Don't stress your press

Posts: 2,136
Been working on machinery for over half a decade and yes anything can fail. They will break for no reason at all but they will break more often if they are regularly over stressed or abused.
Being made in China seems to give machinery all the reason it needs to fail.
I had to replace 12 bearings this week. Went to the parts house to order Dodge bearings. Guy told me, "You don't want Dodge, they cost $625 each and the Chinese bearing is only $300 each." I told him "order the Dodge bearings." Money WELL spent.
 
Last edited:
Metalgod: Well done on the link

The evil head space comes up again.

I don't have a problem with a quick set and measuring and tune it to what I want.

I use the Lee O rings and can tweak it back and forth.
 
Being made in China seems to give machinery all the reason it needs to fail.
I had to replace 12 bearings this week. Went to the parts house to order Dodge bearings. Guy told me, "You don't want Dodge, they cost $625 each and the Chinese bearing is only $300 each." I told him "order the Dodge bearings." Money WELL spent.

That may be part of it but when I was 15 I started sweeping up in my uncles machine shop which was rural enough which mostly made parts for sawmills, farm equipment and anything else that someone needed yesterday. Stuff broke then, it breaks now. I made a nice living fixing it and still love to tinker.

I still don't see what is so complicated about setting a die. I just set up my new 6.0 CM sizing die in about 15 min using a freshly fired case and a Hornady comparitor. Resized cases are coming out exactly .003 under where they went into the die.

I started with the die touching the shell holder, backed it out 1/2 turn, lubed a case, sized it, measured it, turned the die in about 1/16th and repeated until the case measured .003 under what it went in. Locked the ring and that was that. No PHd required, no cam over required so why over complicate ?

I did check the sized case against my GO gage and they are the same so I think I'll call the adjustment a success
 
I don't know if this has been mentioned before, but a quarter turn of a die moves the base up or down just a bit over .02. Mine doesn't have a loose connection, it has a stop point. I set my shell holder to touch the die and crank it in another 1/8, and that essentially makes the thing hit the die and firmly press. That won't be able to cause any particular problem, there are at least a dozen places on the mechanism that will be able to absorb the bit of extra pressure. all of the toggles, all of the gaps, etc, a little stretch here, a little squish there, that isn't going to damage a quality steel mechanism.

There is a valid question of what sort of equipment is being used. A sloppy piece of poorly machined aluminum or a tightly constructed iron one? A small unit for standard centerfire, or something built for swaging shells and reloading 50 bmg?


Do people set their presses so that they have an entire round of the die threads turned in after TDC? If a person is running much more than 1/8 or 1/4 extra depth there's more pressure than should be applied to machinery. It depends on the robustness of the press and how long the ram travel actually is.

I noticed that my son in law wasn't aware of the power generated by a press. So, I put a 9 mm casing in a shell holder and dropped the ram with a bit of plywood under the die. Well, you guys know that it punched out a plug just by letting the ram drop. The leverage exerted by the big presses is uncanny.
 
briandg, I have said I have turned cases into accordions or a case with bellows.

All of that in an effort to explain how difficult it is to bump/move the shoulder of the case back with a die that does not have case body support; the problem? Too much information for most reloaders to keep up with.

I have presses that use dies with 14 threads per inch meaning each turn of the die raises/lowers the die .071429+". 1/4 turn of the die raises/lowers the die .01785".

I do have presses that do not use 14 threads per inch. To use those dies in other presses I use an adapter if I ever decide to use the small dies in bigger presses.

In the perfect world raising the ram with an additional 1/4 turn (down) after contact the case will be returned to minimum length/full length sized. (still in the perfect world because the chamber is go-gage length). this method/technique results in the case having clearance. The clearance is the difference in length between the chamber from the shoulder to the bolt face and the case from the shoulder to of the case to the case head.

the difference in length between case length and go gage length chamber is .005" for the 30/06. UNLESS the reloader chooses to stack tolerances, variables, SAAMI spreads; or if the reloader is using the 'could be' philosophy as in "it could be this and or it could be that".

