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View Full Version : Head-to-head single stage press comparison, or "shootout"?



John Ross
02-21-2018, 05:27 AM
We all have our favorite single stage presses, and there are those that scour the Ebay listings for that coveted A2 or whatever, but has anyone ever done a head-to-head comparison of how the various presses compare using some kind of measurable numbers?

I have no training in mechanical engineering, so I'm throwing this idea out there in the hope that someone might come up with a testing protocol that would give us some useful data. Here are my thoughts so far:

Folks who make homemade rockets with hydraulic presses use Pressure-to-Force (PtoF) gauges to determine the loading pressure they are putting on their rocket comps in various size rockets. Purpose-built gauges made for rocket hobbyists cost around $125. Here is one example: https://www.woodysrocks.com/store/p86/Pressure_to_Force_Gauges.html

Alternatively, you can make your own for about $45 from this, by adding a dial indicator gauge: https://www.harborfreight.com/10-ton-hydraulic-short-body-ram-95979.html

Here is my (initial) idea:

1. Line up all the presses on a bench.

2. Fit them all with the same length handles, that have a way to hang a weight on the end.

3. Put the PtoF gauge in between the ram and the die, and have a bunch of solid metal spacers so that the ram can be made to hit the PtoF gauge at a number of specific handle angles throughout the length of its travel. Measure the angles with a Sears inclinometer: http://www.sears.com/craftsman-magnetic-universal-protractor/p-00939840000P?plpSellerId=Sears&prdNo=1&blockNo=1&blockType=G1

4. Hang a weight on the end of the handle, and take readings on the gauge at various specific handle angles for each press.

5. Measure ram stroke in inches and give % of total travel at each handle angle, because short-stroke presses have an inherent advantage.

At first blush it appears to me that this information would be useful to have. Does anyone have a better idea for a testing protocol?

"Heavy Hitter" presses to compare, including some high-end stuff (will edit to add suggestions):

RCBS A series, Rock Chucker, Big Max, .50 cal. (Ammomaster), Summit
Hollywood Senior
CH/4D Champion
Lee Classic Cast
Redding Ultramag
Hornady .50 cal
OWS Rock Crusher
Corbin S-Press
Corbin Mega-Mite
Walnut Hill

starmac
02-21-2018, 06:19 AM
Maybe we should test them all 100 times a day for, say 40 years to find out which ones wears out first too. lol

John Ross
02-21-2018, 06:29 AM
I have yet to encounter a loading press that was "worn out." Broken, yes, or rusted to the point of uselessness or with parts missing, but not "worn out."

Is your point that you think my idea of such a comparison test is meritless? If so, just say it.

lightman
02-21-2018, 06:52 AM
There was a recent thread similar to what you are talking about but I don'r remember the title. I think member jmorris devised a method to to some measuring. A search might turn up something.

I miss the old time stores that actually stocked reloading tools. I remember being able to look at different presses mounted on shelves.

Shawlerbrook
02-21-2018, 07:16 AM
I hope I live long enough to wear out a Rockchucker.

JBinMN
02-21-2018, 07:22 AM
Interesting.

Some folks might remember that "Consumer Reports used to be a magazine that reviewed different makes & models of all sorts of gadgets & mechanical stuff.


I thought about the OP & went and typed in the keywords "consumer reports reloading presses" in google & got 501,000 hits.

I did not limit this to "single stage" though. I will leave that to someone else if they wish to go look.
Like I said though, "Interesting".
:)

ioon44
02-21-2018, 08:37 AM
I hope I live long enough to wear out a Rockchucker.

Me too, I am wearing out faster than my Rockchucker.

richhodg66
02-21-2018, 08:45 AM
Seems all of them work OK. It boils down to personal preference. My main press is a Rockchucker, but I've used others and all it took was just getting used to them.

EDG
02-21-2018, 10:48 AM
Based on my 45 years using a Rockchucker none of us will reach that milestone.


I hope I live long enough to wear out a Rockchucker.

