Sorry..I have a 17 fireball brass forming question

[20 TAC]

I make mine in two passes. First through 20 vartarg FL die, then pass through 17 Mach IV die. And done. Had better luck with the Mach IV die not buckling the body/shoulder junction due to its .360" measurement compared to the 17 Fireball's .366" so the die supported the case better. Never had the issues you're mentioning. Might try that method if those dies are available to you.

 

[bobcat93]

Well I figured out what is going on..
When I reform the case brass is building up at the neck - shoulder juncture. After the first form step
Die #2 necks the case to 17 cal. When is hits the build up of brass at the new neck- shoulder juncture it cause the case to buckeled.
If I turn necks first and run the cutter down onto the shoulder a little there is no build up and I can size cases correctly..

Now some one posted 17 fireball brass necks were .014- .013 thick. So that is what I'm turning necks to.
Before my reformed cases were coming out @.015
In the pic I'm pointing to the problem area

 

[bobcat93]

In this pic the area has been turned and the brass build up doesn't exist , so the case can be sized with out buckeling...it seems to have corrected the issue. Can anyone forsee a problem with this method.. Other then more work..with the form dies I have the brass needs to be necked turned anyway because it is so thick.
Is it better to turn necks or have thick necks? I think annealing is next after all this but I should have some great brass..
I wish lapua made 17 fireball brass..the only thing I can find for sale online is 17 fireball brass formed from 5.56 cases, and I don't want that.

 

[bobcat93]

After forming you should trim to length and that will solve your problem. Another thing that I do is to turn the necks before necking down as this will allow the end of cut to be on the shoulder rather than on the neck.

+1

You were 100% correct..this solved the problem!!
I just had to figure it out .

 

[bobcat93]

To follow up on this thread, I have since fired and sized the formed 17 fireball brass. My first batch was good, the second batch was bad..as I sized the brass I was ripping the case necks off coming out of the press..
Any tips on how to remove the build up of brass with out cutting deep and weakening the neck, shoulder juncture?.. Maybe I need a different cutter for my neck Turner..I tried a 40° cutter and it cuts into the neck shoulder juncture to deep..with a standard cutter it cuts into the shoulder when I try to get down to the neck / shoulder juncture..

What a pain

 

[varmintshooter]

Some of my 20 vt brass showed the same problem. I used a dry lube on the inside of the necks and the problem went away. Hope this helps.

 

[dedogs]

bobcat, What tool are you using to turn your necks? Also I may have missed it, but what rifle are you producing this brass for? Custom or factory? dedogs

 

[trapperdan]

Bobcat! -I have been following your post all along. Sorry you are still having problems. Along with the good advice other posters have given I thought I might throw in my two cents worth. Lapua brass seems to be a little thicker and harder than Remington brass therefore making it more difficult to neck down to 17 caliber. When redding designed their form and trim dies, I believe they were made for use with Remington brass. since Lapua brass is thicker, you need to neck it down in four or five steps, or turn the neck down beforehand to .012 or .013 as others have suggested. When you get a lop sided neck ,as shown, it’s usually from trying to pull the expander back out after it has been sized. With a thick neck, the hole is just too small and stretches the brass on it‘s way out. I would like to know what your outside neck dimensions are each step along the way.

 

[f18hornet]

I've never necked down to 17 caliber, but when necking down other calibers I had the best success by lowering the die a little at a time - sizing about 1/16 or so with each press until I reached the full amount. Otherwise I got crushed cases. I rotated the cases a little in the shellholder between each stroke. Used a small amount of Imperial Sizing wax on the necks. Then screwed the die out and started again. Takes more time but worked.

If a person knows how to properly do it and has the equipment, annealing the newly formed necks might not be a bad idea.

I recently saw a 22 Cheetah cartridge. It's formed from small primer .308 brass. The person who formed the cases is a machinist and had at least five or six dies that necked down small increments at a time.

 

[PigButtons]

I've never necked down to 17 caliber, but when necking down other calibers I had the best success by lowering the die a little at a time - sizing about 1/16 or so with each press until I reached the full amount. Otherwise I got crushed cases. I rotated the cases a little in the shellholder between each stroke. Used a small amount of Imperial Sizing wax on the necks. Then screwed the die out and started again. Takes more time but worked.

If a person knows how to properly do it and has the equipment, annealing the newly formed necks might not be a bad idea.

I recently saw a 22 Cheetah cartridge. It's formed from small primer .308 brass. The person who formed the cases is a machinist and had at least five or six dies that necked down small increments at a time.

Before I would try and size anything that small I would have to anneal the unsized cases to make sure they were malleable enough to withstand the "compression" of the material. I don't think the manufacturers are expecting the "new" cases to be subjected to that particular kind of stress.

I also like the idea in the above quote of using progessively deeper strokes and rotating the case with each stroke as a way to manage stresses.

And as an experiment, could you remove the expander from the dies one time and see just what the compression alone is doing to the brass?

One last thing, if you have a FL 221 Fireball die, run it over the brass to see if there is some tolerance issue in the factory brass.

 

[Powder monkey]

22 to 17 neck forming die

http://www.bullberry.com/reloading_supplies.html

 

[johnmyers]

You have a pm

 

[bobcat93]

I though this thread was dead..lots of good info here..
I have turned necks on one batch of brass and it worked great. On another batch I must have cut down to deep, because after I fired the cases I was resizing them and it ripped the necks off the cases..

As for annealing.. It can only be done after all forming is done or the cases crush in the die.

My new idea is to turn in the dies a little at a time to form

 

[bowfisher]

FWIW, I don't go from 224 to 204 in one pass. I make 2 or 3, with a bushing die, using progressively smaller bushings, AND make sure you have the height adjusted correctly, do just the neck and don't push the neck down into the shoulder with each pass.

Don't have the die set that you are using, but I wouldn't use the expander rod, if one is present. The problem is most likely too much material in the N/S junction and then if you are using the expander ball, it is pulling the neck back out unevenly....

Hope you get it all rectified. I have plenty of RP 17FB brass, but will have to make some for my 17/23 SMc in the future.