squaring dies
- Thread starter zeke
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Apparently there is a magical shellholder with the ability to adjust itself (and the case) to an off vertical die. Does this imply the shellholder, while under the force of the brass being formed, isn't actually flat (bottomed out) in the ram? Does the shell holders ability to slide laterally allow it to align on a vertical axis? Or does this thinking imply the coarse threads on the die automatically (magically) allow the die to aligned vertically each time the locking rings are tightened?
The squaring of dies is not a new concept. Nor do all dies have a perfectly aligned chamber boring.
The squaring of dies is not a new concept. Nor do all dies have a perfectly aligned chamber boring.
No magic. It's just the way the way it works. The dies design does the aligning, the shellholder simply holds the case more or less vertical and allows it to slide laterally to align itself to the die. Dies are cone shaped where the case enters, the side of the case hits the side of the cone and slide in the shellholder when it encounters resistance. As the case slides up and into the die it becomes perfectly aligned with the bore of the die, it it did not it would be damaged by the press and die. That is why shellholders allow float and in co ax presses the dies are floating as well as the cases in the shellholder float
A round sliding from the magazine into the chamber is something we should all be able to visualize. The bolt simply provides the forward momentum like a ram, the case aligns to the bore as it slides into the chamber the same as the case aligns to the bore of the die as it is pushed in by the ram. Same principle except the case is vertical on the press and horizontal on the gun. You can also look at a revolvers design. Before the bullet enters the barrel it enters a forcing cone as it leaves the cylinder to allow it to align itself to the bore in case the cylinder is not perfectly timed to the barrel
when a case enters a die it has two choices, align or be damaged. That case is going to be perfectly aligned with the die when it is all the way in, it has no other alternative other than be crushed
sorry Nick but respect need to be earned. I have a ton of respect for 99% of the people here. Those who come here to discuss, learn and teach others. Posting gibberish and self aggrandizing posts only confuse the new guys and gals and could cause someone to hurt themselves or others or make them just give up on the hobby.
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"Dies are cone shaped where the case enters, the side of the case hits the side of the cone and slide in the shellholder when it encounters resistance. As the case slides up and into the die it becomes perfectly aligned with the bore of the die, it it did not it would be damaged by the press and die."
Thank you for making the point. If the die is locked down and not "squared" to the vertical force of the ram, the case conforms to the bore of the die. If the bore of the die is off vertical slightly, the case is forced to conform to it. This is the reason "squaring" the die, or more directly the bore of the die, can help. This helps in "squaring" the bore of the die to the vertical force of the ram. Squaring the die is not the same as allowing the case holder and case to adjust laterally slightly to self center the case into the die.
If it helps, visualize this as the bore of the die being a vertical line, and the flat bottom of the case as a horizontal line. Squaring the die helps ensure the vertical line is at 90 degrees to the horizontal line.
This was learned the first time i bought a carbide pistol die, with a tilted carbide ring. Have seen this written up as using flat washers on the top of the shell holder to force the bottom of the die into the same plane as the top of the shell holder, before locking the die down. This was explained as keeping the die straight to overcome the possible effects of the coarse threads used on the die and press.
Maybe some would earn some respect if they could politely comment, without resorting to ridiculous analogies. Nobody knows everything, and some have been around alot longer than others. As a very wise person once said, "In order to learn something, first you have to admit you don't know it"
Thank you for making the point. If the die is locked down and not "squared" to the vertical force of the ram, the case conforms to the bore of the die. If the bore of the die is off vertical slightly, the case is forced to conform to it. This is the reason "squaring" the die, or more directly the bore of the die, can help. This helps in "squaring" the bore of the die to the vertical force of the ram. Squaring the die is not the same as allowing the case holder and case to adjust laterally slightly to self center the case into the die.
If it helps, visualize this as the bore of the die being a vertical line, and the flat bottom of the case as a horizontal line. Squaring the die helps ensure the vertical line is at 90 degrees to the horizontal line.
This was learned the first time i bought a carbide pistol die, with a tilted carbide ring. Have seen this written up as using flat washers on the top of the shell holder to force the bottom of the die into the same plane as the top of the shell holder, before locking the die down. This was explained as keeping the die straight to overcome the possible effects of the coarse threads used on the die and press.
