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View Full Version : Swaging warm-up for precision.



aaronraad
04-25-2015, 01:49 AM
Just two thoughts I've had following an email to another forum member today and some advice I received from a gunsmith in NZ this week. I figured this might be worth sharing with members and I think any comments relating to ones own personal experiences could add real value for other current members and those looking to make a start into swaging.


1) Why you shouldn't overlook a warm-up period when core seating or point forming. I've often read about the number of bullets (25 - 75 or x%), by those that have been willing to share their step-by-step precision swaging processes, designated as reject/varmint/barrel burners generated during the starting period they often describe as 'warm-up'. Typically this is described as a period where the die and/or press itself 'warms-up' and will take on features such a consistent stroke, diameter or meplat diameter etc. through the true production run of 'keepers' that require match grade target accuracy, for whatever reasons. So the discussion of 'warm-up' often points to our swaging equipment and tooling, but I believe the 'warm-up' period also has a lot of merit for the hand swager themselves. In part you also have to believe that the hand swager brings an element of 'feel' to the swaging process that automated pressing can't duplicate, without expensive precision sensors designed into the equipment and tooling.

So I believe that during the warm-up period, when you're making final adjustments and looking for correct (visual and measured) seating pressures, lead lines, boat-tails and meplats etc., you also need to be focusing on the tolerances of what feels right and wrong when operating the press. If you haven't swaged with that particular die set-up for weeks, months or years even, you have to have some form of incredible muscle memory to step-up without any warm-up and become that human gauge free from error, distinguishing all false bullets ejected from the dies without hesitation.

I believe that most humans need that warm-up period and for some it may take longer or shorter than others to get that 'correct' feel back. It can also be about finding the most comfortable position that produces the minimal and hopefully insignificant variances in your final product. I've found simple things like a change in footwear or brand/texture of mechanics type thin nitrile coated gloves I use, require some time to adjust on my part or 'getting use to'. For a while there I thought I was getting a little too precious or "Princess-and-the-Pea" if you like, when I felt a great amount of relief in removing what was nothing more than a piece of lead wire bleed weighing <0.5gr stuck between the out-sole of my 1" thick polyurethane foam footwear and the carpet on the workshop floor where I was pivoting my feet while swaging.

Distractions such as these deteriorate your ability to focus on what your feel if you're trying to swage with the most precision possible. Tragic I know, hardly the image of tough mountain climbing shooter braving the winter elements, or even the hardened gunsmith with calloused hands the size of dinner plates, straining to listening to the sound of metal cutting on his lathe to adjust the feed rate while watching the chip formation. I wouldn't discount a certain amount of physical strength, given I've seen a 12yr old boy put their full body weight behind my press and still not be able to point form, but the 'toughness' if you like comes in the endurance and being able to repeat that over your production run. You also need that certain amount of sensitivity to know when you're too tired to be repeatable and to stop and rest, or pack it away for the night or another day.

So I'd suggest that you should also remember to warm yourself up while you're warming up the swaging equipment and tooling.

2) You're allowed to make mistakes, especially in you're own workshop. We've all heard that part of being human is making mistakes and there is obviously a lot of human that goes into hand swaging and probably even more so into the tooling we use. There is no award or bragging rights for swaging the perfect projectile first up and quite frankly I don't expect anyone to do so. If you can't afford the cost of making mistakes while swaging, you've really got to ask yourself if you're into the right hobby. You have to give yourself time to learn and we don't all get the opportunity of one-on-one hands on training on our own equipment before we start using it. We might have written, verbal and video instructions but they really have their limitations when applied to hand swaging which is very much hands-on feel. Factor in people's preferences for learning across the common methods (visual, auditor and kinaesthetic) and you can understand why swaging doesn't hit the mark straight off the bat for everyone. One of the great attributes of being human, as opposed to machine (although AI is starting to get there), is our ability to learn and so to learn in part is to not repeat your mistakes...intentionally anyway ;)

Conversely there are no bragging rights for making the most mistakes/rejects. I always liked the John West tag line "It's the fish that John West reject that makes John West the best.". The slogan doesn't go into how many John West reject but they admit not every fish they pull out of the sea is up to their standard. During a conversation with a local bullet die maker and swager, he described a tour of the US he made during the 1970's during which time he had a chance to visit with Ted Smith at his workshop. It wasn't until he saw Ted Smith's workshop nearly completely covered, inches deep in rejected hand swaged bullets from experiments, trials and testing that he felt he had met one of two people he described to me as a true 'gun nut'. To give you some idea of how much respect this 85yr old applied to the term 'gun nut', the other person he applied the term to was L.E. Wilson after he had the opportunity to meet him also during one of his US tours decades ago.