Walter Laich
02-21-2018, 11:16 AM
Seems all of them work OK. It boils down to personal preference. My main press is a Rockchucker, but I've used others and all it took was just getting used to them.

same here
example: when I inverted my press to size bullets the throw of the press reversed of course (actually it was still the same but now moving the handle up raised the ram) Only took a couple of sessions and it was ingrained in muscle memory

Plate plinker
02-21-2018, 11:56 AM
It’s seems that the results would be most useful for the swaging guys. Naturally the winning brand could use this type of info for marketing purposes.

LUBEDUDE
02-21-2018, 01:30 PM
There was a recent thread similar to what you are talking about but I don'r remember the title. I think member jmorris devised a method to to some measuring. A search might turn up something.
..........................

Yes, I remember Morris came up something, maybe a dial indicator?

country gent
02-21-2018, 02:23 PM
After roughly 15 years of high power rifle loading varmint loading and some handgun I needed to rebuild my coax. It was one with out the hardened shim under the shell holder and the block had bellied out. I set it up milled .060 off and put the hardened shim in. While I was at it I made new links and pins as they showed some wear also. I hardened the links and pins and since its easier when set up I made a spare set for it. This press loaded 5-8000 rds a year for those years.

It would be nice to come up with a way to measure force in to force out on various presses as a comparison, even better would be where in the stroke the top pressure is produced. At the bottom of the stroke little force is needed but at the force at the top of the stroke may make a difference depending on length of the cartridges being loaded and where it is highest. "IE" a hort pistol cartridge may onl need full force in the last 1" of the stroke, where a 300 win mag or 375H&H may need full force 2-3" down in the stroke. Heavy case forming may be even more important to this.

Char-Gar
02-21-2018, 02:26 PM
I have no idea why that test would provide useful information or why anybody would need it. There are many presses, new and used on the market with will take anything a reloader can throw at it and do for longer that the life of the reloader.

There are two kinds of presses, 1) good ones and 2) junk and most of us know which is which.

Ickisrulz
02-21-2018, 02:28 PM
It’s seems that the results would be most useful for the swaging guys. Naturally the winning brand could use this type of info for marketing purposes.

CH4d already claims it for their Champion press:

The Champion press body is a heavy duty 'O' type that cannot be sprung like other reloading tools. Our gigantic ram (largest in the industry) is 1.185" in diameter and has almost 16 square inches of bearing surface continually supporting alignment during the operational cycle. We worked over 2 years with several leading engineers from a major university to develop the new toggle system. Our computer designed toggle system is based on a proven compound leverage system and develops more force than any other hand operated reloading press - making the Heavyweight Champion the most mechanically efficient press in the world. This new toggle system allows you to swage the very heaviest bullets with ease !

http://www.ch4d.com/products/equipment/presses/033000

OS OK
02-21-2018, 02:42 PM
At the end of the day all you will determine is which one has the shortest cam and gives the most leverage with the least handle operating force.
In the end and outside of swaging that matters not...outside of it being the strongest leverage, it will prolly handle the shortest rifle round when seating without interference from the bottom side of the die itself.
Then there's the press frame strength without flexing, comparing a 'C' frame to an 'O' frame...
What does matter is whether or not it is easy to place a case in the shell holder without interference from some part of the press frame itself and how does this press handle spent primer debris...where does that go?
Another aspect I'd be concerned with is if I can see into the case without having to contort myself from the stool I operate it from.
Which press will accommodate a compact & efficient press light that wouldn't be just another appurtenance you have to work around?

Those are some of the differences I can think of that would matter most to me.

jmorris
02-21-2018, 09:40 PM
I made a little hydraulic load cell. To really tell you anything you need to be at the end of the stroke where all the work is done and leverage is highest.

This is what I rigged up first.
https://www.thehighroad.org/index.php?threads/how-much-force-does-my-press-exert.826834/

I used another force gauge to pull on the handle and found out I needed to change to a much higher gauge on my load cell. Then my o-rings leaked and I ordered quad seals. They came in right before I got real busy, need to get back to that project, can’t believe that was almost a year and a half ago.

