Jacket making Need help

[waydownsouth]

Has any one had any experiance making bullet jackets
some pictures of the dies used would be great

Myself and one of the fitter and turners at work have been trying to make bullet jackets without much luck.

we have made an experimental die and punch and have been using it in a 3T arbor press

The problem we are having is when we try to swage a jacket the material folds
The only stuff we had laying around the workshop was brass shim which we anealed is this our problem and will using copper sort this out ?

8888

We did have some sucsess with a heap of grease and slideway oil as lube a smaller punch and a gentle touch we made one that kinda looked like a jacket

8889

next we tryed a smaller disk about the right size for a gas check and still had the same problem though not as bad but it still looks like a bottle top

8890

will post a picture of the punch and die tomorrow (left it at work)

[wonderwolf]

Check this out this may or may not help you but they cover some of what can be done to make good jackets out of strip material. http://bulletswage.com/jackets.htm#strip

[docone31]

I once saw a vast picture tutorial on making jackets, then swageing the lead.
If I remember correctly, the jackets were drawn rather than jammed. The jackets went through several dies to form the cups. There might have even been another annealing step involved.
Copper, rather than brass might indeed help, that might be why bullets are predominantly swaged in copper. It can be really worked.
Once again, if memory serves me, The primary cups were formed, then, with the lead slug, finished swaged. There, on the hollow points were four leafs that were formed into the point.
I believe it might have been an article from Speer. It was in a magazine. I had always wondered how they got the lead into the jackets. I had somehow thought they vaccumed liquid lead into it.
Back when I was a spinner, I used to spin brass, and copper and pewter. Brass had to be annealed several times during the spinning steps. Copper I could form the part and be done.
I have always been interested, I might do a search on making bullet jackets.
You never know.

[docone31]

Here is from a quick search.
http://www.corbins.com/tubing.htm
This gives the most in a small package.
They are drawn from copper tubing. Obviously, copper tubing is way too thick so it is drawn. From there, the swageing begins.
You could draw tubing by spinning it over a mandrel. The spinning, will thin the metal as the jacket is formed, then annealed, cut, and swaged.
So simple to say, I do wish you luck. This is what I had wanted to do, so many years before.

[jcunclejoe]

To make the cups you need to hold down the outside of the disk. This must be done with considerable pressure using a round cylinder, that is as big as the disk on the outside and the size of the punch on the inside. On a production press they use a double acting press station, one to hold down the disk and then the punch in the middle draws the cup out pulling the material out from under the hold down ring/bushing/die or whatever you would like to call it.
It might be tricky with an arbor press but certainly not impossible using a heavy spring around a long enough center punch.

Joe
(former) Nosler tooling engineer for over 6 years.

[waydownsouth]

Thanks for the help joe i think you have just pointed us in the right direction. The arbor press was used only because it was the quickest press to play with at the time we do have acess to a couple of other presses that may be more suitable for the job.

Can the jacket be formed in one step or is it only partly formed and then finished of when the core is seated and i guess trimed to the right size some were in between ?

What size copper disc should we start with in relation to the finished jacket, how much will it be drawn ?

Heres is the die and punch we were using please excuse us for the rough job but they were made up in about 20 minutes before work started for the day.


8912

8913

[sav300]

That set of tools may swage the rim off fired .22 brass if the right diameter.
Interesting thread

[waydownsouth]

That set of tools may swage the rim off fired .22 brass if the right diameter.
Interesting thread

yes with the same basic design you can swage the rim of .22 rimfire shells the dimentions you need are .223 for the inside dia of the die body and .197 for the punch.
heres a picture of one i made up for my reloading press

