Home made dies

[KTN]

Martin,

If next few days go nearly as good as today, I will have finished point forming die in my hands on Friday . After lapping that die for two hours today, most of the scratches were gone and measuring .2415" now.
I will use .22 RF and .22 WMR cases for jackets as my goal is to make cheap bullets. But I will try making jacket drawing dies later.
Just one little problem with with 6 mm bullets, I don't have gun for those .

Keep us posted on your progress with .30 boat tail dies.



Kaj

[martin]

KTN,

In your last post, it sounds like you are well under motion for your point forming die - how did it turn out?

If you were at .2415 I imagine it took quite a bit of lapping to get to .244. It takes me roughly 2 hours per thousands when rough lapping and a lot more when I work my way up to 3000 grit.

You also stated that you were going to use spent .22 rim fire and .22WRM for jackets. My experience is that both of these are fairly thin. I think that you may find that they work ok for velocities less than 2800 fps but when you go above that, you may run into some problems that they don't stay together. I have seen some at higher velocities that produce a vaper trail and explode before they make it to a 100 yard target at between 3300 and 3400 fps out of a 223. I would think that in 6mm the jacket would be even thiner but hey, give it a go and let us know how it works out.

Your little problem not having a 6mm to test your projectiles in, I have a solution.... this is a good excuse to aquire one. You had mentioned in one of your previous postings that your home country was rather restictive - is there a limit on the number of firearms you may own?

My 30 cal dies are coming along slowly. I wish I could spend more time on them but there seems to be more chores to be done now that the weather has warmed up a little.

Martin

[KTN]

Martin,

I'm getting close .2425" right now. I need to make few more parts for these 6mm dies and for other projects before heat treating and final polish.
My other projects that I make while taking break from lapping are swaging press, wire extruder, case trimmer and trying to design jacket drawing dies.

Even thinking about gun laws is bad for my blood pressure, but I tell to you anyway.
There is no LAW limiting how many guns I can own but our version of ATF called AAHY keeps making rules (against law) that say I must NEED that gun, and if I already have similar gun they can rule that I don't need that gun and not give me permit.
Would you believe that only 10-15 years ago it was much better?
If I wanted to buy rifle or shotgun in those days, all I needed to do was to go to permit office on my local police department, fill the form, they check my background, pay tax and walk out with permit to buy that gun.
For pistolpermit it usually took 10-20 minutes interview with the police officer who was incharge on gun permits, fill form, pay tax and walk out with permit.


And then SHTF, Jokela school shooting in 2007 and Kauhajoki in 2008.
Now it's VERY hard to get permits for long guns and almost impossible to get permits for pistols.
But I'm still little optimistic. Elections are coming and there are 600000 gun owners in population of 5.5 million and all are voters.


Kaj

[Bullet Head]

Where can I get unhardened O-1? I was thinking about Mcmaster Carr but it looks like all their O-1 is already annealed. Annealed and "hardened" is the same thing right?

I'm not any sort of machinist but one guy I talked to who claimed to be a machinist said I couldn't make this kind of die out of annealed O-1 because it would be too hard to machine.

[Houndog]

Where can I get unhardened O-1? I was thinking about Mcmaster Carr but it looks like all their O-1 is already annealed. Annealed and "hardened" is the same thing right?

I'm not any sort of machinist but one guy I talked to who claimed to be a machinist said I couldn't make this kind of die out of annealed O-1 because it would be too hard to machine.

Annealed means in it's UNHARDENED state. The salesman probably has NO machining experience to come across with a statement like that! O1 doesn't machine as easily as leaded cold roll, for example, but it's no harder to machine than many of the other tool steels. I use A2 for dies because it holds it's demensions better in heat treating than O1, and it's easier to heat treat, but there's a bunch of dies made from o1 every day.

[scrapcan]

YOu can get the tool steels in 36 inch lengths from Enco. They have a little sale going on right now and if you look around you might find a free shipping on orders over $25.00. They have oil and air hardened on sale, but carry other types.