Looking at my notes at .100” off TDC, 13.125 lb applied to the handle of the co-ax was 500 psi to the die. 16.75 lb in on a Lee Breech lock gave the same 500 psi at the same height from TDC.

Drew P
02-22-2018, 03:12 AM
One factor that’s important to felt exertion is ergonomics. The lee classic cast wins this with its adjustable position handle. This means you can put the hard part of the process in the strongest part of your particular arm. To me this is even more important than actual leverage. But I suspect you’ll find that the actual effort of the presses relates directly to the stroke length of the ram.

EDG
02-23-2018, 05:49 AM
There are several parts of reloading press design characteristics that can be analyzed with little actual testing.

1. Material properties

2. Force to stretch, deform or break the frame.

3. Ram force generated by a standard strength operator.

Materials:
This is the standard properties of the material from handbooks and suppliers literature.
Keep in mind that there is a property called fatigue limit or endurance limit. Significant cycles above this limit with eventually break the material. Below the limit there appears to be no limit to the number of cycles. That is the case with steel.
Cast iron has a lower fatigue limit so it will take lighter loads for large numbers of cycles.
Aluminum has no fatigue limit. No matter how light the stresses are, with enough cycles it is going to break. This is why aluminum is a poor choice for a press that will see long and high volume use.

Force to stretch the frame can easily be determined by modeling the frame with Finite Element Analysis. This is engineering software used to determine mechanical loads without a full scale test. This is how bridges, airplanes and buildings are designed.
Engineers used to do this with a slide rule and a pencil. You can still do this if you have the time to measure and sketch the press to be analyzed.

Force developed by a standard operator is just a standard input multiplied by the mechanical advantage of the press. This is the force developed in the last quarter inch or so of ram travel. Any engineer can do this with a pencil and a calculator.

If this number exceeds the strength of the frame the frame can be damaged.
If this does not exceed the frame strength the frame will be ok but the strength of the linkage may be the limiting factor.

I have a large number of SL54 US military 30-06 cases that were fired in a machine gun.
They caused the frame of my old Bair C press to temporarily spring open .007".
My 1971 RCBS Rockchucker sprung .002" using the same cases, the same die and the same lube.

I retracted the RCBS ram about 1/2" and sized the case a second time and the spring open disappeared giving more uniform sizing.

Green Frog
02-23-2018, 09:09 AM
While a measurement of force the press can exert is good, it would also be good to know how much force the press can withstand... a machinist friend of nine, now deceased, had me track down a Herter’s Super U for him after he broke a Rock Chucker doing some enthusiastic swaging. He was highly experienced if somewhat opinionated, but his opinions came from extensive experience. It finally dawned on me recently that if I want to settle on one single stage press, this should be the one. JMHO, YMMV, of course! :bigsmyl2:

Froggie

jmorris
02-23-2018, 10:14 AM
Force developed by a standard operator is just a standard input multiplied by the mechanical advantage of the press. This is the force developed in the last quarter inch or so of ram travel. Any engineer can do this with a pencil and a calculator.

It is also not linear. If it were linear it would be as simple as move the handle a known distance and record how far the ram moved and you will have a ratio. This is constantly changing though.

More difficult when almost none of the travel matters except the last few thousandths, where the work occurs. Lots of presses have “cam over” or the linkage goes over center at this point. That and manufacturing tolerances in the linkages even compound the difficulty/accuracy of any such measurements.

dragon813gt
02-23-2018, 11:52 AM
Specs mean nothing if you don't like using the press. It can have more leverage than you'll ever need but if one feature is missing, or it has one you don't like, then the press is useless to you. I don't like any press w/out a hollow ram for primer disposal. I don't like the ergonomics of the CoAx. So the specs are meaningless to me.

I bought an A2 to see what all the hype was about. It was hype all right. I will buy a dedicated swaging press for that function. And there are modern presses that are superior in all aspects except press material. There is no doubt cast steel is stronger. But it's not needed for reloading.

jmorris
02-23-2018, 12:11 PM
Yes, different strokes for different folks. The only press I have had with a hollow ram for primers was the Loadmaster but it wouldn't be my #1 pick.

