20 practical questions

[Majday]

The die

 

[L.Sherm]

Die looks like its suppose to be a FL die, I would call Redding and return it obviously its not sizing correctly by your measurements.
I use the same exact die and get alot more sizing on my brass than you are.
Have you compared the Bump on a fired case vrs sized case with the type s die?

 

[B23]

I haven't intently read through all of this but has it been established if the OP is measuring bump with a caliper and shoulder bump gauges?

Also, how far do you have your sizing die screwed down, is it contacting the shellholder to the point you're getting a small amount of cam over on your press? I ask because generally a sizing die needs to be screwed down far enough to make contact with the shellholder giving a slight cam over on the press before the die pushes the shoulder back or you can very likely end up with brass coming out of the sizing die longer, from base to shoulder datum line, than before it was sized.

 

[L.Sherm]

I ask because generally a sizing die needs to be screwed down far enough to make contact with the shellholder

I've got dies if I set them up that way ill get .010 or more bump. Every die I have and maker is different I have found.
Alot depends on if the headspace is tight or not on the chambering.
I believe there's. 005 between a go and no go guage.

 

[B23]

I've got dies if I set them up that way ill get .010 or more bump. Every die I have and maker is different I have found.
Alot depends on if the headspace is tight or not on the chambering.
I believe there's. 005 between a go and no go guage.

All the more reason to have and use shoulder bump gauge/s.

Nearly all of my dies are Redding, I think I have a couple sets of Forster and maybe way in the back a set of RCBS dies and I can't think of a single one of my Redding sizing dies that doesn't require some amount of cam over before it will push the shoulder back and if I don't the base to shoulder datum line measurement will come out longer than before it was FL sized.

 

[L.Sherm]

I agree comparator is the only true way to know.

 

[Coyotefurharvester]

Redding FL dies, raise ram/shell holder to top of stroke. Screw die in to touch shell holder. Lower ram, back die out 1/2 turn. Lube and size case(I do this adjustment without the expander). Check fit in rifle. Bolt will not close or hard to close. Screw die in 1/8 turn, size again. Check fit. Continue until case fits properly, from slight crush closing to bolt closes with no extra effort. For hunting I want no more than slight finger pressure to close bolt. Lock the die where the fit is correct, changing brands of brass may require additional adjustment. Usually I find somewhere between 1/2 turn off shell holder and slight cam over(die adjustment just past touching shell holder will properly size a case when using Redding standard shell holder. Mixing brands of shell holders and dies may complicate adjustment.

 

[Majday]

Die looks like its suppose to be a FL die, I would call Redding and return it obviously its not sizing correctly by your measurements.
I use the same exact die and get alot more sizing on my brass than you are.
Have you compared the Bump on a fired case vrs sized case with the type s die?

I haven’t compared. I will try to this evening. I don’t have a go gauge or anything to correctly measure shoulder bump. my measurements are by a non digital caliber to the thousandth.
As far as using the die, I touch the bottom of die to shell holder, lower ram and usually turn about 1/4 down so there is slight overcam. In forming/sizing I’ve gone from slight overcam to heavy. The heavier the better the chambering if the case is problematic. Using rcbs 223 fl without guts (slight to heavy overcam) has helped but still a case here and there that don’t want to cooperate.

 

[L.Sherm]

You dont need a go gauge buy a comparator like this one from Whidden .330 is the size for 20VT probably same size for 223 case whiddens has a chart.
The edge of the round hole measures on the datum line of the shoulder.

 

[L.Sherm]

As stated in a previous post always measure without a spent primer in your fired cases you can get false readings from a primer especially from the ridge on a primer from a non bushed 700 bolt.
I use decapping dies to knock out all my spent primers on my brass so its no problem checking any case I want.

 

[Majday]

As stated in a previous post always measure without a spent primer in your fired cases you can get false readings from a primer especially from the ridge on a primer from a non bushed 700 bolt.
I use decapping dies to knock out all my spent primers on my brass so its no problem checking any case I want.

Thank you for that info. I’ll look into that. It’s nice to see the exact part your talking about. I just received my small base die so I’ll see if that makes any difference in the forming/chambering process.