Don't stress your press
- Thread starter hounddawg
- Start date
@CW- yep. I set the barrels for GO gage headspace, add a brass .003 shim to the GO gage at the bolt end and make that my NOGO length. Then set the sizing die to GO gage length. Gives me .002 - .003 clearance on my sized rounds and I can swap the same cartridge between guns when I have them barreled for the same cartridge.
consistency, that is what it is all about. Like you I have no idea why anyone would need to cam over to size a standard case. I just FL sized 75 .260 cases this morning, all are perfectly sized and not once did I cam over the press
consistency, that is what it is all about. Like you I have no idea why anyone would need to cam over to size a standard case. I just FL sized 75 .260 cases this morning, all are perfectly sized and not once did I cam over the press
Not true! In the early 30s a company described the function of their tool, they described the function as 'leaver lock'.
A reloader with minimum shop skills should have the ability to measure the amount of cam over in thousandths. I have had 5 Rock Chuckers, I modified one to cam over; the other 4 are not cam over presses.
One more time: I have two Rock Chuckers with Piggy Back 11 attachments; the Piggy Back 11 attachments is designed to auto advance meaning the ram can not reverse directions. Starting over for reloaders that are shop skill challenged; The ram on a cam over press goes up and stops and then changes directions (that change in directions is the origin of the word 'bump')
The ram bumps on the way up and again on the way down if the reloader understands the ram must travel up before being lowered (on a cam over press).
Back to the auto advance, if the ram changes directions the one way clutch in the Piggy Back 11 attachments prevents it (from reversing directions).
F. Guffey
Guffey
Why would you spend time modifying a RockChucker press to cam over. I don't have your background in machinery , maybe you just like to tinker , I could see that . But in accurate reloading I can't see any good in stressing something . My way of thinking a brass case against a steel rod 1" thick is no challenge so why not do it with the right equipment. I size like hounddawg never had to cam over and I'm turning out accurate reloads . I'm not into chronograph SD/ ES or XYZ my group let's me know what works . With the me factor added in with my reloading and shooting , would neck turning make my groups any tighter . I think it may just come down to , some just like to tinker . I like to keep it simple but accurate .
Why would you spend time modifying a RockChucker press to cam over. I don't have your background in machinery , maybe you just like to tinker , I could see that . But in accurate reloading I can't see any good in stressing something . My way of thinking a brass case against a steel rod 1" thick is no challenge so why not do it with the right equipment. I size like hounddawg never had to cam over and I'm turning out accurate reloads . I'm not into chronograph SD/ ES or XYZ my group let's me know what works . With the me factor added in with my reloading and shooting , would neck turning make my groups any tighter . I think it may just come down to , some just like to tinker . I like to keep it simple but accurate .
I'm trying to follow this discussion and a lot of it is over my pay grade, being a chemist rather than a machinist or engineer, but let me ask what might be a simplistic question.
Isn't it the object of RCBS instructions to cam over the case to ensure the resulting full-length resized case will fit all rifles in that caliber? If I want to set the shoulder back .002" I follow the RCBS instructions, then back the die out, re-measuring the shoulder setback until I reach my goal. At that setting the cases may not chamber in another rifle of the same caliber. Or I am I not even in the same ballpark in this discussion?
As well, the press is attached to the wooden bench. Isn't it likely that the bench attachment will give in to the force of over camming before the press linkage does?
Isn't it the object of RCBS instructions to cam over the case to ensure the resulting full-length resized case will fit all rifles in that caliber? If I want to set the shoulder back .002" I follow the RCBS instructions, then back the die out, re-measuring the shoulder setback until I reach my goal. At that setting the cases may not chamber in another rifle of the same caliber. Or I am I not even in the same ballpark in this discussion?
As well, the press is attached to the wooden bench. Isn't it likely that the bench attachment will give in to the force of over camming before the press linkage does?
I am convinced adjusting the die to the press is beyond most reloaders ability to understand.
Again, my favorite cases are cases that are too long from the shoulder to the case head meaning the case is too long from the shoulder to the case head to allow the bolt to close. Manufacturers of components do not sell cases to reloaders that know and understand what they are doing so they sell cases that are considered minimum length or cases that are full length sized.