So if you're learning, you might still be making mistakes to the very end of days, hopefully though they well be less frequent and produce a smaller number of rejects each time. :)

Here's hoping this post makes some sense to at least some one? ;)

kweidner
04-25-2015, 05:11 AM
I feel you. I made a huge run a couple months ago and have been working on load development and a pet project. Needed to run some 30cal 167 this week and oddly my settings were an 1/8th of a turn out for the correct expansion. I think it was just as you described. I had a bit more variation in core weight than usual and chock it up to.........I need to sell more bullets so I don't get rusty lol.

R.Ph. 380
04-25-2015, 11:49 AM
I sure appreciate your thoughts. I'm just a "babe in the woods" in that I'm just starting my swaging . Over the past few years, I've read just about everything posted in the Swaging, casting and reloading forums. You have been the most consistent and informative in your postings, and I appreciate the help you have given. The machinists can give us the mechanical and tools necessary, but the everyday information and support is what makes it possible for us to succeed at what we are building. Thanks Aaronraad and all the other swagers on here.

Bill

just bill
05-12-2015, 04:51 PM
1) Why you shouldn't overlook a warm-up period when core seating or point forming. I've often read about the number of bullets (25 - 75 or x%), by those that have been willing to share their step-by-step precision swaging processes, designated as reject/varmint/barrel burners generated during the starting period they often describe as 'warm-up'.

I am a little miffed at the classification of barrel burners. There has been a lot of technical info and experienced observations in this and the cam-over articles. I realize there are factors involved when pressures are applied and we try to make our efforts constant. But the question that still makes me scratch the bald spot is " I have a fairly constant core weight +/- .1 and a jacket that is +/- .1 gr which in the best and worst case +.2 or -.2 per projectile. How do i know the 1st isn't as good as the 15th? If I follow the same procedure each and every time as close to humanly correct. Forgive me if this seems redundant, however maybe this is one of the times I am over engineering the whole idea.

Bil

xman777
05-13-2015, 04:26 PM
A thing that I try to do is have a visual check. If it just looks off, it goes in the plink pile. I couldn't tell you exactly if will fly as straight as the others but I can tell you it will most certainly fly. When I am plinking I may not be aiming at all, but rather popping rounds in delightful flurries. You'll just never know which one is better than the other. Don't read too much into it just bill.

just bill
05-14-2015, 05:26 PM
Any one have a clue where these heater pads, other than Lyman/RCBS ones for the sizer/luber, are? I saw an ad for poly flex ones for up to 400 f, first a little over kill. Second they didn't look as if they were capable of being drilled for mounting a Rock chucker.

Bill

aaronraad
05-15-2015, 01:33 AM
1) Why you shouldn't overlook a warm-up period when core seating or point forming. I've often read about the number of bullets (25 - 75 or x%), by those that have been willing to share their step-by-step precision swaging processes, designated as reject/varmint/barrel burners generated during the starting period they often describe as 'warm-up'.

I am a little miffed at the classification of barrel burners. There has been a lot of technical info and experienced observations in this and the cam-over articles. I realize there are factors involved when pressures are applied and we try to make our efforts constant. But the question that still makes me scratch the bald spot is " I have a fairly constant core weight +/- .1 and a jacket that is +/- .1 gr which in the best and worst case +.2 or -.2 per projectile. How do i know the 1st isn't as good as the 15th? If I follow the same procedure each and every time as close to humanly correct. Forgive me if this seems redundant, however maybe this is one of the times I am over engineering the whole idea.

Bil

In terms of barrel burners you are typically only talking about projectiles ejected from the point form die, as opposed to any out of spec swaged or seated cores.

This pretty much turn into another topic - What quality controls do you have for your swaging processes...Which rods do you make for your own back?

At one extreme you have those that will accept anything that ejects from the point form die, seats into a cartridge case, cycles through their action and then ejects from their barrel muzzle. At the other extreme you have those using every non-destruction measuring device they can get their hands on to measure every single projectile they finish. This is actually done on some comparable commercial level, but until they develop and app for X-Ray metrology with 3D computed tomography (CT or CAT scanning) for smartphones, the technology is only really viable for those producing artillery shells (see current in-line quality control methods).

