 - .003 setback, rounds always chamber and I get long case life and that makes me happy
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Old January 11, 2019, 11:54 PM   #36
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Thinking about it though I would guess the difference between brands would be due to the properties of the brass.
Correct , to include wall thickness as a factor on how easy or hard the case is to size . It's why I suggested test Winchester cases . In 308 they are my lightest cases by 10+ grains which means thinner walls then the rest .

Quote:
I would also guess changing presses would change readings also. The less flex in the linkage the less of a gap, more leverage would also result in the same.
Yep , and I think my Hornady press has more flex then others if not most others .

Also the slickness of the lube you're using can effect press flex .
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Old January 12, 2019, 07:19 AM   #37
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Too bad the definition of “cam over” has been corrupted by so many, including the author of the article in the OP. As a result, threads like this become a source of considerable confusion and misinformation.
Cam-over in torque wrenches are pretty much like pushing a weight over a peak then when you force is at its zenith it goes over the peak and input force drops.

It’s not an uncommon concept lots of things use the cam overcenter concept.

https://www.rockler.com/cam-clamp?si...SABEgKJvPD_BwE

In a press the idea is a little more handle travel would get you to the same ram/die position (minus stretch & linkage takeup) vs a positive stop where the operator might not hit the stop.

From the OP’s link.

Quote:
Here’s camming linkage and its effect. On left is the maximum height attained by the ram; on right is the ram position at the full-limit stop on the press handle. It’s 0.020 inches on this press.
That is cam-over and as the press was designed the only way to not cam-over is to not make a full stroke. You can run it empty or run a die down and put it in a bind but both will still cam over if you can complete a full stroke.
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Old January 12, 2019, 09:19 AM   #38
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I've been using Wilson Case Gages for the last 50+ years to adjust my sizing dies. I have dies made by Lyman, Herters, RCBS, Dillon & Lee, plus shell holders from all of these manuf.'s. Using the Wilson gage allows me to use most any shell holder with any of these dies. The Wilson gage also shows when a case should be trimmed and by how much. They're well worth the money.

Lastly, blythely, screwing a sizing die down to contact the raised ram/shell holder, plus an 1/8 to 1/4 more will not work with all cartridges, RCBS' instructions notwithstanding. Several of my lever actions, for instance, have overly long chambers (long in headspace), and require longer cases than what is indicated by the case gage, in order to prevent head separation. In these rifles, I size to the extent that I can chamber the case, and feel just the slightest bit of resistance as the lever closes. This is sizing to meet a specific gun's needs. Here's Wilson's description of their case gage.

https://lewilson.com/case-gage/

YMMV, Rod
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Old January 12, 2019, 09:26 AM   #39
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My Rockchucker has a positive stop. It's a lag bolt screwed into the table that stops the press lever just short of full stroke. Without ever hearing of "cam over", it was put there to keep from stressing the press linkage too far at it's furtherest down stroke. There is still flex, as when a die is turned down against the shell holder, then after a case is inserted the die/shell holder has a gap. Depending on need, that gap can be reduced/eliminated by turning down the die slightly. An example of this is to ensure that semi-auto pistol cases are sized as far down as possible. Another example is sizing down a rifle case fired in Military spec chamber down to fit in a tighter chamber. Reloading for differing styles of firearms/brands of brass, the sizing die is adjusted each time.

All these years never really understood "cam over", and still not sure. It sounds like an option some use.
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Old January 12, 2019, 01:03 PM   #40
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Bottom line is I have my dies set where I want them and do not need to stress the linkage. I use .002 - .003 setback, rounds always chamber and I get long case life and that makes me happy
Ditto
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Old January 12, 2019, 01:19 PM   #41
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I think that is what it will always come down to in the final analysis. You find what works best for you using your dies in your press. You are loading what works in your rifle or rifles as the case may be.
When I want immediate neighborhood acceptance I mow my lawn or my wife paus someone to mow the lawn.