Many times I have asked where did the 'magic .002"' come from.
When a reoader adjust the die to size the case to minimum length or full length sizes the case the die is adjusted down to the shell holder on a non cam over press; after contact the die is lowered .017" or as we say 'lowered/turned 1/4 turn. If the press is a cam over press the amount of cam over must be added to the 1/4 turn. That would be .017" plus cam over. No one measures cam, if they did and they were using a Rock Chucker they would know the Rock Chucker does not cam over. The Rock Chucker goes into a bind when the linkage makes contact. The ram is kicked forward at the top and back at the bottom so if I had to describe the Rock Chucker I would say it is a 'BINDER'; when the linkage bottoms out it goes into a bind.
And then there is the infatuation with the head space gage. If the reloader could verify the head space gage they could determine the head space gage is .005" longer than the minimum length/full length sized case. To verify the die simply remove the primer punch/neck sizer assemble and then drip the head space gage into the die. For the 30/06 die the head space gage should protrude .005" from the die.
But there are layers and stacked stuff that must be considered. If the die is adjusted to restore the case to minimum length/full length sized the die must make it down to the top of the shell holder, that is the part that is impossible to keep up with. That is when the case has more resistance to sizing than the press, die and shell holder can overcome.
When sizing the case for minimum length or full length sizing the die must be lowered when the case has more resistance to sizing than the press can overcome; so? It becomes necessary to add an additional 1/4 turn to the 1/4 turn the reloader starts with.
A reminder: My favorite shell holder is the RCBS shell holder because it fits like a hand me down shirt; it fits only where it touches. And again I can reduce the length of a case from the shoulder to the case head .010" by adding a .010" shim between the deck of the shell holder to the bottom of the case.
So if I need a special shell holder I know how special it has to be. I know; there is Redding special shell holders, problem, the Redding only increases the distance from the deck of the shell holder.F. Guffey
Going back a decade here in this forum:
We have this
Just in this forum there is likely a dozen threads on the subject over about as many years and each thread always ends up looking just like this thread. Just in the very beginning of this thread there were links to two conflicting articles by two pretty well known writers on the subject. A simple Google of the subject matter will yield God knows how many discussions on the subject and for the most part they look very much like this thread.
Just do whatever works for you as I really doubt there is a correct or incorrect way to resize a case short of destroying the thing or doing irreparable damage to your press. While I have several presses and like many a pile of assorted gauges I tend to gravitate to single stage and while I like my old Lee "O" press which is an aluminum frame I like my Rockchucker likely the best since I don't have a Co-Ax which I am sure I would love. I also as to gauges like my RCBS Precision Mics a little more than my Hornady Lock and Load gauges. All of which is just a matter of personal like.
The end of this is always going to be what works best for an individual and the individual knowing best how to use the tools, be it a press or gauge which works best for them.
Next year, when the subject surfaces again we can all enjoy a rerun of what seems to be an unending saga.
Ron
We have this
Just in this forum there is likely a dozen threads on the subject over about as many years and each thread always ends up looking just like this thread. Just in the very beginning of this thread there were links to two conflicting articles by two pretty well known writers on the subject. A simple Google of the subject matter will yield God knows how many discussions on the subject and for the most part they look very much like this thread.
Just do whatever works for you as I really doubt there is a correct or incorrect way to resize a case short of destroying the thing or doing irreparable damage to your press. While I have several presses and like many a pile of assorted gauges I tend to gravitate to single stage and while I like my old Lee "O" press which is an aluminum frame I like my Rockchucker likely the best since I don't have a Co-Ax which I am sure I would love. I also as to gauges like my RCBS Precision Mics a little more than my Hornady Lock and Load gauges. All of which is just a matter of personal like.
The end of this is always going to be what works best for an individual and the individual knowing best how to use the tools, be it a press or gauge which works best for them.
Next year, when the subject surfaces again we can all enjoy a rerun of what seems to be an unending saga.
Ron
Thank you BBarn; I feel like the Indian of many years ago, it was close to 1816 when the Indians had to make a meeting they were not prepared for so they went to Canada and returned with an Indian no one liked. to make it understood and clear to all the Indians reminded him his own people put him on trial and found him guilty.
