Resizing question?

[ropeup79]

On fat cases like WSM’s I’ve had to raise the decapping rod up in the die so the expander ball doesn’t push down on the case mouth too early. If the case body isn’t supported enough when the expander ball starts pushing down it can cause a very slight bulge at the body/shoulder junction. This bulge is hard to see and usually needs to be fully resized to remove.

 

[MichaelC]

Most of the time when you have cartridges not fit after sizing it’s not the shoulder that is too far forward; rather it’s the base of the case at what is known as the .200 line. Basically the ass is too fat. You may need a small base sizing die, or a die that has a smaller base. Not all sizing dies are the same for a given cartridge. Redding are large on the ass end, RCBS are usually small. Forester are in the middle. Huge generalization but at least in 308 it is true. Using a sharpie on the back and on the shoulders you will probably find that it’s not the shoulder that is impeding the chambering. And, it’s not because you need to anneal.

 

[TaperPin]

Thank you for your explanation, I'm guessing it's either user error on the press or a bad die. I have a factory Tikka 300 WSM barrel that I installed myself and that might marginally affect headspacing, but shouldn't affect the shoulder geometry. The chamber is a little tight on factory Federal ammo with 0.001 or less clearance (scotch tape test) before firing.

Even if I don't get over-worked brass, I'm still unsatisfied with having to bump 0.010" to make chamber-able brass and re-fire-forming my shoulder each time; that somewhat defeats the purpose of reloading.

You know that reference diameter of .541” to .543” that’s shown 1.500” up from the base - out of curiosity I measured some 1/4” drive sockets that were handy and an old 3/8” craftsmen deep socket measured .544” and the regular socket was .543”. You might find something close like that and use it to gently test the diameter inside the die to see if it’s oversize.

 

[Andouille]

Most of the time when you have cartridges not fit after sizing it’s not the shoulder that is too far forward; rather it’s the base of the case at what is known as the .200 line. Basically the ass is too fat. You may need a small base sizing die, or a die that has a smaller base. Not all sizing dies are the same for a given cartridge. Redding are large on the ass end, RCBS are usually small. Forester are in the middle. Huge generalization but at least in 308 it is true. Using a sharpie on the back and on the shoulders you will probably find that it’s not the shoulder that is impeding the chambering. And, it’s not because you need to anneal.

Good points to consider. I'm fairly certain that the shoulder is the issue because of the visible bulge, sharpie test in LE Wilson case gauge showing odd mid-shoulder contact, and because a 0.010" (excessive) bumped case fits normally in the gauge and chambers smoothly in the gun. Also, I can slide a sized case backwards 1/3" farther into the case gauge than a fired case, indicating that the fired case has a larger diameter near the case head; an analog to the clever socket test @TaperPin mentioned above.

 

[MichaelC]

Good points to consider. I'm fairly certain that the shoulder is the issue because of the visible bulge, sharpie test in LE Wilson case gauge showing odd mid-shoulder contact, and because a 0.010" (excessive) bumped case fits normally in the gauge and chambers smoothly in the gun. Also, I can slide a sized case backwards 1/3" farther into the case gauge than a fired case, indicating that the fired case has a larger diameter near the case head; an analog to the clever socket test @TaperPin mentioned above.

I may be misunderstanding you but are you tying to see if your sizing your brass enough by using a case gauge and not the chamber that it was fired out of?

 

[Andouille]

I may be misunderstanding you but are you tying to see if your sizing your brass enough by using a case gauge and not the chamber that it was fired out of?

In this instance, the case gauge just provides me comparative data between new, fired, and fired-then-resized cases regarding shoulder shape (sharpie test) and case width at the base (inserted cartridge backwards). All are relative data points to help understand the excessive bump required for chambering in my Tikka.

I determined the shoulder bump required for fired brass in my rifle with the bolt ejector removed, then using scotch tape and a caliper with comparator to measure maximum chamber-able length, then subtracting 0.002. Once fired brass that is resized must be <1.768 to chamber whereas fired brass up to 1.773 will chamber. The fact that I can re-chamber some (not all) 2x fired brass suggests to me that it's a die resizing rather than chamber issue.

A lot of great discussion and suggestions here. I'll post an update when I've tried a different FL sizing die.

 

[MichaelC]

What dies are you using just out of curiosity? And, I have seen bushing dies cause some weird issues. Forester are my favorite. And, I have started only getting the FL dies from them that they will custom hone to my dimensions per the Forester instructions on their website.