[Fred T]

Gentlemen
pardon me for butting in, I am absolutely new to this forum but have been making stamping dies and precision gages and fixtures for most of my adult life. Cutting tools as well, I think KTN is doing an awsomem job with the pointing reamers. My original boss would be impressed! From reading through this whole chain I se that most are having difficulties in their reaming on center in a lathe. What I do when I need absolute precision is to drill a hole that is .007 PER SIDE smaller than the finished ream size. It is important to have enough material to make a chip out of. Make a tiny boring tool that will fit in the hole and bore it about .003 shy of finish diameter and about .1 deep. Install a live or dead center in the tail stock clamp either a tap handle or a pair of vise grips to the reamer shank near the tail of the reamer. put the chamfer of the reamer in the undersized hole you just bored, bring up the tail stock center to the centr in the back of the reamer. MOve the tool post so that the tap handle or the vise grips are resting on the tool holder. Oil the reamer, I try to use that black stinky oil, we always called it black tom, it is really sulferated cutting oil though. anyway use the tail stock to push the reamer. It will follow the hole that you bored, the boring makes it on center. Remember to turn the lathe off before removing the reamer from the workpiece, this is something that you will only forget to do once.
God luck
Fred T

[martin]

Fred T,

Welcome to the group and thank you for the information on how to get a good centered hole in a die. It sounds like you have a fair amount of experience in the tool and die area.

There is a question that I have had for a while and maybe you could provide some input from you perspective: I have always thought that there was a better way to make dies and that is with a plunge EDM. I understand that the process would yield very smooth holes that would be within .0005 of the final desired dimension and that it could create these in a much reduced amount of time (compared to reaming and lapping).

In your work, do you have experience in EDM and is this a better method than reaming/lapping? Would there be an advantage to starting out with a hardened piece of tool steel to do this with?

Martin

[mactool]

If you edm the die, you would still have to polish it, unless you have an unlimeted funds which can pay for the electro polish in the edm maschine. second, another factor is that you have to stress relieve the die after the edm operation at a temp 60deg belov the annealing temp for at least 2 hours. Third you have to make the finish electrode 0.001-0.0015 smaller than the wanted contour, and the surface finish must at least be as smooth at the finished bullet is supposed to be, Im talking of a surface finish of Ra=1.2(0.00005")

[Fred T]

Martin
I have limited experience with a carbon edm (Sinker), I used to make electrodes and run an edm but that was years ago, right after they invented electricity it seems. Anyway I know that technology has come a long way and it is indeed possible. Have a look at a faceted tail light lens on some of the newer automobiles. Those are cut with a "sinker" then polished to probablly a #2 diamond finish. What they look like right out of the machine I couldnt say. I will leave that up to someoe who uses a newer model than the one I used to run. What mactool says about making the electrode a little smaller was definately true in the early eighties, I can't say these days.

[Bullet Head]

Who says dies have to be round? Could you take a block of steel and bore out the right size hole on a mill? Isn't that how they do engine cylinders?

I was just thinking of unthreaded shapes for a die since I was going to try swaging on a arbor press.

[Bullet Head]

I talked to Dave Corbin the other day and he said that his dies are heat treated overnight. Any good ideas for how am I supposed to heat treat my dies? How would they do it in the "old days", charcoal fire perhaps?

[ANeat]

Bh how you heat treat will depend on the steel you use.

Heat to a certain temp and let soak for a bit, 10 or 15 minutes. Quench as required by the material and temper to the required hardness

[jmh54738]

I talked to Dave Corbin the other day and he said that his dies are heat treated overnight. Any good ideas for how am I supposed to heat treat my dies? How would they do it in the "old days", charcoal fire perhaps?

