Setting Up a FL Sizing die...?

[Saluki91]

I have hit a wall with setting up my .308 Forster FL sizing die. Hopefully someone can steer me down the right path. My process is outlined below:

1 - Using my Hornady headspace comparator (anvil #4 for .308), I measured a piece of fired brass (spent primer removed). This provided a measurement of 1.165".
2 - I want to size my brass to 1.163"... size back 2 thou.
3 - I screw my Forster FL sizing die down to the shell pate, then back off a smidge (less than1/8th of a turn).
4 - I lube and size another piece of fired brass, remove the case lube, and measure to compare... no change.
5 - Repeat with the die screwed down slightly - no change.
6 - Continue to repeat step 4 with incremental moves towards the shell plate - no changes.
7 - Repeat with the die screwed all the way down, and a bit of cam-over... no change.

I thought I understood this process, but I clearly missed something (or some things).

Any suggestions?

Thanks!

 

[edwardware]

The case didn't grow longer than the die upon first firing. This indicates a reasonable snug chamber, and a not-too-short die.

Neck size only and refire that one piece of brass until it grows out, then measure it. . . but it's likely you're better off just gently camming over and working on something else in you spare time.

 

[Col. Harrumph]

I think you are measuring the total length of the case? That is, mouth/rim to headstamp? The FL die isn't going to shorten a bottleneck case (though it may lengthen it as you withdraw the neck expander). What you are doing by screwing the die down more and more, is you are bumping the shoulder back, so shortening the fat part of the case body. Or I am just completely misunderstanding your post.

 

[Saluki91]

I think you are measuring the total length of the case? That is, mouth/rim to headstamp? The FL die isn't going to shorten a bottleneck case (though it may lengthen it as you withdraw the neck expander). What you are doing by screwing the die down more and more, is you are bumping the shoulder back, so shortening the fat part of the case body. Or I am just completely misunderstanding your post.

I'm measuring from the shoulder... using a comparator.

 

[Col. Harrumph]

Ah, I missed that, sorry. Spitballing, now. Are you sure the die is touching the shoulder? Maybe the die's cavity is longer than your rifle's chamber?

 

[AJC1]

I'm measuring from the shoulder... using a comparator.

View attachment 1197778

You are using the .400 bushing right. You can do a test and see if your case is still to short for sizing. Put a primer sticking out of the base of the case and put it in your rifle and close the bolt. That will give you headspace. If the primer is fully seated then we can move to step 2.

 

[jmorris]

Any suggestions?

Can you try something like this?

Setting size die for bolt action rifle.

www.youtube.com

 

[Saluki91]

Can you try something like this?

Setting size die for bolt action rifle.

www.youtube.com

Thanks... I'll toy around with this over the weekend.

 

[Walkalong]

Occasionally, you get an out of spec shell holder or plate, or die. Not common, but it happens. I had a .223 sizer that

I had to remove a tiny bit from the bottom to get it to size cases to fit a Wilson headspace case gauge. Be very sure

that's the issue before you do.

 

[jmorris]

I had to remove a tiny bit from the bottom to get it to size cases to fit a Wilson headspace case gauge. Be very sure

that's the issue before you do.

A little trick some use to quantify how much to remove, if the shell holder is contacting the die and the case cannot be sized sufficiently, is to raise the case bottom off the of the shell holder with a feeler gauge.

Lets you know how it would work if you removed that amount from the bottom of the size die. .0015" in this example.

 

[Anchorite]

Occasionally, you get an out of spec shell holder or plate, or die. Not common, but it happens. I had a .223 sizer that

I had to remove a tiny bit from the bottom to get it to size cases to fit a Wilson headspace case gauge. Be very sure

that's the issue before you do.

Well said. I had a shell holder once that was out of spec and had to grind it down a smidge. It was forever married to that set of dies after that. Exactly why everyone who reloads should invest in a case guage.

 

[jmorris]

Well said. I had a shell holder once that was out of spec and had to grind it down a smidge. It was forever married to that set of dies after that.

