I need some help from the math wizards

Patriot

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With a standard reloading die (Dillon, RCBS, etc) I need to know the vertical distance
traveled against some unit of rotational distance. So, if I rotate the die, say one half
turn, how much vertical distance will I travel?

TIA,

TBP
 
Thanks,

So each five degrees of rotation will move the die about .001" then. What is
the rotational distance traveled in five degrees of rotation?

1 full rotation = 360 degrees
1/72 rotation = 5 degrees

I can't even begin to suggest how you measure 1/72 revolution.
 
If you are trying to figure out how much you are bumping the shoulder back when you turn the die in a certain amount, that is going to be a nightmare to deal with the lock ring. When you really tighten up on the lock ring, the die usually moves a bit.

This is what you want:
http://www.sinclairintl.com/cgi-bin/category.cgi?category=REMTHT&item=HK-66&type=store

It will give you numbers to sort out your resizing difficulties.
 
If you are trying to figure out how much you are bumping the shoulder back when you turn the die in a certain amount, that is going to be a nightmare to deal with the lock ring. When you really tighten up on the lock ring, the die usually moves a bit.

This is what you want:
http://www.sinclairintl.com/cgi-bin/category.cgi?category=REMTHT&item=HK-66&type=store

It will give you numbers to sort out your resizing difficulties.

Yeah, I know. I'm trying to sort this stuff out prior to my next contact with my favorite CSR.
 
1 full rotation = 360 degrees
1/72 rotation = 5 degrees

I can't even begin to suggest how you measure 1/72 revolution.

Measuring it is not the problem. The diameter of the die is 7/8". Therefore each
5 degrees of rotation equal slightly more than .038". Not an insignificant amount and
very measurable.
 
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You really need one of these, or another gauge like an RCBS Precision Mic to measure the cartridges headspace.

Once you get measurements, get a set of die shims or headspacing shellholders to help you fine tune.

B

I'm not sure why I need another gauge. My headspace gauge is not the problem. In fact
the headspace gauge I have is pretty good. It's telling me that whatever I am doing with
the die is not cutting it. This is a very simple problem. The sizing die/press combo doesn't
provide the necessary adjustment to be able to meet the criteria required by the case gauge
and the manufacturer of that case gauge. I think I could measure this with a scanning electron
microscope and the results would not be any different. I'm afraid I am being somewhat
dense in understanding what you are trying to tell me so I will apologize for my denseness.

When I measure the case in the sizing die with my calipers, the case protrudes about
.002" above the high step flat on the case gauge. I cannot get the press/die combo to
reduce that dimension. I have reloaded the same rounds on that press with RCBS dies
and they do not exhibit this problem. When I look at the sized cases I have from my
RCBS days they size perfectly between the high and low steps on the same case gauge.
That is all I am trying to achieve.

If I understand what you are saying I cannot see where adding height to the die with
shims, etc. would alleviate the problem. In fact from where I am sitting I would think
it would compound it. Am I wrong?

I'm open to all ideas, especially if I can solve this problem without the pain of more CSR
interaction. [smile]
 
Measuring it is not the problem. The circumference of the die is 7/8". Therefore each
5 degrees of rotation equal slightly more than .012". Not an insignificant amount and
very measureable.

um.... the circumference of a 7/8" diameter die is 7/8 * PI = 2.749" ..
each 5 degrees of rotation would equal .038" on the circumference of the die.

However, if I wanted to set a die .005" further than some point, I would tighten it down with a .005" feeler between the locknut and press. After tightening the setscrew in the nut, I would back the die out a bit, remove the shim and then turn the die in all the way.

But then, I have a thing about doing things the easy way, and 40+ years in the manufacturing trades learning how.[smile]

Jack
 
If you get the gauge and measure your brass and what you are resizing to, you might be surprised that you're resizing beyond the .003" shoulder bumper in the course of trying to get the brass in the case gage. I think that is because the case gage is much tighter than your chamber. That's what I found when I started measuring everything and following Zidiker's book.

That's not the answer to this thread's question but just what I've been thinking about after reading a few of your recent threads here and on BE.
 
um.... the circumference of a 7/8" diameter die is 7/8 * PI = 2.749" ..
each 5 degrees of rotation would equal .038" on the circumference of the die.

