squaring dies

[hounddawg]

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.

[F. Guffey]

Good post, dawg.

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.

Good post, dawg.

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

[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

[mikld]

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...

[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

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.

[hounddawg]

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

[mikld]

"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...

[F. Guffey]

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

[mikld]

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...

[gwpercle]

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

[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...

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

[cw308]

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 .

[hounddawg]

Worrying about press alignment its just another thing to drive yourself crazy . Reloading has enough twists and turns without adding another

not to mention it does not matter and even if it did the only thing you could do is rebore and sleeve it

[zeke]

https://sierrabulletsblog.com/2014/0...concentricity/

https://www.google.com/search?q=sier...hrome&ie=UTF-8

Just a slight rehash of what they used to have in their tips section.

[hounddawg]

I have two questions regarding statements in this article

Both the seating die AND the sizing die need to be squared to a dedicated shellholder in a dedicated 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

Or … you can invest in a Forster Co-Ax press and benchrest dies and kiss concentricity issues good bye.

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

[zeke]

hounddawg-So now you know better than Sierra?

As a demonstration. With the ram lowered, screw the die down past where it fully sizes the case without locking it down. Rock it back and forth and observe the play the coarse threads allow. Now let the die sit, again without locking it down. Raise the ram with a shell holder inserted till it makes contact with bottom of the die and pushes it slightly upward. Notice how the die straightens as pressure is slightly increased between the bottom of the die, and the top of the shell holder. If you lock the die while the pressure is present, you have now squared up the die. Again, just a demonstration, not how you set the die for the amount of sizing you want on the case. There are several differing ways to put pressure on the die to take up the slack of the threads.

Didn't figure this out, but first read about it in Handloader, decade or 2 ago?

Fortunately a high post count or tricky little by-line quotes does not an exspurt (PA redneck spelling) make.

[BumbleBug]

FWIW...the MEC Marksman press uses a floating shell holder to improve alignment. It's linkage does not allow a "cam-over" which took me some time to get use to.

[F. Guffey]

ZEKE, there was a big attempt to reinvent reloading, I never thought it would go as far as "be kind to your press". I wasted some time thinking there were a few reloaders that had shop skills, I did not assume they did not have a clue.

I said I have made tools for checking alignment of equipment, If what I attempted work I should be able to remove the alignment tool after applying pressure I should be able to assemble the equipment and then insert the alignment tool or I would be able to remove the alignment tool after applying pressure. Long before that I said the RCBS press is not a cam over press, I said it is a lock up press meaning it goes into a 'big time bind' when the ram is raised.

And what do I get back? reloaders claiming they are nicer to their press than I. And then there are the 'becauses'; because I use 'O' rings. And then there are those answers that come from reoaders that have never been under a press.

Reminds me of the train trip I thought I wanted to take; ever thing went OK until I found out what time the train arrived in New Mexico, Seems to me the train arrived in New Mexico before it left Texas. they asked me if I wanted a ticket, I answered no and then asked what it would cost me to watch the train take off.

[F. Guffey]

I said it is a lock up press meaning it goes into a 'big time bind' when the ram is raised.

I understand reloaders do not know what a 'big time bind' is because they have never been under a press.

F. Guffey

[hounddawg]

hounddawg-So now you know better than Sierra?

in this matter obviously anyone with two eyes and a bit of common sense does. A set of feeler gages is optional for the doubters

As a demonstration. With the ram lowered, screw the die down past where it fully sizes the case without locking it down. Rock it back and forth and observe the play the coarse threads allow.

which proves what? Is there more play when that die is screwed into a floating die holder on the Forster? As I keep pointing to there has to be play or float for a FL sizing die to work without damaging the case. Try rocking that die once the locknut is tightened down, you can't unless the press is a Forster and the die is sitting in a floating die holder

So #1 how do you adjust the die square to the case when everything that holds the case and the dies has .015" or more play in every direction

#2 how can that case enter the sizing die unless the walls of the case are perfectly aligned with the walls of the die without bending or gouging the case wall ?

#3 the author claims purchasing a Forster co ax will solve all problems with alignment , yet with that design not only the case has float in the shellholder but the die also sits in a floating die holder that slides in and out which would require several more thousandths freeplay

common sense isn't very common it seems

edit @ Bumblebug - all presses use floating shellholders to allow the cases to self align with the walls of the die as the enter. That has been my point since my first post

[GWS]

I'm not a machinist....just a building contractor.....I know nothing about how to machine anything to the amazing tolerances we all get to experience. So I have only respect for Guffy, Houndawg, and the rest, who can make sense of such. I've been reloading for nearly half a century, and I'm still learning.

