Stirring the pot... Best technique for making a custom body die?

[thefitter]

I want to revisit this question because the last time it came up it seemed "unresolved" in my mind.

What is the best technique for making a custom body die?

1) Having a custom body die reamer made by using the data from a custom chamber reamer print?

2) Having a custom body die made by using the data from a case(s) that has been fired 3 times?

Thanks

 

[taliv]

perhaps i'm missing something, but how would either of those actually size a case?

e.g. as it's fired, a case expands to fill the chamber then contracts slightly and is ejected. so the body is now already smaller than the chamber. how would sticking it back in the chamber make it even smaller?

 

[Patch700]

perhaps i'm missing something, but how would either of those actually size a case?

e.g. as it's fired, a case expands to fill the chamber then contracts slightly and is ejected. so the body is now already smaller than the chamber. how would sticking it back in the chamber make it even smaller?

I would venture to guess that what he means is if you have a chambering reamer with a specific set of dimensions you could take those dimensions and have a sizing reamer made minus the clearance you desired.. So if his chamber reamer was .4690" at the base with X amount if taper and .4530" at the body shoulder junction , he could get a reamer cut at .4680 base and .4520 at the body shoulder junction.

Personally if you are serious about getting a properly fitted sizing die I would opt for having one made from fireformed brass in the event there was a slight difference between the prints and the finished product.

 

[mikecr]

I send fire formed brass off to JLC Precision, and I assume(because I don't know for sure) he hones a smaller die to minus 1.5-2thou of my brass measure.
I say this because for my body dies I send him brass that's oversized, from over pressure loads, and with this I get back bump dies that do not size bodies. perfect.

I could have die blanks cut with a sizing reamer of my desire, when i get barrels finished.
I've had Wilson seating die blanks finished with my chamber reamer, but haven't messed with any Wilson neck dies.. They're fine the way they come.

 

[Dusty Stevens]

I heard JLC has quit. Send em to whidden if thats the case. He does a very good job

 

[Greyfox]

I heard JLC has quit. Send em to whidden if thats the case. He does a very good job

I suppose it's possible that Jim has quit fitting dies, but I sent him a Forster 222 Mag die 3-4 months ago to work with a 6x47 case. He honed the die to fit the fired case and sent it back to me. It works very well. It's my understanding that in a situation like mine, the factory dies typically oversize the case. Jim hones the die to fit the chamber based on the fired case.

Rick

 

[Dusty Stevens]

He is good thats for sure. I have a few of his dies. I know i heard from a reseller when i tried to order one that he at least quit making the micrometer wilson type seater.

 

[Rtheurer]

I don't really understand why a guy would want to go through all this time and expense for a sizing die. What if you just made your finish Chamber reamer to match the already existing FL die so you don't have to buy expensive dies and another reamer? Same exact outcome without all the drama?
If its a wild cat that is not made by the die manufacture of your choice.... I get that.

 

[thefitter]

I don't really understand why a guy would want to go through all this time and expense for a sizing die. What if you just made your finish Chamber reamer to match the already existing FL die so you don't have to buy expensive dies and another reamer? Same exact outcome without all the drama?
If its a wild cat that is not made by the die manufacture of your choice.... I get that.

So you are saying have your chamber designed and reamed around a stock factory sizing die specs?

Thanks

 

[Rtheurer]

yes

 

[BoydAllen]

I have done that several times. It starts with some well work hardened cases that are in fired conditions and a FL die that will size them. Size some cases (no expander). Measure them carefully, and add whatever chamber clearance that you want, and order your reamer. Using the sized brass takes care of spring back. You don't have to guess. You have what the die produces. The reason for well used brass is that work hardening will result in more spring back and they will be larger than a once fired case would be. You can use a bushing die, or if you want a tight neck chamber it can be done with a one piece die. This is not a job for someone who has visualization issues, but it is really no problem if you take your time and think it through.

 

[thefitter]

What if this is a new caliber and build?

Thanks

 

[BoydAllen]

Then I would take the parent case head dimension into account, so as not to end up with a click problem at one extreme, or too loose a fit at the other, and design my reamer, chamber the barrel build the rifle, fire a couple of cases more than once working up to a suitable pressure, neck sizing only, and then send those cases to Neil Jones and have a FL die made with a couple of different size bushings. This would take longer, but it if is worth doing, it is worth doing right. This assumes that the case could be fire formed and did not require forming before firing. If your design requires that cases be formed before firing, it becomes more complicated. What are you contemplating?

 

[thefitter]

Then I would take the parent case head dimension into account, so as not to end up with a click problem at one extreme, or too loose a fit at the other, and design my reamer, chamber the barrel build the rifle, fire a couple of cases more than once working up to a suitable pressure, neck sizing only, and then send those cases to Neil Jones and have a FL die made with a couple of different size bushings. This would take longer, but it if is worth doing, it is worth doing right. This assumes that the case could be fire formed and did not require forming before firing. If your design requires that cases be formed before firing, it becomes more complicated. What are you contemplating?

I have discovered that the factory Redding body die is just not sizing the body enough. I need to know the best way to have a custom body die made. I have a custom JGS chamber reamer print for this chamber, and I could spec a new sizing reamer using the dimensions off that print, but I have read more than a few people saying that using three 3X fired cases will be more accurate to my actual chamber because of chambering variables. I guess I could compare both sets of data and then decide. If the fired cases match the print then it should be a no brainer.

I'm going to give JGS a call this AM and discuss it.

Thanks

 

[mikecr]

I would avoid any die that sizes the entire neck length(custom or not).
And I also believe use of fully fireformed brass provides for best dimension information.

It's difficult to predict chamber expansion on firing, and so difficult to know exactly what you'll produce with it. This is why it makes sense to form in your primary die(your chamber), albeit dynamic, first.

 

[william5409]

I heard JLC has quit. Send em to whidden if thats the case. He does a very good job