FL Sizer and Chamber Mismatch Question

[Ein]

Here's the setup. I'm loading for 2 squirrel rifles on a Dillon 550 with the goal of being able to produce 1/2 minute-of-squirrel ammunition in mass. Both rifles are chambered identically. Redding Full Length Sizing die is the only sizing step. Formed 20 cases to load and shoot a few times to check for gremlins in the setup. Firings 4 and 5 led to case separations.

Accordingly, the detective work began. Both rifles just BARELY close on a GO gauge. I wouldn't even call it resistance in the last tiny bit of handle travel, but you can just barely feel the gauge. I put the go gauge in the full length sizer and the head protrudes roughly 0.134". I say roughly because I used the caliper like a depth gauge from the go gauge head to the bottom of the die, not very precise. The problem is, the Dillon pushes all but 0.120" of the case into the die. Anyone have a quick solution besides backing the die out and using the linkage stop to stop the up-travel of the ram? Long term fix will be a custom die.

Thanks for your time!

 

[dkhunt14]

Even with a custom die, the die will have to set up for headspace. Which means it may have to be backed off the shell holder. You need a Hornady headspace Guage and measure a fired case and set die to bump shoulder .001 to .002. Why wouldn't you just back off the die some? It makes no difference if it contacts shellholder or not. The pressure the case puts on the die during sizing straightens everything out. MATT

 

[Ein]

Even with a custom die, the die will have to set up for headspace. SNIP Why wouldn't you just back off the die some? SNIP MATT

I ought to be able to have a custom die reamed the proper depth. I don't want to back the die off as I will need to reset all the dies in the toolhead. Currently the sizing die is the vertical stop for the ram. Long story short, I am lazy. Hence my effort to make decent ammunition fast and easy, with long, low maintenance case life.

 

[dkhunt14]

I ought to be able to have a custom die reamed the proper depth. I don't want to back the die off as I will need to reset all the dies in the toolhead. Currently the sizing die is the vertical stop for the ram. Long story short, I am lazy. Hence my effort to make decent ammunition fast and easy, with long, low maintenance case life.

Maybe you can have one made long on headspace and shorten to what you need. They won't know what headspace is in your gun and hitting it exact will be hard. Even custom dies are made with adjustment to change headspace. MATT

 

[DocDoc]

Maybe you can have one made long on headspace and shorten to what you need. They won't know what headspace is in your gun and hitting it exact will be hard. Even custom dies are made with adjustment to change headspace. MATT

I guess I do not understand how the Dillon press works. How does backing the sizing die out a few thousandths change the function of the other dies?

 

[msinc]

I ought to be able to have a custom die reamed the proper depth. I don't want to back the die off as I will need to reset all the dies in the toolhead. Currently the sizing die is the vertical stop for the ram. Long story short, I am lazy. Hence my effort to make decent ammunition fast and easy, with long, low maintenance case life.

You are an honest person, I will testify to that!!! However, if you are really this "lazy" then you should seriously consider getting out of reloading. I am not being facetious at your expense. You should either buy ammo already loaded or buy a gun that has loaded ammo available. Your effort is noted, but the words "decent, fast and easy" do not go together when it comes to reloading accurate ammo. First thing you should realize is that your pipe dream of "being able to have a die made..." to always size every case to the exact same headspace length is not going to happen. I don't know of any dies that are not "made to the right length".....You always have to set up your headspace length depending on your cases, no matter who machined the die.

 

[Ein]

I guess I do not understand how the Dillon press works. How does backing the sizing die out a few thousandths change the function of the other dies?