However, if I wanted to set a die .005" further than some point, I would tighten it down with a .005" feeler between the locknut and press. After tightening the setscrew in the nut, I would back the die out a bit, remove the shim and then turn the die in all the way.

But then, I have a thing about doing things the easy way, and 40+ years in the manufacturing trades learning how.[smile]

Jack

As the thread is titled, need help from the math wizards. [smile] Thanks Jack. I did bake
a Northern Spy apple pie today. [smile]
 
I'm not sure why I need another gauge. My headspace gauge is not the problem. In fact
the headspace gauge I have is pretty good.

I wasn't really refering to your post. Simply adding to GTO's post about having a cartridge headspace gauge to get things set up properly. Without one, you don't really know what the case is being blown out to.

....I'm open to all ideas, especially if I can solve this problem without the pain of more CSR
interaction. [smile]

It sounds like you are having a problem with sizing the case completely? If you can add some information I can try and help.

Can you tell me what:
  • Cartridge
  • Press
  • Die
  • What kind of gauge do you have?

B
 
I wasn't really refering to your post. Simply adding to GTO's post about having a cartridge headspace gauge to get things set up properly. Without one, you don't really know what the case is being blown out to.



It sounds like you are having a problem with sizing the case completely? If you can add some information I can try and help.

Can you tell me what:
  • Cartridge
  • Press
  • Die
  • What kind of gauge do you have?

B

The problem I am having is sizing the cases completely. The dies will not move the shoulder far enough.
Sounds simple, but evidently it seems to be a problem I cannot resolve just yet with my supplier.

Cases: Any of the following in .223: FC, R-P, LC, Mixed Mil, etc.
Any of the following in 30-06: R-P, LC, Mixed Mil
Press: Dillon 550B
Die: Dillon .223 Carbide Die Set, Dillon 30-06 Standard Die Set
Gauge: Dillon on both, stainless on the .223, standard on the 30-06.
 
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The problem I am having is sizing the cases completely. The dies will not move the shoulder far enough.
Sounds simple, but evidently it seems to be a problem I cannot resolve just yet with my supplier.

Cases: Any of the following in .223: FC, R-P, LC, Mixed Mil, etc.
Any of the following in 30-06: R-P, LC, Mixed Mil
Press: Dillon 550B
Die: Dillon .223 Carbide Die Set, Dillon 30-06 Standard Die Set
Gauge: Dillon on both, stainless on the .223, standard on the 30-06.

Richard,

All I need now is my shell plate for .223 and then I can attempt rifle reloading. Looking forward to your having figured it all out with the help of others snce it will save me a lot of aggravation. [grin]
 
I think you're getting a little hung up on fitting your case gage rather than measuring what you're doing to the brass. You want to bump the shoulder back .002-.003", not more than .005", from where it was blown out to when fired. How do you know your not going past that? That could cause your brass distort and not fit your style gage properly. That would give you a false sense that you aren't getting enough adjustment.

Get a micrometer-type tool, measure new, fired, and resized brass at the datum line, and make sure the resized brass is .002-.003" shorter than the fired brass. That's how it is from the Zediker book, Tubb's video, and the RCBS guy on Shooting USA. You might find that when you do it that way it with then fit in your other gage.
 
Take a fired case and measure it in the Dillon case gauge with your calipers. Record that reading.

Take a unfired case of the same type (LC or FC), or a brand new cartridge and measure it with the gauge and calipers. The difference in the reading is what your chamber is blowing the case out to. If it's an AR it's probably 5-8 thou. difference. Make sure to use the same type of case since the brass is slightly different in each brand, and sometimes they react to sizing differently.

Set your dies up according to how Dillon recommends. I don't have a Dillon, but on a single stage you screw it down until it touches the shell holder when the ram is all the way up. Probably the same on a Dillon but I'm not positive. Size a case. Make sure to use lube and make sure to lube the inside of the neck.

Now measure that sized case in the Dillon case gauge. You want to adjust the die, based on this reading. You only need it be a couple of thousandths below the fired case measurement. In a single stage press, the case will be squeezed down a lot. Probably below what a new case or cartridge measures.