8924

the punch on the left mesures .195 and dose not fully swage the rim off it leaves a ring where the rim used to be also it is a bit long

the punch on the right mesures .200 it is a bit tight and 3 out of 5 times will punch a hole through the shell but it is about the right length for my press


on our lunch break we had a bit more of a play trying to swage jackets and had a bit more luck with a bit more taper in the die body and a punch with a rounded end we also used copper the result looks promising

the fitter also built a die and punch for cutting out 1 inch discs of copper

[jcunclejoe]

waydownsouth
Those are pretty tough questions to answer in any kind of short manner. The size of the disk depends on the desired jacket diameter and length and by the jacket shape. Do you want straight (equal thickness jacket walls) or jacket walls that taper thinner toward the mouth end? It usually requires several steps to get a finished jacket. You will have a blank or disk cutting step, cupping, then 3-4 draws depending on length, then possibly a bell station (if you are going to pinch trim) then pinch trim. Then you can start making bullets The step where you seat the core will expand the jacket to just below finished jacket diameter. Then in the final form station you will expand the jacket to final dimension. A production press for making jacketed handgun bullets usually has about 15 stations. Of course a hollow point punch would be in there somewhere if desired.

It is very difficult to make a jacket in one step unless you want one wide and short like one for a 170gr 44cal and I doubt that would produce satisfactory results.

As far as how much will it draw? just think about the diameter of the die always being constant and would equal the outside of your jacket in that station. Then take the profile of your punch and put it in the die and the amount drawn would be the difference between your jacket wall thickness minus the punch profile. I always design everything as a perfect cross section so I can see what is going on between the punch and die. The volume of material is maintained from station to station and that helps tell you where the material must go.

I could teach you a ton in a day if you were here with my computer or me there with a drafting program. The design of the tooling is quite complicated and full of little tricks.

I'm not trying to run you off from the project, but it is very involved. I hope this helps some.
Good luck,
Joe

To answer one more question, using copper will help, annealed brass is good but will work harden faster than copper.

[waydownsouth]

Dont worry joe i dont scare that easy, complicated i dont mind and trying to work out the little tricks the hard way is the fun part .
to be able to form a jacket with a tapered wall would be a real bonus but not nessesery, but i would still like to know how it is done.

To form a tapered jacket is the final draw done with a tapered punch or is there some other little trick involved ?

the brass shim was only used because thats all we could find laying around in the work shop. after a breif chat with one of the tin bashers we found a small sheet of 0.5 mm (20 thou ?) copper which we cut some 1 inch disks out off.
with a new punch and die we had another go and formed a big round base cup, i think we are heading in the right direction now.
heres what it looks like

8925

[redneckdan]

if you can get me some data on your shim stock I can run some number for you. One professor here I work with does research on single pass deep drawing. I do most of his tool making.

[docone31]

Hey!
I bet he is going to make it!
Good for you.
You will have to post a full picture journal when it is done.
Go for it.

[cabezaverde]

I just picked up some Hornady Pistol Cups at a funshow. Look like oversized thick gas checks. Anyone know anything about these. Do you mold a core, or how do they work?

[jcunclejoe]

You can put the taper into the jacket on the final draw or you can begin it sooner if you like.
Just draw a cross section of the finished jacket including the taper. THe inside is the shape of your punch and the outside is the diameter of the die. Just allow about .001 for the final form station to bump the bullet up to size. and at least .002 for swelling in the core seat station.
That will give the jacket at least .003 stretch to help lock onto the core.
That cup looks way better.
A recess in the top of your die will help keep the disk centered and the hold down will keep it drawing evenly.

Looks like redneckdan will be an excellent source of information.
Maybe we can let the professor finish the research and then all of us get together to make our own bullet company?

Good luck.
Joe

[floodgate]

cabezavrde:

What caliber are they for, and how tall? They can be used with the C-H Swag-O-Matic to make half-jacket bullets IF they are not so tall as to cut off the bleed port. Cores can be cut from lead wire or cast in an Ideal core mould like the "45 S" one discussed here yasterday. Lots of info here onthe swaging forum.

Floodgate

[Buckshot]

.............I know that cartridge case drawing is a multi step operation with washings and annealing thrown in for good measure between some steps. While forming a jacket from a disc is no doubt similar I'd be astounded if it was done in one fell sweep, one swell foop ......... all at once! :-)

I'm also pretty sure the dies are made of carbide, or at least have a carbide ring up top that is undoubtedly polished to a mirror finish. Any tiny little microscopic imperfection in the copper disc will be stretched and magnified a great deal before the deal is done. However you initial steps seem to be in the right direction.