Maybe some would earn some respect if they could politely comment, without resorting to ridiculous analogies. Nobody knows everything, and some have been around alot longer than others. As a very wise person once said, "In order to learn something, first you have to admit you don't know it"
so Zeke in a Forster Coax with where not only does the shell holder allow the case to float but also the dies is in a slide in die holder what do you align?
Take a FL sizing die in you hand and slide a case into it. Try doing it at a angle or slightly off center and see what happens, either the case aligns or it does not go in. This isn't rocket science.
In the case of the carbide ring the parts of the die itself were misaligned and locked rigidly in place. Same thing would happen if the case was held completely rigid and you tried to force it into a sizing die that was not floating. The brass will give way before the steel does
What about that revolver bullet entering the forcing cone of a slightly off time revolver.
Are your rounds leaving the magazine perfectly aligned when the bolt pushes them out and into the chamber? I don't think so. As they enter the chamber the shape of the bullet and case guides the round into alignment with the bore.
It's pretty simple to demonstrate for yourself, get a die and a case and try to hold the die and case at a angle and slide the die up into the case.
Take a FL sizing die in you hand and slide a case into it. Try doing it at a angle or slightly off center and see what happens, either the case aligns or it does not go in. This isn't rocket science.
In the case of the carbide ring the parts of the die itself were misaligned and locked rigidly in place. Same thing would happen if the case was held completely rigid and you tried to force it into a sizing die that was not floating. The brass will give way before the steel does
What about that revolver bullet entering the forcing cone of a slightly off time revolver.
Are your rounds leaving the magazine perfectly aligned when the bolt pushes them out and into the chamber? I don't think so. As they enter the chamber the shape of the bullet and case guides the round into alignment with the bore.
It's pretty simple to demonstrate for yourself, get a die and a case and try to hold the die and case at a angle and slide the die up into the case.
This reminds me of Johnny Carson and Ed. McMann; that is not quite everything there is to know about 'the shell holder. From the big-inning I have said my favorite shell holder is the RCBS shell holder because they fit like a hand me down shirt. I am from a family of 10 children; I know how a hand me down shirt fits, if it touches, it fits.
And then there are the advantages of a loose shell holder: I am a case former, the loose shell holder allows me to increase and or decrease the length of the case from the shoulder to the case head. the loose fitting shell holder allows me to increase the presses ability to overcome the cases ability to resist sizing, the loose shell holder allows me to size cases for short chambers and long chambers.
And then there are small base dies; I can use a loose shell holder with a feeler gage to duplicate the effect of small base dies. Some find it necessary to purchase Redding Competition shell holders. There was a time before the Redding Competition shell holder. Back then I used feeler gages to increases and or decrease the deck height of the shell holder; (meaning) I could increase and or decrease the distance from the deck of the shell holder to the shoulder of the die. I understand I have to explain: I sized cases for long chambers and I sized cases for short chambers with one loose fitting shell holders and 'the feeler gage'.
If there are loose fitting shell holders there are tight fitting shell holders; if the loose fitting shell holder has advantages the tight fitting shell holder has advantages. I have both tight and loose fitting shell holders. I have three different RCBS shell holder sets, all three are different.
So you though that was everything there was to know about 'the shell holder?
I made a tool that was similar to a portable alignment tool, I stuck it into a Rock Chucker and then raised the ram; the tool could not be pulled out. I could say it was like a reloader examining hot horse shoes. It does not take a reloader all day to figure the shores shoes are hot.
Straight away I knew the Rock Chucker was not a cam over press and I knew it was in a big time bind. All I had to do was turn the press upside down or crawl under the bench to determine the Rock Chucker was in a bind.
I have at least 15 presses that are cam over presses, for me? It is so simple to measure the amount of cam over.
F. Guffey
The last RCBS press I used that cammed over was the A2. It had .017" cam over. The last person to owned it just died last summer. One day he called to inform me his A2 was locked up' he said he raised the ram and then adjusted the die with an additional 1/2 turn. after contact.
I arrived and suggested we screw the die our first and or use a cheater on the press handle. He was trying to form wildcat cases for a pile of bench rester rifles he built.
F. Guffey
I arrived and suggested we screw the die our first and or use a cheater on the press handle. He was trying to form wildcat cases for a pile of bench rester rifles he built.