I am the fan of reducing all that case travel. I start by measuring the length of the chamber from the shoulder to the bolt face; others choose to start by firing first and then measuring. If I fire first I must measure first; I want to know what effect the length of the chamber had on the case when fired. Again: Case manufacturers do not manufacture cases for reloaders that know what they are doing. Meaning? I am the fan of starting with cases that will not allow the bolt to close, I start by determining the length of the chamber from the shoulder of the chamber to the the bolt face.

F. Guffey
 
Last edited:
I still don't see what is so complicated about setting a die.
Because, this is the internet. Nothing is simple. I set my body die up for my 6 PPC in about 2 minutes. Took less time than that for the neck die. I am confident that rifle with those loads is more accurate than 99.9% of what we are "discussing" here.
 
I still don't see what is so complicated about setting a die.

Nothing is really but this thread is not about setting up your die specifically . It's about setting up the die in your press in such a way it overly stresses the press to possible failure .

What the issue is IMHO is guys not staying true to the context of the thread . I said it before that this discussion seems just like the cleaning your firearm threads you see . " Cleaning your firearm can damage it ! " NO it can't "if" done correctly" Sure if you want to take things out of context then yeah cleaning your guns damages them . It seems at times when responding to something we can stray from what's actually being asked or stated .

So yeah all things break and all things need fixing , but lets dive a little deeper now . How many thousands of Rockchucker single stage presses have been sold ? How many of those are still out there working just as well as they did when new ? Seeing how the internet points out how bad everything is . How many Rockchucker presses have we all read about breaking in half ??? Now how many have we heard about as being one of the best presses and most sturdy . Also likely the most recommended single stage press to buy .

You don't get that reputation if simple cam over is snapping your presses in half . We would be hearing by now how presses that never cam over last longer then those that do . There is enough people out there using these presses as well as enough trolls out there that "if" cam over was really hurting presses there would be clear evidence of it .

Yet we still seem to except posters taking things out of context in there reply's . Of course if you OVERLY stress or ABUSE something regardless of how it's made it has a greater chance of failing . Again are we taking these things out of context . Does camming over put more stress/load on the press then if the shell holder and die barely touch with no cam over ? Almost certainly but does camming over as instructed OVERY stress the press to likely failure or reduce the life of the press ? Almost certainly not or we'd already know it . Reloading presses are not something new that we just don't have enough info on .
 
Because, this is the internet. Nothing is simple. I set my body die up for my 6 PPC in about 2 minutes. Took less time than that for the neck die. I am confident that rifle with those loads is more accurate than 99.9% of what we are "discussing" here.

quite sure you are right on all counts. I could have probably went faster but I snuck up on the final depth and then double checked it against my GO gage and a new case.
 
if someone would post a link to something repeatable that showed how camming over helps in any way I might consider doing it. So far all I have seen is certain die manufactures recommend it. I don't use that brand anyway. Just double checked the instructions on my Redding FL dies and nowhere does it state to cam over the press. In fact it says to adjust the way I just described in my post above.

@Metalgod , as I interpret it the phrase "OVERLY stress or ABUSE something " means that I should only apply as much stress as needed. So if my cases come out to my desired measurement by simply stopping when the case tops out why should I continue to add additional stress. To me that is the very definition of "OVERLY stress or ABUSE
 
Sorry man , I wish I did post videos because I could easily show you how my press is very inconsistent unless I cam over . Firearm forums is my extent of social media . I have no facebook , twitter , youtube or other accounts .

I can run those same test again which is sizing several different manufacturers cases with different number of firings .All while having the same die settings , one with cam over and hard contact with the die and shell holder and the other with a slight gap between the die and shell holder . Then post the results in writing if you'd like but you just have to take my word on it .