It will be very neat to see your progression and eventual success. Please keep the info and pics coming!

...............Buckshot

[waydownsouth]

heres a picture of the disk cutting die we made up, i think it is 4140 but can't be sure it was an off cut from another job, once we work out what size disk is needed we will make the real thing out of k245 or something similar and heat treat it. at this stage a 1 inch will do.
the plan is to make jackets for .30 and .224

8932

we have given up on trying to swage a jacket in one step from our experiments i dont think it is possible

not sure about using carbide for the dies but some sort of case hardened material like en36a should do for working copper. i did see a couple of tubes of polishing paste i think they went down to 1 micron, so the final finish shouldnt be a problem.

[jcunclejoe]

Carbide is very commonly used for the draw dies, but the punch and die must be fully supported to keep them in perfect alignment. Any side load will chip or crack the carbide. The only trouble is that the carbide has to be ground then polished, can be quite expensive. Good tool steel works great but will not give the same life but can still last for a million parts or more.
Joe

[waydownsouth]

i think we got it this time, it took 4 steps to get a jacket that i think we can use
final jacket is just under .30 and has a wall thickness of 20 thou with a slight taper in the jacket wall

8978

here it is beside a .30 cal 130 gr speer, yes it is short, no it was not planned we under estimated how much it would draw out and had to cut it of the punch

8979

next thing we are going to make is a propper die set and maybe a press to use them in. we havent decided the final design of the dies, we are thinking of building a die plate with the punch built into it. by doing so will make sure they stay in propper alignment at all times

[jcunclejoe]

Now you are on track. If you like, you could increase the diameter of your draw punch by changing the angle, toward the upper 1/3 or so of the jacket. That would iron the jacket more, thin the jacket, and draw it out longer with the same amount of material. Of course, your stroke length must be able to handle it. You might also consider some mechanial strippers to pull the jacket off of the punch for you.
If your jacket tops come out a bit wavy, that is perfectly normal. A trim of some sort is expected.
Good work.
Joe

[waydownsouth]

joe some help with the design of the mechanical strippers would be apreciated , at the moment we are having trouble removing the jackets from the punch. the dies we have made to experiment with are not fixed and only work on the down stroke, but we are in the process of designing propper dies for the job.

will the jackets spring after they have been pushed through the die and if so will a square sholder be good enough to strip them of on the up stroke?

[jcunclejoe]

The square sholder on the top of the jacket will work for stripping. The jacket will spring back some but very little, and of little consequence. A great stripper can be made by drilling a hole the size of the punch in a 1" wide strip of material then cutting it in half, crossways through the hole. Heat treat the strippers. Then you will just have to rig up a lever to guide them in from opposing sides after the jacket goes through the draw die and before the upstroke. If the die is not very tall (more like a ring) you can have the strippers on the underside so they are supported (backed up) by the die when the jacket comes back against them.
In this set-up you will need enough punch length and stroke to go clear through the die.
Do not let the strippers touch the punch very hard or they will groove it fairly quickly.
Something as simple as a pair of pliers with the strippers attached and a mounting pin through the center of the pivot pin of the pliers to locate.
Keep after it.
Joe

[Rocky Mountain Bullets]

The design Joe expained is about the way we built our jacket draw dies, we make the stripper fingers just large enough to clear the punch so it dosn't get scored. The fingers ride in a slot on top of the die with a spring around them so they expand out on the up stroke and grab the jacket on the down stroke to strip the jacket off. Really simple and works good, sometime after a few thousand jackets the finger get some copper slivers jamed up and need to be cleaned. If I have some slack time in the shop tomorrow I try and take a pic for you.

Rocky Mountain Bullets, LLC
George

[Rocky Mountain Bullets]

Oh, I forgot to menton. Put a slight taper on the bottom side of the striper so they will open up easy when the punch and jacket go up through the die and engage the strippers.

Rocky Mountain Bullets, LLC
George