 

[Andouille]

Hornady Custom Grade, so not a bushing die. But I keep hearing great things about Forester dies...
That has me wondering if my Hornady die is sizing the neck to small, requiring excessive force to run the press and damaging the shoulder.
Fired brass = 0.343-0.346
Sized brass = 0.328-0.330
Sized & mandrel-expanded neck = 0.039
Loaded brass = 0.338-0.339
So the die is sizing the neck down 0.013-0.018"... and my neck tension seems very low at 0.001-0.002.

 

[Andouille]

Follow-up: neck-sizing with a Lee Collet die allows fired brass to chamber and shoot, and I also tested a Lee FL die which bumped back the shoulder 0.002-0.003 without damaging the shoulder, but sized the neck a little smaller than I'd like. So my issue is definitely with the setup or use of the Hornady dies. I have a LE Wilson bushing die and bushings on the way that should resolve the issue. This has been an interesting and expensive learning experience.

Interestingly, the Lee Collet die bumps back the shoulder on annealed Norma brass by 0.003-ish. I wonder if it's just the softer nature of the Norma brass that makes it susceptible to shoulder bump/shaping when annealed. I'll be extra cognizant of this potential issue.

 

[sveltri]

Follow-up: neck-sizing with a Lee Collet die allows fired brass to chamber and shoot, and I also tested a Lee FL die which bumped back the shoulder 0.002-0.003 without damaging the shoulder, but sized the neck a little smaller than I'd like. So my issue is definitely with the setup or use of the Hornady dies. I have a LE Wilson bushing die and bushings on the way that should resolve the issue. This has been an interesting and expensive learning experience.

Interestingly, the Lee Collet die bumps back the shoulder on annealed Norma brass by 0.003-ish. I wonder if it's just the softer nature of the Norma brass that makes it susceptible to shoulder bump/shaping when annealed. I'll be extra cognizant of this potential issue.

I'd be concerned if my collet die was bumping the shoulder. I use one on my 243 AI (standard 243 Lee Collet die) and it does not bump the shoulder. Peterson once fired and annealed brass.

 

[MichaelC]

Follow-up: neck-sizing with a Lee Collet die allows fired brass to chamber and shoot, and I also tested a Lee FL die which bumped back the shoulder 0.002-0.003 without damaging the shoulder, but sized the neck a little smaller than I'd like. So my issue is definitely with the setup or use of the Hornady dies. I have a LE Wilson bushing die and bushings on the way that should resolve the issue. This has been an interesting and expensive learning experience.

Interestingly, the Lee Collet die bumps back the shoulder on annealed Norma brass by 0.003-ish. I wonder if it's just the softer nature of the Norma brass that makes it susceptible to shoulder bump/shaping when annealed. I'll be extra cognizant of this potential issue.

Collet dies don’t bump the shoulder at all. You are most likely crushing the case slightly and pushing the brass back. I use those dies along with Redding body dies to good effect. Setting up that die is different than regular dies and you should avoid the cam over feeling. There are some discussions on accurate shooter about the proper set up.

 

[sveltri]

Ok my turn on resizing. 6.5 PRC, Lapua brass 1x fired, Hornady Match Grade die. Once fired re-chambers easily but neck ID is too large and bullet falls in. Set-up my die to only size the neck and measured shoulder bump at 0.000. Sized brass will re-chamber but requires effort and case head has a shiny spot. I am going to examine the depth the expander is set at and see if I can move it out into a position that will allow more of the case to be supported when the expander ball enters. Other than that I don't know what else to look at. Rifle is a Seekins PH2.

 

[Andouille]

I'd be concerned if my collet die was bumping the shoulder. I use one on my 243 AI (standard 243 Lee Collet die) and it does not bump the shoulder. Peterson once fired and annealed brass.

Collet dies don’t bump the shoulder at all.

Well not by design, but rather by setting up incorrectly which I now deduce is my issue. I may need to verify my die setting and if I can't adjust to reduce pressure on the case, then I'll place a thin washer around my case so that the shell holder effectively engages the collet die earlier. Or I could use a thicker shell holder from Redding.

I found some very useful discussion of the dies on Accurate Shooter as you suggested. https://forum.accurateshooter.com/t...r-affecting-shoulder-dimension.3833335/page-2
I'm extremely impressed with the consistency of neck tension resulting from the Lee Collet die based on my measurements with a cheap neck gauge pin.