This is where the shims come in. You can also unscrew the die and adjust it, but as you have figured out that is a pain. If you need to size the case less, just put a shim of the correct thickness needed to size the case less.

I know that the removable tool head has some flex in it, but the .223 should be able to be sized enough to chamber in your rifle without a problem. Not sure about the 06 though.

If this doesn't clear up your problem, please post the measurements that the fired and unfired cases measure.
 
Measuring it is not the problem. The circumference of the die is 7/8". Therefore each
5 degrees of rotation equal slightly more than .012". Not an insignificant amount and
very measureable.

I suspect it is the diameter of the die that is 7/8".

This makes the circumference about 2.75".

This in turn makes 1 degree of circumference subtend to about 0.0076"; five degrees, about 0.038" or a smidge more than 1/32".
 
I actually ran down to my bench and did an experiment. I took a piece of my gorgeous perfectly resized brass. It dropped in and out of my Wilson (same style as the Dillon) case gage like butter and was right below the headspace line as it should be. I put it in my press and resized it again but with the die down about a 3/4 to 1 turn further. It pushed the shoulder back .004" further as measure with the tool mentioned above. Sure enough, I dropped it in the Wilson case gage again and the rim was sitting above the max line. When you bump the shoulder too much, the brass you move has to go somewhere, and where it goes could make it not fit a gage like the Wilson or Dillon.

So you could be ranting about not enough adjustment in the die when you are actually over the adjustment you want to be at. It is actually understandable confusion if you don't have the means to measure the brass.

I hope that makes sense, and there are plenty of more experienced rifle reloaders than me, so correct me if I'm wrong.
 
I suspect it is the diameter of the die that is 7/8".

This makes the circumference about 2.75".

This in turn makes 1 degree of circumference subtend to about 0.0076"; five degrees, about 0.038" or a smidge more than 1/32".

Thanks RKG,

Jack pointed out my error to me already. You are correct I was referring to diameter and
as my skills slowly erode due to age, I can't even see the error in front of my eyes when
typing it. [smile]
 
I actually ran down to my bench and did an experiment. I took a piece of my gorgeous perfectly resized brass. It dropped in and out of my Wilson (same style as the Dillon) case gage like butter and was right below the headspace line as it should be. I put it in my press and resized it again but with the die down about a 3/4 to 1 turn further. It pushed the shoulder back .004" further as measure with the tool mentioned above. Sure enough, I dropped it in the Wilson case gage again and the rim was sitting above the max line. When you bump the shoulder too much, the brass you move has to go somewhere, and where it goes could make it not fit a gage like the Wilson or Dillon.

So you could be ranting about not enough adjustment in the die when you are actually over the adjustment you want to be at. It is actually understandable confusion if you don't have the means to measure the brass.

I hope that makes sense, and there are plenty of more experienced rifle reloaders than me, so correct me if I'm wrong.

Hmmmm,

I might try this out. When I started this whole process I did as the directions stated which
was to raise the shellplate and bring the die into contact with it, then back it off one half
turn ( a pretty large amount) and adjust from there. I did it incrementally but maybe I
tripped over the correct setting. I'll give it a shot. Thanks GTO.


ETA 12/18/2008: I gauged three different (new, not reloads) rounds* this morning, one .223 and
two 5.56 and they all gauged halfway between the upper and lower rails on my case gauge.

Unfortunately my reloads are still .002" above the top rail. [sad] The good news is that I haven't
tried GTO's suggestion just yet. I will try that later today. Going to the range shortly to exercise
the 11's. [smile]


*American Eagle (FC) .223, PPU 5.56mm, LC XM193 5.56mm
 
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Richard,
If you need to borrow the gauge to measure shoulder bump. I will drop mine off for you to use.

I take a fired brass, measure the shoulder, resize it. measure the shoulder again, I adjust the die if needed. Simple and quick
 
Richard,
If you need to borrow the gauge to measure shoulder bump. I will drop mine off for you to use.

I take a fired brass, measure the shoulder, resize it. measure the shoulder again, I adjust the die if needed. Simple and quick

Thanks SM,

For the time being I won't need the gauge since I am returning the sizing dies for the .223
and the .30-06 to Dillon where they will either correct them or replace them.

Thanks to all for your help, I will keep you updated on my progress.
 
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