F. Guffey
Personally, I don't think this is an issue and since most press frames are probably "line bored" I doubt if there is any problems. If I needed my ammo the hold .0005" concentricity, I might be concerned, but I have taken care of all the worry about dies lining up with shell holders, I bought a Co-Ax. And yep, there is a phenomenon commonly called "tolerance stacking", as Unclenick mentioned. If a part is on the "low side" of a mfg tolerance, and the hole it goes in is on the "high side", then it may be a sloppy fit...
But when stacking it all falls apart when the reloader insist the Rock Chucker is a cam over press. It is impossible to do all that stacking when it is impossible to get the reloader to take their hands off of the key board. One reloader did make a video of a rock chucker being put through its paces. He wasted his time because his complaint was about the forward movement of the ram at the tip when the ram bottomed out. No one understood what they were looking at, it should have been obvious if the ram is kicked forward at the top the ram would be kicked back at the bottom; I do not care about how it is stacked the ram was in a bind and under those circumstances alignment between the ram and press was impossible.
And I always ask when someone claims their press camms over' by how much? I can measure cam over on a cam over press in thousandths. On presses that do not cam over I can measure deflection in thousandths also.
don't know about everyone else's press but the ram on my Rockchucker's ram is encased inside the frame with a sliding fit for four inches of it's travel. If you want to go technical it is a t24 H7/G6 sliding fit under the ANSI standards. In layman's terms that means at full extension on the ram I can deflect the ram .007 measured on a dial indicator mounted to the frame with a magnetic base. If the tolerance was any tighter the ram could bind with temperature fluctuations
if designing your own press you could get by with a H8/f7 or if you want to get anal go up to a H8/H7. But since a ram does nothing except supply a upward force on the case it really isn't critical how much lateral play it has
if designing your own press you could get by with a H8/f7 or if you want to get anal go up to a H8/H7. But since a ram does nothing except supply a upward force on the case it really isn't critical how much lateral play it has
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"Cam over" means nothing except the ram goes up and comes back down. Exactly the same as "over top dead center" in an engine. I cannot understand how this could benefit a reloader. The case will only go so far into the die. whether the ram goes up then down a little, there is only so much a case can enter a die. Perhaps it's the mechanically challenged that want/need a "cam over" over a dead stop?
I have been a machinist/mechanic since 1966, and was a teacher's aid in Metal Shop and Drafting classes 3 years in high school before that and can see no logic in "cam over" being of any benefit...
Arguing over this defect in a reloading press is just silly...
I have been a machinist/mechanic since 1966, and was a teacher's aid in Metal Shop and Drafting classes 3 years in high school before that and can see no logic in "cam over" being of any benefit...
Arguing over this defect in a reloading press is just silly...
It was not silly when RCBS printed the instructions for both presses meaning when adjusting a press the cam over press is adjusted differently than a non cam over press. And then! I said: He locked his press, he could not lower the ram, and then he called me. He had one foot up against the bench and both hands on the handle and with all of his effort he could not lower the ram.
I suggested we screw the die out or place aa cheater on the handle because I knew the ram would not lower until he raised it .017". He crammed his press over and then went it into the leaver lock mode .037" because he lowered the die 1/2 turn because the case refused to be sized.
What is it that you do not understand after all of these years? Bump! The cam over press is a bump press, to understand the bump press is to adjust the press die when the bottom of the die contacts the shell holder. Try to remember the bump press bumps twice, it bumps on the way up and again on the way down. If the die is adjusted after the ram bumps the amount of sizing must be added to the amount of cam over.
So 1/4 turn on a non cam over press is .017"; but 1/4 turn on a cam over press can be .017" plus cam over. Back to the A2, it had .017" cam over, my friend lowered the die 1/2 turn, I am surprised sparks did not fly from the press.
mikld, I believe you are catching on, I do believe there are more mature ways to handle it.
F. Guffey
Mr. Guffy. I believe the "cam over" was probably a defect discovered by reloaders long ago and the press manufacturer just as a CYA measure, touted the action as "new and improved". I'm surprised that you mention "mature" as you are well know as one who will argue almost anything and be insulting too...
50 years reloading and have never read or seen anything on " squaring dies"....
This sounds like something an internet expert has devised as a most necessary thing to do to load proper ammo.
I don't pay much mind to the internet experts requirements.
I screw the dies into the press and reload with them.