Just one reason I prefer to remove material of the bottom of the die, to avoid that problem. The other being, I don't weaken the shell holder, to yank the case back out. That said, I only had one break before I realized it made more sense to remove it from the die, even if its for a single stage.

 

[Blue68f100]

A little trick some use to quantify how much to remove, if the shell holder is contacting the die and the case cannot be sized sufficiently, is to raise the case off the bottom of the shell holder with a feeler gauge.

Lets you know how it would work if you removed that amount from the bottom of the size die.

View attachment 1197834

I've done that for years when I have problems.

One thing he may need to do is check the deck height of the shell holder. This should be 0.125". These shell holders are hard and do take some time to remove the metal, besides keeping them flat. Removing metal will weaken the shell holder, but should not be enough for a failure down the line. Much easier to chuck the die up to a lathe and do a skim cut. Before I remove any material I would contact the mfg with the problem, one you determine how far the die/shell holder is off.

 

[N555]

Just one reason I prefer to remove material of the bottom of the die, to avoid that problem. The other being, I don't weaken the shell holder, to yank the case back out. That said, I only had one break before I realized it made more sense to remove it from the die, even if its for a single stage.

That's how I did it.

 

[N555]

Sounds like it's time to screw the die in till it kisses the shell holder and run it.

 

[JFrank]

I have hit a wall with setting up my .308 Forster FL sizing die. Hopefully someone can steer me down the right path. My process is outlined below:

1 - Using my Hornady headspace comparator (anvil #4 for .308), I measured a piece of fired brass (spent primer removed). This provided a measurement of 1.165".
2 - I want to size my brass to 1.163"... size back 2 thou.
3 - I screw my Forster FL sizing die down to the shell pate, then back off a smidge (less than1/8th of a turn).
4 - I lube and size another piece of fired brass, remove the case lube, and measure to compare... no change.
5 - Repeat with the die screwed down slightly - no change.
6 - Continue to repeat step 4 with incremental moves towards the shell plate - no changes.
7 - Repeat with the die screwed all the way down, and a bit of cam-over... no change.

I thought I understood this process, but I clearly missed something (or some things).

Any suggestions?

Thanks!

After sizing at # 7, does the case chamber freely?
If so then your cases are not fully fire formed yet, this is not a problem and no need to adjust the die any further ( yet )
If the case will not chamber after sizing you have an issue but until then you do not.

 

[Chuck R.]

How many firings on that brass in that chamber?

I often find it takes 3 to 4 firings before my brass is fully formed. So the first few loadings aren't bumping anything.

Once I start getting some resistance when clambering, I go through the process of setting up my dies to bump.

 

[AJC1]

We're on step 15 and I haven't seen the "problem" verified yet.

 

[Saluki91]

After sizing at # 7, does the case chamber freely?
If so then your cases are not fully fire formed yet, this is not a problem and no need to adjust the die any further ( yet )
If the case will not chamber after sizing you have an issue but until then you do not.

Cases chamber without a struggle… sounds like I’m not yet ready to worry.

Thanks!

 

[thump_rrr]

Occasionally, you get an out of spec shell holder or plate, or die. Not common, but it happens. I had a .223 sizer that

I had to remove a tiny bit from the bottom to get it to size cases to fit a Wilson headspace case gauge. Be very sure

that's the issue before you do.

My Lee 5.7x 28 FL die needed 0.002” off the bottom to size properly.

I have a perfectly flat coarse/fine whetstone that I lubricated and drew the die across in a circular pattern, with the expander removed of course.

 

[JFrank]

Cases chamber without a struggle… sounds like I’m not yet ready to worry.

Thanks!

That is correct.
Carry on and report back when you start feeling resistance .

 

[Anchorite]

Just one reason I prefer to remove material of the bottom of the die, to avoid that problem. The other being, I don't weaken the shell holder, to yank the case back out. That said, I only had one break before I realized it made more sense to remove it from the die, even if its for a single stage.

I don’t disagree with you, but in my particular situation the die (.223) did not size the shoulder back far enough (by .005”). The case gauge showed this on the first piece of new sized brass.
Needless to say, I have never purchased dies from that manufacturer again, and sold them with the rifle.