Any ideas on the pressure generated by different presses? Corbins´, DIY press (the one on the forum), Rock Chucker, Lee Classic cast....?
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Any ideas on the pressure generated by different presses? Corbins´, DIY press (the one on the forum), Rock Chucker, Lee Classic cast....?
Corbin's swaging books go into that in detail. Explaining force needed, how it's generated, maximum force possible with different presses and how much force is required to break a die.
Copies are out there, if you are interested in getting into swaging they are a valuable resource.
Ken
the bigger the bullet, the more pressure needed.
I checked on corbins palce but can not find the info, can you be more specific?
Corbin sells the info in book and CD form. They mostly cover required pressure do do various things, as apposed to 'pressure' available on an individual press platform. For one thing, many variables change the 'pressure' number, like diameter of the punch, bench flex, strength or weight of the operator etc.
I think what you're really interested in is available mechanical advantage. Those numbers are calculable based on press geometry, though I don't have any reference available off the top of my head. I suspect there are some discussions on that to be found on various reloading forums.
So no one has an idea (I´ve on many internet places, sites, forums); I understand that punch diameter, arm lenght and such variables impact the output but it seems no one has a real idea on the range or maximum amount of force achievable with a reloading or swaging press.
The only way to know for sure is to use a compression gauge in the actual press, and then measure it at the top of the stroke. This would be something an engineer would probably do, and the average reloader or swager isn't set up with that kind of equipment. I don't have any idea what that type of measuring device would cost, but I'd rather spend whatever it is on reloading and swaging components and tools.
Hope this helps.
Fred
The only time I have actually measured psi at the end of the punch that was doing the work was on my RCE HydraSwage when extruding lead wire. Based on the actual pressure at the head of the ram, I was able to calculate psi at the head of the punch using simple proportion. Knowing the cross sectional area of the ram and the cross sectional area of the punch, pressure to extrude my .249 wire was about 37,000 psi. This pressure would be higher for smaller wire and lower for larger wire. These pressures were only achievable with a hydraulic press. I may have achieved similar pressure at the very end of the stroke of my Rockchucker II when extruding short lengths of .250 wire using a die a member here made. A 300gr 44 Mag bullet made about a 3 inch length of wire. By screwing the die down a little at a time, using the end of the stroke, I could make the wire.
Bob
OK. so there´s is some first hand info, thanks
It's true that Corbin sells his books, but there is also a free version which you can look at here: http://swage.com/ebooks.htm
They aren't the most recent version, but recent enough for your intended purpose.
Quote:
Originally Posted by NoZombies
I checked them and there are no real numbers (psi) on any of them, you get the same answers as here. Midnight is the only one (so far) with measured readings (no doubt Corbin has unpublished real measurments), the rest are speculations
If you are looking for measured mechanical advantage then you are going to have a tough time finding that.
The early, first real, reloading press is the Pacific and it has a known 4 to one ratio that is constant over the arc of the handle swing.
Swing link designs pioneered by RCBS have a variable ration over the arc of swing and are not easily calculated. Some of the variables are the length of the arms, the length of the handle, and the offset of the pivot block. And these specs vary greatly by press model and brand.
I have often wondered what the ratio was for the RCBS A press and the Rockchucker, but RCBS is tight lipped about sharing it.
If you really need to know then finding a good mechanical engineer who is willing to take the time to work it out for you is advised.
The generated pressure in a swaging press has been always a question in my mind (I swage slugs for my air rifles, had a lot of fun following the forum plans for a DIY swage press). Unfortunately I don't have an engineer at hand (I'm a Veterinary Pathologist, that kind of equations are out of my league). It's easy to understand why is not an easy equation (lots of variables), but I was hoping someone had an idea...
I don't have actual numbers but I do know when the handle falls on my BIG MAX , and my finger gets squeeeeeeezed I quickly resort to PSI conversion = Proffessional Swearing Incrementually the harder the sqeeze the longer the profanity goes
We have ALL pinched fingers...... OUCH!!
Yes it happened to me once, one finger only, my PSI skyrocketed
The hexagonal press made by Herters is called a 9 ton press, others have made presses similar in design.
You might consider reading the book on power swaging. Corbin's hydraulic press is fitted with a gauge which shows hydraulic line pressure. He goes to some length to convert that pressure to the actual pressure being exerted in the die. Not at all just to know it, but to be able to know when it's too high for a given die caliber and that you should stay below it or you will crack your die. I realize you probably don't have a hydraulic press, but many of us do. If you have a particular caliber in mind, perhaps we could tell you the line pressure for a given operation and you can then calculate the die pressure if it's important to you. It varies for each operation, core swaging is different than core seating which is different still than nose pointing.
Hope this helps.
Quote:
Originally Posted by kimoleto
Yes Zbench is a good idea, as I said before I swage slugs for my air rifles, 22, 25, 30 and 41. If somebody has the equipment and wishes to help it may solve my (dumb) question.
NOT a really good answer - but GONRA has always figgered (in my percussion primer verk)
if a home made "mild steel" punch deforms yer (maybe) around (at least) 60,000 PSI.