@Metalgod , as I interpret it the phrase "OVERLY stress or ABUSE something " means that I should only apply as much stress as needed. So if my cases come out to my desired measurement by simply stopping when the case tops out why should I continue to add additional stress. To me that is the very definition of "OVERLY stress or ABUSE

My interpretation is slightly different but I don't disagree with yours in general . Mine is more stress then the press was regularly designed to withstand . We are talking about overly stressing the press and not exerting more force then necessary to size your case correct , or at least that's what I thought we were originally talking about . You don't need cam over to get perfectly sized cases but I do and IMO neither of us overly stress are presses . I likely put a heavier load on mine then you do but not so much that my press is likely to fail before yours is all my point has been .

We can take it one step further and talk about sizing very large cases in comparison to smaller ones . Meaning sizing a 300WM with out cam over will likely stress my press more then lightly camming over when sizing a 223 case .
Meaning presses in general are designed to handle a pretty heavy load when you think about all the large cartridges you can size on a standard sized press .
 
Last edited:
Question. Does the Redding Big Boss 2 cam over? I am thinking about replacing my oldest press and the bb2 looks good, just can't find any info about camover. Hopefully it does not.
 
Last edited:
Take a very close look at the linkage at the bottom of the press and you will see a black pin that protrudes out to the linkage, and this stops the press at top center. It doesn't cam over, it has a positive stop if you choose to use it.

This photo from Midway USA shows it very clearly.

271710.webp


https://www.midwayusa.com/product/1013047556/redding-big-boss-ii-single-stage-reloading-press
 
You will like your press. The components are precise. Linkage is strong, and precise. The priming setup is odd and you may choose not to use it, using a hand primer or other device, I personally don't use it. You will get excellent power at the end of the stroke. The discarded primer trapper in the earlier presses isn't particularly well designed, and the original design wound up with primers all over my room. I've owned and used a boss for years and I have no significant problems with it.
 
I was getting sized brass with the shoulder set back to 1.624 and took feeler gages and tried to slip them between the top of the caseholder. I came up with about .009 clearance.

What does that mean?

And then you lowered the die 1/2 turn:eek: (.034"):rolleyes: As a results of the additional 1/2 turn you reduced the length of the case from the shoulder to the case head .009".

You increased the presses ability to overcome the cases ability to resist sizing. In the beginning I measured the length of the case from the shoulder/datum to the case when determining if the case won or the press won.

WHAT DOES THAT MEAN?

I adjusted the die to overcome the cases ability to resist sizing first. If the
the die does not make it to the shell holder the case has more resistance to sizing than the press can over come.

F. Guffey
 
What does that mean?

I will never understand why reloaders insist on starting over everyday.
The deck height of the shell holder is .125". The distance from the shoulder in the die is to the deck of the shell holder for the 30/06 (die) is .005" shorter than the length of a go-gage from the shoulder/datum to the head of the gage.

Meaning: When the die is adjusted to size the case to minimum length/full length size the case there will not be a gap between the bottom of the die and top of the shell holder.

AND!: If a 30/06 head space gage is installed into he die with the shell holder the gap between the bottom f the die and top of the shell holder will be .005".

If a reloader could manage to remove the die from the ram without removing the case after sizing the protrusion of the case head from the die would be .005 if the die made it to the shell holder when the ram was raised.

I know; it is much easier to type "I bumped the shoulder back".

F. Guffey
 
I'm back guys and I see nothing has changed ,. All the back and forth with sizing . I still feel its only removing the slop in the press , you can't make the ram and die bottomed measurement any smaller . Removing the slack in all the linkages after the die is set , if you call that cam over I would agree .

Chris
 
Removing the slack in all the linkages after the die is set , if you call that cam over I would agree .

First; to understand cam over the reloader must understand cam over. When I bolt my Herter 2 ram press to a stand I know both rams cam over. When I bolt my Herter turret to the sand I know the ram bumps the bottom of the die twice, once on the way up and again on the way down because I know the Herter turret press is a cam over press and I understand it is also called a bump press.

Bump? I understand how impossible it is to bump the shoulder back on a case with a die that has case body support; I am guessing bump has appeal because it is a cute/catchy word.

F. Guffey
 
And I have a strain gage, this gage is not the gage reloaders confuse with tension as in being a tension gage and it is consistent with my other tension gages; it measure in pounds, lots of pounds.

F. Guffey
 
Back
Top