For me an example is the stretch you can get soon after setting up your point form die for long ogive projectiles. You think you have the best meplat and then all of a sudden they start 'stove piping' into the ejection pin hole. Adjust the external punch back the length of the stove pipe and I find I've gone the other way and my meplat has opened up too far. Now we all know how shrink fitting works when correctly applied but what happens at lower temperatures with dissimilar metals, with significantly different coefficients of thermal expansion and heat transfer rates. Well in my case, the complete opposite occurs when compared to shrink fitting as an application. One very hard stable die dumps it's heat very quickly into one very compliant copper(mostly) covered lead cylinder. I believe stove piping exacerbates this increase in heat, because of the extra pressure required to shove copper into a relatively small (0.063") ejection pin. Backing off the external punch removes the stove pipe, but also removes the pressure and heat added each time/stroke. So when I back off I will usually now do this in some increment less than the length of the stove pipe.

To some extent a similar event takes place during the core swage and core seating operations. More pressure and heat result in more bleed off and more bleed past the punch in the core swage die and the core seating die respectively. The changes aren't directly proportional to the length or mass that you are over, but you also need to consider any changes in the pressure and heat you are adding. This is also why changing the amount of lubricant can bring about dramatic changes in dimensions. This is why multi punch and die press set-ups laid out in series, don't react well to pressure changes and start spitting out defects at 120 units/minute.

Understanding the tolerances you have for your masses is important, but there are a number of other measurements which dictate the consistency of your finish projectiles. Jacket wall thickness, overall length and hardness can vary considerably for jackets of the same weight. Ever notice a core that sticks up higher than the others when just inserting them by hand before core seating? The core could be damaged, there might be foreign material in your jacket or it's ID is fractionally small. The list goes on depending of course on what your swaging.

aaronraad
05-15-2015, 01:54 AM
Any one have a clue where these heater pads, other than Lyman/RCBS ones for the sizer/luber, are? I saw an ad for poly flex ones for up to 400 f, first a little over kill. Second they didn't look as if they were capable of being drilled for mounting a Rock chucker.

Bill

I've used silicone heating pads branded as KEENOVO. The supplier I used makes them to whatever shape you like with a few voltage and wattage options as well. I sourced my own temperature controller and a solid state relay with heat sink to suit and mounted it myself in an enclosure. Most these are designed with a thermal cut-out at temperature X deg if you are not controlling them with your own temperature controller and thermocouple.

I believe it's the same resistance type wiring system used elsewhere in the world to prevent pipe work from freezing over, trace heating? Not a problem at my longitude, latitude and altitude.

I was in an electronics store today and the guy behind the counter showed me the little 12V 2" square ceramic(?) heating plate used in the heated coffee car travel mugs. They are selling them as a separate item now and a short experiment showed they get too hot to hold very very quickly.

I effectively just use a bracket to hold mine down to make as much contact as possible. You could also use something like the heat-sink paste they use for computer chips between the surfaces to get the best possible heat transfer. A few of the barrel type heaters are done incorporating a string ties, Velcro or elastic bands to hold them directly to the item.

xman777
05-15-2015, 11:24 AM
http://www.amazon.com/gp/product/B00858UVPI/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

These are the heaters I use. Just screw a plug on them and slide em over your dies. Instant satisfaction.

xman777
05-15-2015, 11:27 AM
139556http://www.amazon.com/gp/product/B00858UVPI/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 (http://www.amazon.com/gp/product/B00858UVPI/ref=oh_aui_search_detailpage?ie=UTF8&psc=1)

These are the heaters I use. Just screw a plug on them and slide em over your dies. Instant satisfaction.

R.Ph. 380
05-15-2015, 12:33 PM
139556http://www.amazon.com/gp/product/B00858UVPI/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 (http://www.amazon.com/gp/product/B00858UVPI/ref=oh_aui_search_detailpage?ie=UTF8&psc=1)

These are the heaters I use. Just screw a plug on them and slide em over your dies. Instant satisfaction.

Thanks

xman777
05-15-2015, 12:35 PM
That's WHY we're here.

aaronraad
05-15-2015, 08:58 PM
Good stuff xman777!


I was in an electronics store today and the guy behind the counter showed me the little 12V 2" square ceramic(?) heating plate used in the heated coffee car travel mugs. They are selling them as a separate item now and a short experiment showed they get too hot to hold very very quickly.

Thermoelectric (Peltier technology...I knew it wasn't piezoelectric?) solid state heat pumps.

http://www.jaycar.com.au/Active-Components/Other/Specialty-Active-Components/Thermoelectric-%28Peltier%29-Modules-68-09W/p/ZP9104

If I understand this correctly you can have a normal electrical resistance heater made with a ceramic element instead of metal, but these are different in that you have one hot side and one cool side for a heat pump effect (excuse my wiki):

http://en.wikipedia.org/wiki/Thermoelectric_effect

139588

P.S.: Looking forward piezoelectric acoustic generators. :)