Dave means that he gives the die to the heat treater and he gets it back in the morning. I've done this for years, marking the steel type on the die parts with felt pen (also stamped). In modern vacuum furnaces the felt pen marking is still visible after hardening and tempering. In the old days the choice of tool steels was limited; the blacksmith heated the steel until it no longer attracted a magnet (upper critical temperature) at which time the steel was quenched in either oil or brine. After a polish, the die was tempered by color as it was reheated. The color depended upon the use of the tool....light straw is hard and brittle, blue will add toughness. Beyond full blue the color will fade. A chisel would be tempered beyond blue of the striking end and perhaps dark straw on the cutting end. Various compounds are available to prevent scaling when heating in an open fire or a atmospheric furnace. Stainless steel foil wrap is also used to prevent scale.

[Bullet Head]

I'm using 2" diameter W-1. Going to build a little non magnetic stand that dangles a magnet so I can tell exactly when the steel stops attracting a magnet.

Is the scale forming in the furnace or at the time I quench the part?


Thanks to tidewaterblacksmiths.net

[*MALICE*]

I wanted to post some advise for everyone about reaming holes. This may or may not help you as it is somewhat dependent on the type/capabilities of the machine(s) you are using. My experience is with CNC machines.

I've noticed that some people are getting scratching or poor surface finishes when they ream their dies.

A good idea is to use two reamers. Drill the hole approximately .015" undersize, rough ream to .003-.007" undersize, then finish ream to size. Feed in/then feed out flushing with coolant. Feed the same as you would when drilling and drop your rpm to around 2/3 what you would for an equivalent sized drill.

A lot of people retract the reamer from the part to clear the chips. Sometimes this works okay, but mostly not. A better method is to use water soluble coolant to flush the chips out of the hole (either through the tool or flooding around the tool) as they are being made and not start/stop your cut. Starting and stopping will produce inconsistencies in the finish that you'll only have to polish out later. As well, it gives your tool a chance to move off of it's intended path. Once you start a cut, don't stop until you finish it.

Chamfer the hole before reaming (holes to be tapped should be chamfered as well), make the chamfer match the chamfer on the end of the reamer. You don't want an uneven burr from drilling to push the reamer off center.

Some people I know hold reamers in a chuck. I don't. Reamers are often very long and the longer they are, the more vibration they are prone to and the more likely they can bow which will cause an oversize hole, chatter and bad surface finish as well as prematurely ruining a possibly expensive tool. I hold them in collets and choke them up just passed where the fluting in the shank ends. Everything should be held as rigidly as possible.

I hope any of this helps anyone. I should also say there's no one 'right' way to do things, so, if you have another method that currently works fantastic for your needs, keep doing it. Fred T's method is pretty good if you're using a manual machine, and the only improvement I would make is flushing with coolant instead of using oil.

[jmh54738]

Bullet Head, the scale is formed while the part is in the furnace. The common type of muffle furnace should have the air/gas mixture adjusted so that a flame is standing out of the exhaust holes thus indicating a fuel rich atmosphere as opposed to an oxidizing atmosphere where there is too much oxygen present which will cause scale. Although I have not tried it, coating the part with a paste of Boric Acid, I have read, will shield the part from oxidation. Royal casehardening powder would be a good choice to use with your W-1 as a carbon source, it will prevent surface decarbonization and also eliminate scale. Hope this helps.

[Bullet Head]

Thanks for the tip. Hopefully I won't have to try this too many times before I get a working die. Another tip I just read was to coat the part in the black soot you get from a acetylene torch without the oxygen turned on. It should leave a layer thick enough to stop the oxygen from attacking it during heat treating.

[ANeat]

Thanks for the tip. Hopefully I won't have to try this too many times before I get a working die. Another tip I just read was to coat the part in the black soot you get from a acetylene torch without the oxygen turned on. It should leave a layer thick enough to stop the oxygen from attacking it during heat treating.

No I think the soot will burn off at about 900 degrees

[jmh54738]

I agree, the soot just won't do the job. I have made a lot of dies out of mild steel and hardened with Royal hardening powder. When water quenched the steel comes out grey, clean and no scale. Can't be scratched with a file. The case isn't very deep, but who cares.
John