The following are just observations gained from the past 48 years.

RCBS die instructions have always called for reloaders using their non-carbide dies to screw the die in to touch the shell holder with the ram raised fully in the press....then screw in another 1/8 to 1/4 turn for what they called "cam-over".

That insinuates that the ram goes to a "Top"...over it...then back down a tad. Guffy called it a "bump". Then he suggested a measurement....I assume being the distance it comes back down......if there is no back down....or bump....then it just got tighter....Guffy called it a bind....and I agree that it could bind things if you screw it down 1/2 turn or more.

So you might assume RCBS may have used the wrong term, "cam-over", when they what they really want is zero play from the course die threads and the linkage ...... why? So you can get a repeatable sizing....or in other words a repeatable distance from the case head to the shoulder ogee.

As Hounddawg suggests this is a vertical tolerance....and I agree than the ram ought to provide that without any "play" and/or "binding" that may throw things off horizontally.

As I learned from "Handloader" back in the '70's. You don't want to force a case into a die...misaligned. Back then they said, "be sure to loosen your shell holder snap-in spring so that there is movement available for alignment." I complied with that and case run-out improved. Lately I noticed some have replaced the snap-in spring with an "O" ring.....tried that....and it works, in spite of being an annoyment getting the shell holder in and out......I bagged that (set in my ways?) and went back to my loosey snap-in spring.

As for squaring dies with the shell holder......that's a no-brainer. Raise the ram so that it hits the die and raises it "square" against the die nut....then tighten the die nut set screw. The Lee "O" ring adds a slight horizontal alignment I doubt is needed as long as the shell holder is loosey. What it also adds is a little height loosey which can play hell with your finished vertical case measurements. Just my opinion

[hounddawg]

As I learned from "Handloader" back in the '70's. You don't want to force a case into a die...misaligned. Back then they said, "be sure to loosen your shell holder snap-in spring so that there is movement available for alignment.

and the same principles apply today, no movement = damaged cases

The Lee "O" ring adds a slight horizontal alignment I doubt is needed as long as the shell holder is loosey.

I think that statement pretty much sums it up and the Forster adds a little extra loosey by letting the die float as well

[GWS]

But what you don't want is vertical movement that is not always repeatable. the "o" ring on a Lee die supplies a little of that also.

Guffy in the past has talked about brass that wont size. I raised my eyebrows over that. Then I experienced that too. Old brass like some of the 1967 LC brass I still have......it's hard stuff and very springy. You can size it and you think it's where you want it and you measure it and find you have to size it again......best anneal it, then size it again.

I bought some recent MG LC brass a couple of years ago from Wideners. It was a lot newer yet it was over size so much that I had to size it at least twice sometimes more. Not only was it hard to size, it was hard to straighten. I found that resizing then rotating then resizing was the only way to get it there. The next reloading of it will require annealing first....should have done that after tumbling the first time. There is a thread here back a ways on that experience. I got some good knowledge from Uncle Nick and Bart B. in that thread.https://thefiringline.com/forums/sho...d.php?t=543610 If you're curious.

[hounddawg]

anyone with a Forster coax and a set of feeler gages that can tell us how much upward and horizontal play in the die holder? I never thought about it until now but the O ring on the Lee dies seem to be providing the same function by allowing the die a bit of float

[zeke]

"Mount your sizer (mine was an RCBS small based sizer) by tightening the die nut only after your die is height adjusted and the shell holder cammed over tight against the die."

GWS-Without getting into the cam over discussion, this "squares" your die to the shell holder. Can take this a step further by using the brass to square the hole in the die, instead of the case holder. While some may consider that excessive, have seen sizing dies where the sizing portion was not concentric with the die body or perfectly square to the die base.

hounddawg-Sorry, really can't explain it any simpler than what was done previously, and tired of repeating it over and over. Perhaps if you review the whole series of posts and can get to the point of distinguishing aligning from squaring, aka one plane 90 degrees to another. It might also help to realize a brass case can indeed be forced into a die that is not quite square, if you can recognize what a small degree it does it to.