Gary
This sounds like something an internet expert has devised as a most necessary thing to do to load proper ammo.
I don't pay much mind to the internet experts requirements.
I screw the dies into the press and reload with them.
Gary
And if you were not so wildly indignant about everything I post you would know that is not true. I said I shared instructions from a manufacturer of presses that covered presses with members of this forum. Cam over is a design, again, this stuff does not drive me to the curb.
Again, when adjusting the press it makes a difference if the press is a cam over or non cam over press. I have had members report me to RCBS as being that mean ol' guy that claims the Rock Chucker is not a cam over press.
F. Guffey
When setting up dies on my one and only the RCBS RockChucker Supreme . I screw the die down to meet the shellholder to remove the slack from the threads and that's it . Worrying about press alignment its just another thing to drive yourself crazy . Reloading has enough twists and turns without adding another .
https://sierrabulletsblog.com/2014/02/12/lack-of-concentricity/
https://www.google.com/search?q=sie...69i57j69i60.8996j1j7&sourceid=chrome&ie=UTF-8
Just a slight rehash of what they used to have in their tips section.
https://www.google.com/search?q=sie...69i57j69i60.8996j1j7&sourceid=chrome&ie=UTF-8
Just a slight rehash of what they used to have in their tips section.
I have two questions regarding statements in this article
How do you square something that has no adjustments? On a normal press the dies is screwed down into the top strap of the press, the locknut will screw down flush with the topstrap unless you are using a O ring underneath.
The bottom of the shellholder is going to sit flat on the top of the ram. I can just slip in a .014 feeler gage between the bottom of the shellholder but if the ram's top surface is square to the presses topstrap the die will be square when screwed in and the locknut tightened. The die has no choice on whether it is square or not and there are no adjustments anywhere on press to adjust tilt of the ram or the die
The case sitting in the caseholder has another .013 or .014 clearance between the bottom of the case and the top of the shellholder.
the other part that leaves me wondering is this
allowing the die to free float as well as the case in the shellholder to free float accomplishes exactly what except more room for play as the case aligns itself to the die.
You can give the die some float on any press if you use a O ring between the die and the locknut like the Lee locknuts do. I don't bother with them myself figuring any misalignment will be taken up by the float in the shell holder
There is so much BS floating around on the internet from so called experts it is amazing. Anyone who doubts any of what I just posted take a case slid it as far into a sizing die as possible with your fingers and the see if you can tilt it even .001 degrees out of alignment when it is inserted into that sizing die. have fun because you can bend the case at the webbing you are not going to move it. Then slide the case into a shellholder and slide it in that die, uou can see the play between the case holder and the die but there is exactly 0 (zero) play between the sizing die and the case because the walls of the case conforms perfectly to the walls of the die. That is the purpose of having play in the shellholder and with some lockrings and presses play between the die and the press
How do you square something that has no adjustments? On a normal press the dies is screwed down into the top strap of the press, the locknut will screw down flush with the topstrap unless you are using a O ring underneath.
The bottom of the shellholder is going to sit flat on the top of the ram. I can just slip in a .014 feeler gage between the bottom of the shellholder but if the ram's top surface is square to the presses topstrap the die will be square when screwed in and the locknut tightened. The die has no choice on whether it is square or not and there are no adjustments anywhere on press to adjust tilt of the ram or the die
The case sitting in the caseholder has another .013 or .014 clearance between the bottom of the case and the top of the shellholder.
the other part that leaves me wondering is this
allowing the die to free float as well as the case in the shellholder to free float accomplishes exactly what except more room for play as the case aligns itself to the die.
You can give the die some float on any press if you use a O ring between the die and the locknut like the Lee locknuts do. I don't bother with them myself figuring any misalignment will be taken up by the float in the shell holder
There is so much BS floating around on the internet from so called experts it is amazing. Anyone who doubts any of what I just posted take a case slid it as far into a sizing die as possible with your fingers and the see if you can tilt it even .001 degrees out of alignment when it is inserted into that sizing die. have fun because you can bend the case at the webbing you are not going to move it. Then slide the case into a shellholder and slide it in that die, uou can see the play between the case holder and the die but there is exactly 0 (zero) play between the sizing die and the case because the walls of the case conforms perfectly to the walls of the die. That is the purpose of having play in the shellholder and with some lockrings and presses play between the die and the press
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