His confidence builder came in his response; he acknowledge he lost but he made it very clean when he started all of the Indians were against him and when finished one of them had doubts about his guilt so? He took exile in Canada. It was not easy being him; the Indians did not like him and the white guys hated him.
F. Guffey
If I tell you a chicken dips snuff please do not argue; first! Catch that pullet and check under its wings to determine where she carries her can. The problem with many reloaders is about time they have invested in something that did not happen does not happen. And then there is credit, we all know about the shooter that took himself too serious and claimed the case has head space. At the time I do not believe he was familiar with SAAMI.
He argued and then called SAAMI, again I am sure they were impressed with his shooting but SAAMI is the one that does not list case head space in their case drawings. I do not have trouble with accepting SAAMI because without SAAMI we have reloaders that take themselves too seriously and then start making this stuff up.
And then there was a member that reported me to RCBS; the tech. person gave the complainer a phone number and an extension with his name. All I have tried to do is get reloaders to push themselves away from the keyboard.
I have a Rock Chucker attached to a stand, I also have one that is in a cabinet, I also have one that is attached to a Piggy Back 11 attachment, The attachment has a one way clutch; I also have a spare one way clutch.
F. Guffey
I size my cases to what works best in my chamber , I know my chamber length and I size accordingly.On long cases as F. Guffey posted I wouldn't size back to spec but to .001 - .003 depending on what it's used for . No need for cam over but to me that chamber was cut too long . Long or short chambers what is the point in cam over . Sorry to beat a dead dog to death but I see no good in cam over . Guff I'm getting like you making a short story long . Always good talking gun stuff though no matter how old the subject is .
Chris
Chris
I think the issue here is people stuck on the cam over thought and not what it signifies . All cam over is asking the reloader to do is make hard contact between the shell holder and die . If I adjust the die as RCBS and Redding for that matter instruct in my Lee classic turret press . I will not have cam over because it's impossible to cam over a Lee CTP . I will however get hard contact between die and shell holder resulting in the same sized case as if I sized it in a press with cam over .
Yes the instruction that are written that way are to ensure a case sized this way will chamber in any factory SAAMI spec chamber . It is not to ensure best fit for "your" chamber .
Here is why I ran those tests 5 years ago I explained earlier .
These case head separations were only after my third reload of these cases
This was do to adjusting the die as instructed by Redding and using a standard shell holder . I don't remember the actual number but I had something like .008+ of head clearance . Meaning ( ball park numbers not actual measurements ) my sized case measured 1.624 and my fired case measured 1.632 . That was allowing the web to stretch .008 each time the case was fired . After .024 of stretch the cases failed .
It was then I started disregarding the instructions , which is not always that easy to do when reloading . Disregarding some instructions can get you killed so I was a bit hesitant at first not knowing at the time if die adjustment instructions was one of them that could get you hurt .
That was also around the same time I started to understand sizing the cases minimally. When I was trying to only bump my shoulders .002 some would bump more while others would not bump at all. At the time I was not measuring my head to datum distance . I did the old size a fired case minimally then try to chamber . If I felt resistance I screwed the die down a tad more , sized and chambered again . Repeat until the bolt closed feely then lock the ring down . However I found later some cases would chamber with ease while others would have some resistance still when closing the bolt after sizing a few hundred cases at that die setting . It was then I learned my Hornady press linkage deflects a lot and was the primary cause of those inconsistencies as described above and in my post with the press deflection pics .
The only way I was able to stop the inconsistencies while backing the die off a standard shell holder deck hight when using my Hornady press was to start using Redding competition shell holders . They allow me to size my cases that .008 longer while at the same time forcing all that deflection issues out of my press .
I'm sure other presses don't have as much flex as my Hornady does and might be why some of you don't seem to have the same issue or don't notice it . I however do have an issue with press deflection be it in the frame or linkage makes no difference to me . Although it's my belief it's more in my linkage then anything else .
All that said , my Hornady press is designed to cam over or at least it's able to do so . I can set the die down lower to not allow for cam over and if I use the comp shell holders my cases come out the same as if I cammed over as long as the die and shell holder makes hard contact with each other .