EDG
02-23-2018, 08:57 PM
So?
For an easy solution you would be interested in the maximum force produced.
Any other solution is going to be comparing a set of curves. No operator has a calibrated arm that will care about the curve. Rather the maximum force generated is all that is likely to impress a human user.
Did you ever take integral calculus?
Well you can find the slope if a curve at any given exact point even though the line is not straight. The same thing can be done with these presses. Just find the mechanical advantage where it counts.
No one cares what the mechanical advantage is 2 inches from the bottom of the die.



It is also not linear. If it were linear it would be as simple as move the handle a known distance and record how far the ram moved and you will have a ratio. This is constantly changing though.

More difficult when almost none of the travel matters except the last few thousandths, where the work occurs. Lots of presses have “cam over” or the linkage goes over center at this point. That and manufacturing tolerances in the linkages even compound the difficulty/accuracy of any such measurements.

M-Tecs
02-23-2018, 09:00 PM
For some applications high force is great but for others it covers up the feel or sensitivity. The best is what fits into your needs and usage.

EDG
02-23-2018, 09:10 PM
Without numerical values you have no means of direct comparison of the mechanics.

There is no accounting for the touchy feely part of personal preference. But most people can tell the big number from the little number.

If I want a sensitive press I can use the dinky little Harrell's benchrest press.
Common everyday reloading is pretty much a high boredom low energy marathon. It is just a repetitive exercise that demands little from the press. I am more interested in how the press performs at very high loads while forming cases. Any old press can seat bullets and size pistol brass. If you are not interested in the maximum force data then you are free to pick a press based on any criteria you chose.

[88QUOTE=M-Tecs;4300154]For some applications high force is great but for others it covers up the feel or sensitivity. The best is what fits into needs and usage.[/QUOTE]

jmorris
02-23-2018, 09:50 PM
So?
For an easy solution you would be interested in the maximum force produced.

Ok, calculate it for the presses you have an post it, if it’s as easy as an engineer and a pencil.

How much do the presses mechanical advantage change over that last .25”, that you have?

FWIW they don’t make force only multiply what force is input to them.

Jtarm
03-01-2018, 06:12 PM
Me too, I am wearing out faster than my Rockchucker.

Same here.

Snow ninja
03-01-2018, 08:53 PM
Might want to add Forester Co-Ax to the list.

maxreloader
03-01-2018, 09:35 PM
Dare I use the word "sexy" to describe a press? In the spirit of the OP and in the pursuit of ergonomics I can tell you that after using many, many brands, styles, types of presses that the star universal is the smoothest and the hollywood senior is the easiest on the body. I have literally had to bear-hug a RCBS ammomaster set up for 50 bmg to size LC brass... what a ca-ca setup. It all boils down to what you actually need and how you want to feel doing that job. I know guys that can afford pretty much any vehicle they could want and drive vintage vehicles because they like them. I use what works best and feels best for the job at hand with the means available to acquire. John asked a question and none of us except maybe jmorris has actually posted any answers that is what he may be looking for. :drinks:

lightload
03-03-2018, 11:18 PM
I have so many presses that I occasionally give one or two away to a young person, and then I'll fret and buy more. Many(most?)hand gunners could get by nicely using a Lyman Spartan or Spar-T, yet we all have heard that they are both obsolete. The press I'm most proud of is the new with the hanging tags Spar-T that I was given not long ago. I'm awaiting an Ultramag from bullets.com but have no great need for its leverage capability.

Rick Hodges
03-04-2018, 09:18 AM
It seems to me that putting the same handle on all the presses defeats the purpose. The handle is an integral part of the press, the "user interface" and a large part of what makes a press comfortable to use.

Lloyd Smale
03-04-2018, 10:19 AM
I own or have owned a rock crusher, co-ax, orange crusher, rcbs Jr. and a hornday lnl. None of them does a single thing the others wouldn't do just as well.