 

[Andouille]

Ok my turn on resizing. 6.5 PRC, Lapua brass 1x fired, Hornady Match Grade die. Once fired re-chambers easily but neck ID is too large and bullet falls in. Set-up my die to only size the neck and measured shoulder bump at 0.000. Sized brass will re-chamber but requires effort and case head has a shiny spot. I am going to examine the depth the expander is set at and see if I can move it out into a position that will allow more of the case to be supported when the expander ball enters. Other than that I don't know what else to look at. Rifle is a Seekins PH2.

Interesting issue, I have a few questions: what ID are the necks sized to without the expander and what's the diameter of the expander ball? The ball should be about 2-3 thou above projectile diameter.

 

[sveltri]

Interesting issue, I have a few questions: what ID are the necks sized to without the expander and what's the diameter of the expander ball? The ball should be about 2-3 thou above projectile diameter.

No clue, I'll have to measure it tonight.

 

[Andouille]

Well, I'm still stumped on my WSM shoulder "rounding" issue that is preventing cases from chambering after full length sizing less than 0.006". I've now tried Hornady Custom Grade, Lee, and LE Wilson full length dies and all get the same result of rounds not chambering until I bump at least 0.006-0.007" which is excessive working of the brass. Plus I'm essentially fire-forming the shoulder each time I shoot the brass. Next step is to try ADG brass instead of the Norma I have been using. ADG is a little thicker and that might prevent shoulder rounding when FL resized. I'll start a new thread so that my issue is easier to discuss and for others to find.

 

[MichaelC]

Thank you for your explanation, I'm guessing it's either user error on the press or a bad die. I have a factory Tikka 300 WSM barrel that I installed myself and that might marginally affect headspacing, but shouldn't affect the shoulder geometry. The chamber is a little tight on factory Federal ammo with 0.001 or less clearance (scotch tape test) before firing.

Even if I don't get over-worked brass, I'm still unsatisfied with having to bump 0.010" to make chamber-able brass and re-fire-forming my shoulder each time; that somewhat defeats the purpose of reloading.

just wondering if you checked headspace with a gauge when you swapped barrels?

 

[Andouille]

just wondering if you checked headspace with a gauge when you swapped barrels?

I did not check headspace with a gauge, but I did the "scotch tape" test with a factory round and determined I had about 0.002" clearance if I recall correctly. Seemed like a slightly tight chamber as I'd expect more clearance with factory ammo. I'm trying to wrap my head around the concept of competition shellholders; whether a thicker or thinner shell holder would resize the case without deforming the shoulder.

 

[MichaelC]

Might be worth it buying or renting the gauges.

 

[Harvey_NW]

Ok my turn on resizing. 6.5 PRC, Lapua brass 1x fired, Hornady Match Grade die. Once fired re-chambers easily but neck ID is too large and bullet falls in. Set-up my die to only size the neck and measured shoulder bump at 0.000. Sized brass will re-chamber but requires effort and case head has a shiny spot. I am going to examine the depth the expander is set at and see if I can move it out into a position that will allow more of the case to be supported when the expander ball enters. Other than that I don't know what else to look at. Rifle is a Seekins PH2.

Expander ball may be pulling the neck/shoulder junction out slightly so based on your measurement it shows no change at the datum, but actually the case grew a little bit. I use FL dies and set them up for .002" bump result with expander ball in, and have never had an issue. On a non belted case anyway..

I did not check headspace with a gauge, but I did the "scotch tape" test with a factory round and determined I had about 0.002" clearance if I recall correctly. Seemed like a slightly tight chamber as I'd expect more clearance with factory ammo. I'm trying to wrap my head around the concept of competition shellholders; whether a thicker or thinner shell holder would resize the case without deforming the shoulder.

Food for thought, it's very hard to determine actual measurements without the proper tools. A comparator body with bullet inserts will get close, but they are for comparative measurements, not exact. The aluminum Hornady ones are worse and have a slight chamfer on the ID, which throws the measurement off. So measuring a factory round at the datum line and adding a piece of scotch tape won't give you an accurate enough measurement to tell you if the chamber is in spec or not. You need to use a gauge to be sure.

The only thing I can think of with the shoulder issue is that if it is in fact changing the shape, that is changing the contact point of the bullet insert, and therefore the perceived measurement. You may not be actually bumping the shoulders back .007". I'm perplexed as to why the shoulders are changing shape though, might be worth having a gunsmith gauge and scope it.