As to press deflection likely only being in the linkage . I'll go with maybe most of it is in the linkage but there are many presses out there that the press frame and or other parts that are not the arm linkage that allows for or do simply flex . The little cheap Lee press will flex but the type that will flex the most and maybe flex is the wrong word is C type turret presses . Namely the Redding T7 press flexes for sure do to the open face design , tolerances in the tool head and the long cantilever design of the 7 station press head .
I know the T7 has this issue because I helped a guy out that was having the same issue with his T7 I was having with my Hornady single stage . He would get very consistently sized cases from head to datum point if his dies and standard shell holder made hard contact . However that setting sized his cases .006 more then what he wanted which was a .002 bump . When he backed the die off the shell holder to size the cases correctly . The cases started being sized very inconsistently . To get every case to bump at least .002 some were bumped .004+ do to the press flexing . I recommended he try the competition shell holders and it resolved his problem .
I'll add that I don't "need" the comp shell holders to size my cases . I use them to get a more consistent sized case from case to case . I'll add I load for multiple 308 rifle with all having slightly different headspace dimensions and never need to adjust my die to get my .002 bump regardless of the rifle I'm loading for or cases I'm sizing or times fired . If it's the longer chambered rifle I use the .008 comp shell holder and if it's the smaller chambered rifle I use the .004 shell holder never needing to adjust the die it self and still get the perfect .002 bump . I have not adjusted my lock ring on my 308 or 223 sizing dies in years just insert the correct shell holder for the rifle and or cases being sized and I'm gtg .
If anyone's wondering how could write such a lengthy post when football is on . Let's just say I stopped watching my charges somewhere in the first half
Yes the instruction that are written that way are to ensure a case sized this way will chamber in any factory SAAMI spec chamber . It is not to ensure best fit for "your" chamber .
Here is why I ran those tests 5 years ago I explained earlier .
These case head separations were only after my third reload of these cases
This was do to adjusting the die as instructed by Redding and using a standard shell holder . I don't remember the actual number but I had something like .008+ of head clearance . Meaning ( ball park numbers not actual measurements ) my sized case measured 1.624 and my fired case measured 1.632 . That was allowing the web to stretch .008 each time the case was fired . After .024 of stretch the cases failed .
It was then I started disregarding the instructions , which is not always that easy to do when reloading . Disregarding some instructions can get you killed so I was a bit hesitant at first not knowing at the time if die adjustment instructions was one of them that could get you hurt .
That was also around the same time I started to understand sizing the cases minimally. When I was trying to only bump my shoulders .002 some would bump more while others would not bump at all. At the time I was not measuring my head to datum distance . I did the old size a fired case minimally then try to chamber . If I felt resistance I screwed the die down a tad more , sized and chambered again . Repeat until the bolt closed feely then lock the ring down . However I found later some cases would chamber with ease while others would have some resistance still when closing the bolt after sizing a few hundred cases at that die setting . It was then I learned my Hornady press linkage deflects a lot and was the primary cause of those inconsistencies as described above and in my post with the press deflection pics .
The only way I was able to stop the inconsistencies while backing the die off a standard shell holder deck hight when using my Hornady press was to start using Redding competition shell holders . They allow me to size my cases that .008 longer while at the same time forcing all that deflection issues out of my press .
I'm sure other presses don't have as much flex as my Hornady does and might be why some of you don't seem to have the same issue or don't notice it . I however do have an issue with press deflection be it in the frame or linkage makes no difference to me . Although it's my belief it's more in my linkage then anything else .
All that said , my Hornady press is designed to cam over or at least it's able to do so . I can set the die down lower to not allow for cam over and if I use the comp shell holders my cases come out the same as if I cammed over as long as the die and shell holder makes hard contact with each other .
As to press deflection likely only being in the linkage . I'll go with maybe most of it is in the linkage but there are many presses out there that the press frame and or other parts that are not the arm linkage that allows for or do simply flex . The little cheap Lee press will flex but the type that will flex the most and maybe flex is the wrong word is C type turret presses . Namely the Redding T7 press flexes for sure do to the open face design , tolerances in the tool head and the long cantilever design of the 7 station press head .