When I want immediate acceptance on a reloading forum I agree with reloaders that make this stuff up. Again, I can not find where SAAMI list case head space on their case drawings. I have found their listing for head space in their chamber drawings. And then there was that time I was reported to RCBS as being the one that said my Rock Chuckers do not cam over. Before the employees at RCBS became reloaders I contacted them about the press design of the Piggy Back and Piggy Back 11 attachments for the Rock Chucker. The question had to do with the auto advance meaning the shell holder would only advance in one direction. I had one that would allow the shell plate to advance and rotate in the opposite direction.

MEANING! The piggy back attachment will not work on a cam over press; therefore the Rock Chucker is not a cam over press because the ram does not bump when the ram is raised, if the ram reverses while attached to a Piggy Back 11 attachment the one way clutch will lock-up like a one way clutch in an automatic transmission.

There is no way a press can operate correctly when the cam over press is adjusted like a non cam over press. (To agree with those that make this stuff up) To be accepted the reloader must start by saying "I BUMP....", It is impossible to size a case with a die that does not have case body support; all of my full length sizing dies have bull body support meaning it is impossible to move the shoulder back when full length sizing; but reloaders inisist they move the shoulder back when returning a case to minimum length/full length sizing.

It is possible to shorten the distance from the shoulder to the case head when sizing but the shoulder does not move back. For me it is a big conflict to agree.

And again there are shims. I have been accused of voo-doo reloading on the shooters forum and the high road by moderators that are now claiming and recommending voo doo methods and or techniques. One of them on the shooters broke into a routine that started with; "no biggie...." and then did a cut and paste of one of my responses that he deleted.

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Old January 12, 2019, 01:43 PM   #42
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I've posted these pics many times in threads talking about this very thing and will again here .
And you did it all by yourself

But in the big inning measuring the gap between the bottom of the die and shell holder was a technique to determine if the case had more resistance to sizing than the press, die and lube could overcome. The next time you take credit remind reloaders the press was adjusted to the shell holder with an additional 1/4 turn (that was back when every reloader knew the instructions instructed the reloaders the non cam over press was adjusted differently than the cam over press. I have shared the instructions with other members of this forum, the date if printing on the instructions go back to 1962 and before. The company that printed the instructions were making bullets in 1954 and the best way to get a job with that company was to check the application 'yes' when asked if you could make a reamer.

And then? I suggested using feeler gages when adjusting the die to size cases. You were not there, I know you were not there because you never spoke up on my behalf.

The feeler gage is still more than the reloader can deal with. I noticed on another forum a moderator is using valve spring shims. If I did that I would give Skip's shims credit. I was the one that suggested Skip's Shims were not necessary, I also suggested Redding with their competition shell holders are not necessary. I claimed I could size cases for long chambers and short chambers and cases to length from the shoulder to the case head in thousandths with nothing more than a mechanics/machinist feeler gage set.

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Old January 12, 2019, 05:14 PM   #43
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Guffey - I’ve been dying to ask, how’s your shooting? I don’t post a lot on here as I can’t stand getting into the semantics arguments you and others get into. I don’t care if people use the word “bump” to refer to shortening the length of a case. I don’t care if “headspace” is used to describe something that doesn’t appear as such in Saami drawings. Semantics arguments are best had by people with nothing better to do. But I read almost everything posted (and am often amused).
Your knowledge of reloading, mechanics, and machining terms seems vast, but does that result in extraordinarily accurate shooting?

To me, that’s what this is all about. Someone can create the most perfect round, with the perfectly set up press, with the greatest case prep around. What happens at the range, or during the hunt though?
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Old January 12, 2019, 05:58 PM   #44
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Originally Posted by Metal god
Quote:
Going over the previous material on using a cartridge case headspace gage to determine sizing die positioning to get the correct amount of case shoulder setback,
Thanks to Unclenick and Mr Guffey all now know when so called experts use words and terms like this when it comes to reloading. They clearly don't know what they are talking about.
There's nothing wrong with "cartridge case headspace gauge". It's a gauge made with headspace to accommodate a cartridge to check it for chamber fit. You just have to avoid confusing cartridge headspace with "case headspace". This article at Accurate Shooter defines the former. But if you were thinking the two terms are synonymous, as I infer from the above sarcasm, then you have inadvertently provided an example of the very confusion I would like to find a way to avoid.


