My version of a Jacket Trim Die

[Rat-Man]

Just thought I would show you all a jacket trim die I made to make 45 grain 22 rimfire jacketed Hornet bullets.

The .70 length was just to long for a Hornet bullet , so these were trimmed to .575 which is about the length of some factory Hornet bullets that I bought.

I still have to make some to see how they shoot, so I will have to post pictures when I actually make a bullet with the trimmed jacket.

First is a view of the parts and the results.
http://castboolits.gunloads.com/picture.php?albumid=260&pictureid=1828

A view mounted on the press.
The knockout rod still needs some kind of top to smack with my hand to eject the jacket from the die, but it was made from a piece of 1/4 rod that was already tapped so I just stuck a screw in to use with a hammer for now.


http://castboolits.gunloads.com/picture.php?albumid=260&pictureid=1826

The cone shaped part in the shell holder with a de-rimmed jacket ready to trim.
http://castboolits.gunloads.com/picture.php?albumid=260&pictureid=1827

Now a closeup that shows how the jacket is trimmed to length.
http://castboolits.gunloads.com/picture.php?albumid=260&pictureid=1829


:mrgreen:
So now some of you have another new project to build.

[ANeat]

Hey thats nice Rat,

[sagacious]

Very clean work, Rat Man! Looks great.

I used an old wooden awl handle on top of my knock-out rod. It's got that wide, rounded shape that was designed to minimize stress on one's palm. Works great. It'd be easy to turn a similar shape out of a chunk of wood.

[Bullshop]

I need one. Where do I sign?

[DukeInFlorida]

So, you just squeeze the cone thing towards the other part, and it PINCHES off the brass?

[sagacious]

Yes. Commonly called a 'pinch-trim' die.

[ANeat]

Yea it looks like it would pinch it right off.

I can see the two guiness beer guys now.

BRILLIANT

[Rat-Man]

That's exactly how it works. There is a 5/16 sliding rod inside the die that is stopped by the threaded bolt that the knockout rod passes thru.
Once the rod hits bottom the brass can't go farther, so any sticking out is pinched. The knockout rod pushes the sliding rod inside back down ejecting the brass.

[BT Sniper]

Great work! Don't know why we haven't seen one before. Probably been mentioned but don't remeber seeing any, great pics.

[richbug]

This solves the problem of 22 mag cases being too long for 243s. nicely done.

[Rat-Man]

Those 22 mag cases are another reason I wanted to build one of these. I have about a full quart baggie of those that I want to use to make heavy .22 bullets but they are way to long.

I forgot what the length of them are but they look like a pencil laying on the reloading table

[CWME]

You are a Genius... Nice clean work there!

[DukeInFlorida]

So, here's the question (actually two questions):

What's the angle of the cone????

And, what is the steel used to make the cone and the trim die?

I see something similar on the Corbin page:
http://www.corbins.com/et-1.htm


I did some reading and see how it works, just would save the rest of us some time if you shared the angles, and tips for edges, and steels... Thanks

[Rat-Man]

Duke,

Glad to provide that information for you. The steel is O1 drill rod that is what I keep a supply of for various parts making. The piece in the bottom of the die is 3/4 diameter with about 3/8 inch 1/2-20 threads to screw into the die bottom, it is about 1/2 - 5/8 inch long total.

The cone is 30 degree included angle, but I think after using it a little that 45 degree might be better. When i trim a case the mouth looks like it is chamfered more than it needs to be.
This cone in threaded 1/4-20 on the back side to thread into a adapter that I made to accept various things that I make.

I will probably make another cone later just to try it out, and if I do it will be like a Lee push thru sizer punch with a 45 degre bevel.

Rat-Man

[scrapcan]

very nice. Thanks for the pictures.

for the push out you might look at building a spring return box. I think all of Swagerman's images are now gone, but I think you had a post in one of his threads so probably remember roughly what they looked like. Kenjudo can prbably assist also.

I had thought one could make a barrel that threaded onto top of die with a washer on the pushout rod and spring on top of it and inside of barrel. When you push the jacket/bullet into die it pushes the rod up and compresses spring, when you release the ram it hen uncompresses spring and pushes rod down and jacket/bullet out. Not sure how well it would work. I think you gould use valve springs to build one.

You could also look at a CH ejector. It fits the top of die and has a cam the rotates and pushes the rod down.

[Rat-Man]

manleyjt.

That's a good idea but I think that any spring that would automatically eject the brass would cause it to start expanding before going into the die mouth. It takes a smart tap with the hammer laying on the table to dislodge the trimmed case.

I did put a plastic knob thing on the rod and can hit it with my hand to dislodge the jacket then just push it till it falls out. I think I will end up with a plactic or wood ball on the ejector rod to just hit with my hand.

[garandsrus]

Rat Man,

Great idea! If you could answer a couple questions, I would appreciate it:

o How much pressure does it take to pinch off the brass? Is it similar to resizing brass?
o Does the trimmed piece (belled) slide right off the taper, or does it tend to stick?
o Did you need to "sharpen" anything?

John

[ANeat]

From the Corbin link that Duke provided it looks like you sould have the die set where it doesent cut thru 100% but leaves a thin section of brass, that way youre not getting steel to steel contact.

[Rat-Man]

What Aneat said is right. The rest of my reply is below


Rat Man,

Great idea! If you could answer a couple questions, I would appreciate it:

o How much pressure does it take to pinch off the brass? Is it similar to resizing brass?