I know the T7 has this issue because I helped a guy out that was having the same issue with his T7 I was having with my Hornady single stage . He would get very consistently sized cases from head to datum point if his dies and standard shell holder made hard contact . However that setting sized his cases .006 more then what he wanted which was a .002 bump . When he backed the die off the shell holder to size the cases correctly . The cases started being sized very inconsistently . To get every case to bump at least .002 some were bumped .004+ do to the press flexing . I recommended he try the competition shell holders and it resolved his problem .
I'll add that I don't "need" the comp shell holders to size my cases . I use them to get a more consistent sized case from case to case . I'll add I load for multiple 308 rifle with all having slightly different headspace dimensions and never need to adjust my die to get my .002 bump regardless of the rifle I'm loading for or cases I'm sizing or times fired . If it's the longer chambered rifle I use the .008 comp shell holder and if it's the smaller chambered rifle I use the .004 shell holder never needing to adjust the die it self and still get the perfect .002 bump . I have not adjusted my lock ring on my 308 or 223 sizing dies in years just insert the correct shell holder for the rifle and or cases being sized and I'm gtg .
If anyone's wondering how could write such a lengthy post when football is on . Let's just say I stopped watching my charges somewhere in the first half
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I ask: Again and again and again etc. where does (did) the magic .002" come from. I believe your arms are going to be worn out petting your friends and your self on the back before you ware out your arms sizing cases on your presses.
If you are going to eliminate the die from contacting the shell holder you will sacrifice leverage. When you adjust your die to size the case you are controlling the length of the case from the shoulder to the case head.
One more time and again and again and again I have one rifle that has a chamber that is field -gage length plus .002". WHAT DOES THAT MEAN? ! It means the clearance in the chamber when firing minimum length/full length sized case or over the counter ammo or factory loaded ammo the clearance is .016".
And then? WHAT TO DO? I size 280 Remington cases to 30/06 with a gap between the bottom of the die to the shell holder .014". The 280 Remington case is .051" longer from the shoulder of the case to the case head than the 30/06 case from the shoulder to the case head.
And now? I do not believe you understand what happened when the press reduced the length of the case .014"
I backed the die off .014" if the press was a non cam over press, if the press was a cam over press I could subtract the amount of cam over from the .014".
Again I had a friend that adjusted his A2 cam over press with 1/2 additional turn after contact with the shell holder meaning he lowered the die .044". his press by design had a cam over of .017". When lowering the ram he had to raise the top of the press .051".
F. Guffey
All this got me thinking I know ! Have presses always been able to cam over ? I know some don’t and may never been built to do so but since there has been presses for reloading has there always been a type that cammed over ?
My thinking is maybe the die instruction have been around much longer then the cam over press ??? May be why following the die directions when using a pess that cams over puts to much stress on that type of press ??
I know ! Have presses always been able to cam over ? I know some don’t and may never been built to do so but since there has been presses for reloading has there always been a type that cammed over ? My thinking is maybe the die instruction have been around much longer then the cam over press ??? May be why following the die directions when using a pess that cams over puts to much stress on that type of press ??
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I raised the ram on one of the most abused Rock Chucker press in existence today. When the ram hit bottom the handle continued moving and then suddenly and without warning
the ram hit the floor. Conveniently my wife was near by so I could use her as an excuse if RCBS argued.I called RCBS, they said they would send me another one and I got concerned and ask them; "ANOTHER WHAT?" because I was not going to accept a new press. I wanted the (my) same press.
Immediately they said they would sent me another ram with a repair kit, and that is what they did. I did not care if the ram was new and or used. Again, this press was used with other presses like Herter presses etc.
I did replace the handle on one of my Herter presses, my wife hit the handle with her 4 door 68 Bonneville with the 455 cubic inch engine. I tried to lecture her but it was not her that left the handle down.
F. Guffey
So you do not know the distance from the shoulder in the die to the deck of the shell holder? And you do not know if the case won or the press won? And you do not know how to increase the presses ability to overcome the case's ability to resist sizing? and then there is that gap between the bottom of the die and top of the shell holder?
F. Guffey
Here's more to confuse or help clarify depending on what side of the fence you sit
https://precisionshooter.info/cam-over-on-a-reloading-press/
https://precisionshooter.info/cam-over-on-a-reloading-press/