Quote:
Originally Posted by StripesDude
Semantics arguments are best had by people with nothing better to do.
That's only true if "everyone knows what you mean". This confusion about the meaning of Cartridge Headspace illustrates that is not always safe to assume. The objective of definitions is to keep everyone on the same page for accurate communication of ideas, not semantics for their own sake. That would be for a linguistics forum.


David,

That's curious about your cam-over presses. Mr. Guffey says his Rockchuckers don't cam-over, but you and Glen Zediker say yours do. I don't own green machine, so I don't know from personal experience, but I do know my Dillons do not cam-over and my Co-ax and Lee Classic Cast and Lee Challenger and my Lee Handtools don't either. The only press I have that does cam-over is my ancient Lyman Spar-T press.

Tangolima has it right. "Cam-over" is just short for 'camming up-and-over the limit of the stroke'. On all those presses of mine except the Lyman, the handle stops against a tab or part of the frame or linkage before it can reach or pass what would be the top of the stroke were the stop not there. You can tell by watching the press ram. As you depress the handle, the ram goes up and is still going up when the handle meets the stop. With the Lyman press, the handle is still moving when the ram reaches the top of its stroke and then descends a fraction of an inch before the handle meets its stop. That's camming-over. It is why Zediker's test in his next-to-last paragraph proves it.

Glen Zediker initially described cam-over correctly in his third paragraph, assuming his Rockchucker is somehow different from Mr. Guffey's several copies. However, he did a disservice by going on to provide a second definition which is really just applying an undefined excess of force to the mouth of the die with the press. That doesn't require cam-over; just enough force on the handle.

When you apply force with the press ram against a die, the press stretches. That's perfectly OK as long as the stretch is within what is called the true elastic limit of the press frame material. Within that limit, by definition, the frame always returns 100% to its original shape when the press ram is withdrawn. Once you exceed the true elastic limit, you incur some degree of permanent plastic deformation of the press. It can be a tiny bit so small it never adds up to anything important over your lifetime, or it can be so gross an overload it not only passes the defined yield point of the material (where 0.2% permanent deformation occurs), it goes on to pass the ultimate yield point, which is where the frame breaks.

On another forum, there was a fellow who broke two RCBS Rock Chuckers. His cases weren't getting as small as he wanted, so he just kept turning the die in further and further and putting more and more of his self-described linebacker-size heft and strength into it until the frame broke. He had pictures. RCBS replaced them both times.

It is apparent that what Zediker is hoping to prevent is press overloading; people permanently deforming or breaking their presses with excessive ram force. It certainly doesn't require cam-over to make that happen. Cam-over just makes it a lot easier to do because of the point of infinite mechanical advantage the linkage passes through at top dead center. But as long as you stay within the true elastic limit of the press frame, be it cast iron or aluminum, no damage will result.

The general instructions for setting up a die with the extra eighth of a turn or so (twice that for an aluminum press due to its lower elastic modulus) are expected to stay within the press's true elastic limit. The reason for it is shown clearly by Metal god's photos. It's that crack of light that appears due to the resizing force already stretching the press frame beyond the length it had when you screwed the die into contact with the shell holder. Zediker is wrong if he thinks all press stretching can be avoided by eliminating interference contact between the shell holder and die. The Lee help video for setting up sizing on one of their single-stage presses describes this at the end, as well.

Zediker gives the example of a die that made a new case -0.008" shorter. Not all dies will do that. I'm not sure I own any that do. He seems to be working on the assumption your chamber is longer than SAAMI minimum and you will, therefore, always resize enough to chamber in your own gun before the shell holder goes all the way into the die mouth, and that is patently not guaranteed. Indeed, failure to do so is the problem the fellow who broke two of the presses was having. He needed the feeler gauge Metal god illustrated (an idea Mr. Guffey first brought to the attention of the forum, AFAIK), but the press breaker didn't know about that.