There is very little pressure required


o Does the trimmed piece (belled) slide right off the taper, or does it tend to stick?


The one picture shows the belled brass with the bell attached. That is the way almost all of them come out, I just grab the bell with a pair of pliers and it snaps off.
That is the way it should work to avoid both of the hardened steel pieces hitting each other.
To set up the dies I just raise the ram and screw down the die till it touches the cone and lock it down. When the brass is between the pieces the press springs a few thousandths and leaves it attached.
If you set it where it pinches all the way through it will eventually screw up one of the parts



o Did you need to "sharpen" anything?
John

The only thing that is sharp is the corner of the hole in the bottom of the die

[scrapcan]

Rat-man,

I thinkthat if you make the spring box so it is shorter than actually pushing the knockout rod all the way out to the die it will give enough push to get the case moving. I don't think you will have to push it all the way out with the spring driven punch.

[garandsrus]

Rat Man,

Thanks for the quick reply! Very cool...

John

[DLCTEX]

Great work! Thanks for sharing.

[Rat-Man]

My pleasure. It's a small repayment of the vast amount of information that I have received from this site.

Rat-Man

[Rat-Man]

Just wanted to warn anyone that is thinking about building a pinch trim die about a problem that developed with the .22 lr brass jackets.
I started making bullets with the shortened jackets and the tips are folding.
http://castboolits.gunloads.com/picture.php?albumid=260&pictureid=1831

I know a lot of people don't worry about these but I am getting a lot of them.
It seems that even though the jackets are annealed the brass is brittle enough that the thin edge develops a crack that continues to grow as the point is being formed.

I built this trimmer to remove the bevel and get the mouth back to the approx .010 of the brass case.
http://castboolits.gunloads.com/picture.php?albumid=260&pictureid=1833

After trimming the mouth these are the results.
http://castboolits.gunloads.com/picture.php?albumid=260&pictureid=1832

I think that my next step will be to try a 45-60 degree angle to see if I can skip the trimming of the champher that is created with the 30 degree cone angle.
I think that a real jacket being a lot softer would not have this problem, but those are way too expensive to use for cheap shooting.

When I get around to trying a new cone angle I will post the results. If anyone else beats me to it, please post the results of what you were able to accomplish.

[sagacious]

Looks good. Re-annealing your trimmed jackets in batches is another labor-saving solution. I have found that a second annealing doesn't hurt the 22lr brass any, and tends to make the annealing more uniform per batch anyway.

Cone angle is something you can experiment with, but you can also make the trim punch with only a very short tapered shoulder-- like a Lyman M die for case mouth expanding. The tapered section need only be a few hundredths long to pinch-trim the brass. That will work the brass less, but you may find that regardless of punch angle, the real culprit is the cutting/pinching itself. That may cause enough work-hardening of the jacket-mouth by itself. Re-annealing will correct any potential problems either way.

Keep up the good work. :drinks:

[Rat-Man]

I tried re-annealing a few the first thing, thinking like you that it was work hardened. It didn't seem to make a difference, but removing the taper fixed the problem on both the re-annealed and the trimmed cases with out re-annealing.

I don't know what the final outcome of the cone angle will be but at least I can make some 45 grain bullets without to much drama now, because trimming .185 in length with out the pinch trim was a real pain.

[DukeInFlorida]

Right, and from the further reading that I did it's important to not kiss steel to steel. Doing so will immediately peen over the sharp edge of the die (not the tapered cone punch, but the die that the cone mates with)

Peening over that edge due to steel to steel contact will require re-sharpening the face of the die, or else the brass only smooshes (good word!) rather than cuts.


From the Corbin link that Duke provided it looks like you sould have the die set where it doesent cut thru 100% but leaves a thin section of brass, that way youre not getting steel to steel contact.

[jdjframes]

Nice work, looks like a Corbin unit.

I got all charged up to buy a Corbin until it dawned on me than I could buy a bunch of 22 Shorts for $250!

Jim

[Cane_man]

great thread from rat-man, anyone else try to make on of these pinch trim dies? can a trim die be made to trim 9mm cases?

[DukeInFlorida]

No, it's better to get one of the sets of cut off saw (harbor Freight) inserts from chuckbuster to do that.
I bought a complete set from him for adjustable length cutting of 9mm's, .40's, 45's, 5.7X28's, and 223 rem's. They drop in and out, and are adjustable for where they get cut. Makes the job of cutting the 9mm's down so very fast and simple. I owe chuckbuster a thread with pictures for this one.

The wall thickness on the 9mm's would be too thick for the pinch type tool.


great thread from rat-man, anyone else try to make on of these pinch trim dies? can a trim die be made to trim 9mm cases?

[Cane_man]

^^^that is what i thought, 9mm wall thickness was too much for a pinch trim die

[IllinoisCoyoteHunter]

Maybe chuckbuster could post pics and prices. I am VERY interested in sets for 9mm and 40 brass for the HF chopsaw.

[257]

I was wondering if you could post a drawing( sectional) of the die showing the parts in relation to each other don't really need dims. thanks

[Rat-Man]

I didn't make a drawing I just made it up as I went.
I will try and post a picture with the parts exploded, to help visualize how it works internally, in the next day or two though.
I didn't think about doing that originally!

[Rat-Man]

Pictures as promised.

Parts:
http://castboolits.gunloads.com/attachment.php?attachmentid=105043&d=1400208246

Assembly Order:
http://castboolits.gunloads.com/attachment.php?attachmentid=105042&d=1400208246