Don't stress your press

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.
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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.

F. Guffey
 
I've posted these pics many times in threads talking about this very thing and will again here .
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And you did it all by yourself:rolleyes:

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.

F. Guffey
 
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?
 
Metal god said:
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,
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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.
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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.


StripesDude said:
Semantics arguments are best had by people with nothing better to do.
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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.
 
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
 
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.
 
There's nothing wrong with "cartridge case headspace gauge".
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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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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
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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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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.
 
I looked into the cast iron thing a bit more and am now of an opinion it is probably white cast iron not gray, gray does not make sense design wise. White is more flexible and stronger than gray. That hollow pin though is there for a reason and the only reason I can think of is to allow flex in the linkage to keep from over stressing the frame. That plus just the common sense of knowing there is play in the pivot joints so I would still bet a six pack of beverage that the play is in the linkage not the frame flexing
 
I’ll add if you can say one tool is made by a chamber reamer which makes it legitimate . If another tool is made by the chamber it self by press fit agsinst the chamber walls with 60k psi or pressure, that tool should also be just as legitimate to measure headspace .
 
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To me the test of ammo is what it does at the range. Today I shot a 96% 60 shot aggregate with some ammo that was only half developed, I am pretty darn sure none of the dropped points were due to how I set my case sizing or what I call setting the shoulder back. Cases were on 4th firing with no anneals since factory
 
When the shell holder meets the base of the die, that is it, that's the end, your case cannot be stuffed harder into the die than it already is, it has gone as far as it can, and camming over will do nothing but stretch or compress certain parts of your press by hundredths or thousandths of an inch.

Since the shell base itself is loose in the shell holder, your work is simply done when that shell holder presses up against the mouth of the die.

My press has a pin at the base that prevents cam over.
 
As points of reference, I checked four presses for cam over. Neither a Rockchucker from the 1980s, a Rockchucker from about 2010, nor a Lee Classic Turret from about 2010 cammed over. A Hornady AP Press from about 2013 had a small amount (less than 0.002") of cam over.

Keep in mind that cam over of a press is a feature that is inherent (or lacking) in the press itself, and die adjustment has no bearing on whether a press cams over. That, of course, assumes the term is properly used.

The term can be misused to describe what happens when screwing a die down far enough, and raising the ram high enough, to place the press links and components in a bind such that a deep clunk sound is heard.
 
Been following this from the beginning. I guess I don't understand. My press handle and linkage goes over center. This is how its made. I am sure of that. The die is screwed in so the case is sized properly. If its a carbide pistol die, its not supposed to touch the shell holder. I put the case in, the handle goes down and the ram goes up. The ram reaches its peak height then relaxes the last part of the handle stroke. The handle gets more difficult as the case is sized, then gets real easy at the very end of the stroke.

Over center. If this is what you are calling cam-over, its supposed to be there.


This is my only analogy. When compound bows came out they had cams or offset pulleys. The very first ones you pulled the string. It got harder until about 1/2 the draw length. Then it got easier. It was an over-center design.

The first ones had a stop at the end of the draw. This is how you knew it was at full draw. So you were pulling against a stop. You could pull as hard as you want with no additional change in the draw. This was counterproductive because the idea was to have an easy hold.

I feel once the press linkage has gone over center, its job is done, now return the handle.

Without the over-center design, you can apply a different amount of pressure on each round getting inconsistent results. Over-center assures the exact same ram stroke per handle stroke regardless of how hard you push on it especially once the stroke is complete.

How deep a rifle die is screwed in can make the over-center more difficult. A Point of diminishing returns is reached for the amount the shell is sized. Common sense should step in and if you have to lean on the handle to get it over center, then you are doing something wrong.

David

Sent from my SM-T900 using Tapatalk
 
Talk about a simple task ( reloading ) so confusing . Sizing brass I followed the instructions , knowing the basics , screwing the die down to the shellholder removing the slack between the threads , all made sense so far , removed all movement . What doesn't make sense to me it why go any further , this can't be good for the equipment . That's when I went with the Competition Shellholders , that made sense to me setting up the same way . Press isn't stressed , brass is softer and can be formed with the right tools . What's that saying " the path of least resistance " . Guys , I'm no rocket scientist like some . I don't care the make up of brass or the stress level of steel. All I want to do is size a case the size I want it and find the tools that will do it without over doing things that can cause wear and tare.

PS When I hammer a nail into wood the head stops flush with the board , I'm one of those guys.
 
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.
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I think that is so you can reach through the left pin with a long punch to drive out the right pin.

I once skimmed over the instructions for a Lee Collet Neck Size Die, screwed it WAY down in the Rockchucker, and blew the top plug right out of the die body as the linkage "cammed over." Lee replaced it but with a callout to their instructions not to cam.


The headspace on a .308 chamber is the distance from the bolt face to a .400" datum in the shoulder cone.
Well, looky here, there is also a specification for the distance from the casehead to a .400" datum on the cartridge shoulder. They don't call it "cartridge headspace" but I do because it is fewer words.


If I am loading mixed brass, it is probably not for serious target shooting, so I size the dickens out of it to be sure it all chambers freely. Good enough for plinking, 3-gun, or offhand practice where the target is large.
I am more careful loading same lot number brass for small group/high score.
 
True cam over is what you get when you screw an RCBS die into a RCBS press the specified 1/4 turn.

I don't own any other preses (Junior and two RCs) - but the die mfgs say the same thing (up to 1/4 turn) which I don't do.

I don't do that.
 
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