The other problem with Zediker's thinking was already described. It is when you have cases of mixed hardness that don't all resize the same amount in the same die with the same amount of ram pressure. Once you have the die adjusted so no crack of light appears with any of your cases, you have ensured the resistance of the brass in the die cannot overcome the press position (make a crack of light) and you don't need to turn the dies in any further. That will get as much resizing consistency as your press is capable of in a single stroke resizing operation. It is the reason Redding came up with their Competition Shell Holders.
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Old January 12, 2019, 05:59 PM   #45
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Slightly off topic but as a matter of my own curiosity how much force can the ram on a general purpose reloading press exert? I have read that on most single stage presses the ratio of force between ram and handle is about 8 to 1. What I am curious about is if for example I run my ram to the top of stroke, then back down the ram and add lets say 1/8 turn to my die and run the ram up again how much force I can expect. I know this is subjective and it will vary by press configuration so all I want is a good estimate. Something like pounds of force or newtons if that works for you.

I do know JMorris did some testing along these lines but never saw what, if any, results he managed to get. Does anyone have any ideas on this?

Thank You
Ron
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Old January 12, 2019, 06:12 PM   #46
Unclenick
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In any compound or orbital linkage, it will vary with the position of the handle, becoming greater as you approach the end of the stroke. As already mentioned, with a cam-over press it becomes ∞ to 1 right at the top of the ram position.
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Old January 12, 2019, 06:36 PM   #47
Metal god
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There's nothing wrong with "cartridge case headspace gauge".
No I don't except your premise . You guys have made it quite clear the cartridge nor the case have headspace . OMG what you just did was so hypocritical . You don't get to add words in front of a preexisting word or after then make up a new definition for it while saying nobody else can do the same . What word god did you speak with that said this is ok . Seriously who cam up with the term "cartridge case head space gauge " ??? I'm assuming you are claiming SAAMI came up with that term and not the maker of that product . You guys have made it quite clear that manufactures don't get to make up names to things that use preexist words SAAMI uses for something else and has not approved of the new use . So how did that phrasing come about ? Sure would hate to think it was just the industry excepting it because that would mean case headspace must be excepted , The industry has clearly excepted it as well .

How you think cartridge case headspace gauge if fine to use but case headspace gauge is not is mind boggling to me . Are we not using the Hornady headspace gauge to measure our fire formed cases . Last I checked are fire formed cases pretty much mirror our chambers headspace . So by measuring our fired cases we are basically measuring that firearms headspace . So why can't that gauge be called a case headspace gauge ? You are measuring the case to get your chambers headspace .

Are there other ways of measuring headspace , sure . Are there better was of measuring head space , yes . hmm but are those others the only way ? Before anyone starts talking radius this or caliper flex that . The point is not the design quality of the tool , Not all tools are designed to the same standard as others .
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Old January 12, 2019, 08:27 PM   #48
hounddawg
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Quote:
the reason for it is shown clearly by Metal god's photos. It's that crack of light that appears due to the resizing force already stretching the press frame
if the press is standard (gray) cast iron it will neither stretch or bend even .001 without breaking. That is just the nature of cast iron, tough and rigid as heck. My opinion is any stretch or flex on a press will occur in the linkage at the pivot points. Probably a free or close running fit tolerance on the holes and pins. The two linkage arms on a RC are held on by nylok nuts. The top left arm pin is a hollow pin, I wonder if that is the weak link and designed to flex when x amount of stress is put on the frame to prevent it breaking.

But the main point is cast iron is not renowned for its flexibility or ductility
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Old January 12, 2019, 08:47 PM   #49
zeke
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https://www.engineeringtoolbox.com/y...lus-d_773.html

Not sure if the modulus of elasticity is relevant, but here is a link that compares grey cast iron to other metals.
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Old January 12, 2019, 08:57 PM   #50
reynolds357
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Calming over in a press designed to do so is not "stressing the press." Setting the sizing die too low and calming over stresses the press.
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