The Dillon has one ram with four shell holding positions. In my case, the first shell holding position sizes the case. I set up the die so the shell holder hits the bottom of the die, limiting upward travel of the ram. The other two dies (powder dispenser and seater) are adjusted to function correctly when the ram stops on the sizing die in the first position. It's not that big a deal to move them all, I was just trying to come up with a clever way to maintain the max upward travel datum, while changing the depth that brass is pressed into the sizing die.

msinc, Thanks for the concern, but I haven't shot factory ammunition in anything but rimfires for years. I understand setting dies up for headspace and how that adjustment changes over time with each firing, etc. In this particular setup, I'm alright with bumping them farther for the sake of reliability, but sizing them down over .012" is seriously detrimental to case life. I've got "decent and fast" figured out, I'm just sorting out the only gremlin between me and "easy".

On the die note, I've got to think that a custom die maker can figure out how to hit a dimension for depth within .001". My 16 year old brother can do that. I can get a fairly exact headspace dimension using my go gauge, shim stock and a micrometer. Is there some voodoo in the die making process I'm missing?

 

[Toby Bradshaw]

First of all, you can't easily assess the dimensions of your FL die with a go gauge. The die is smaller than you might think, because brass springs back after sizing, so the die has to produce a minimum-spec case after sizing. I doubt that your go gauge has much "give" or springback in it.

As others have pointed out, you need to measure how much your die is pushing the shoulder back relative to a fired case that is tight in the chamber. Get one of the tools that can measure this.

Second, you can get up to 0.010" less sizing with these, while still touching the base of the die with the shellholder:
http://www.redding-reloading.com/online-catalog/35-competition-shellholder-sets

Of course, moving the shoulder less could simultaneously produce too little sizing at the base, depending on the dimensions of your die and chamber(s).

 

[Ein]

My go gauge is over .010 smaller than sized new brass at the body-shoulder junction. Can it spring back that much? I've seen .002-.003 in pretty hard brass, but .010?

 

[BoydAllen]

Adjust the sizing die to achieve the proper amount of shoulder bump, and the others as needed. End of problem. Just now I have done a little reading on a Dillon forum and based on what I have read, you should have no problem. The amount of bump that you get from a particular die setting will vary with the hardness of the brass, which is a good argument for keeping brass in batches that are the same as far as manufacturer, and number of firings. If you use your brass for many firings, it will work harden, and that will require resetting your die to maintain shoulder bump.

 

[Toby Bradshaw]

My go gauge is over .010 smaller than sized new brass at the body-shoulder junction. Can it spring back that much? I've seen .002-.003 in pretty hard brass, but .010?

The only go gauge dimension that has a spec is the base to datum line.

And you can't really tell what part of your go gauge is hitting the inside of the die. You could make a chamber cast of the die if you really want to know its dimensions.

In short, measure your brass when 1) new, 2) after firing (perhaps multiple times with neck sizing only until the brass gets tight), 3) after sizing. That will tell you what you need to do.

Or, throw your brass away after 3 loadings, and call it good.

 

[Ein]

Toby,

This is a wildcat chamber so "specs" are relative with my reamer spec setting the standard. The go gauge determined the depth the chamber was cut to. Said go gauge is smaller, by about .015-.017 in diameter, at the body shoulder junction than fired brass. It is also smaller, by .010 in diameter, at the body shoulder junction than sized brass. I think it's safe to say that the first thing my go gauge is going to crash into in my FL sizing die is the shoulder. Given that it appears to be concentric and ground with precision, I ought to be able to use it as a gauge to carefully measure against. It is constant, without "springback" and should be a fairly exact way to compare the hard dimensions in the chamber and die with regards to length. I have measurements of brass from casehead to shoulder in all three states. The problem I was addressing was my short die and clever ways to preserve the shellholder-die contact position and simultaneously hold the brass about .012-.011 short of the die. Redding shellholders would be great, but they arent compatible with the dillon shell holding system.

I think Boyd is right...I'll go set it all up over again...

Thanks for the help guys.

 

[ireload2]

The solution is do not use the bottom of the die for a stop. You are stopping on the shell plate which is probably flexing or at least deflecting.
Then set the FL sizer to produce sized cases to fit your chamber.
Adjust the rest as necessary.
Lose the laziness or it will eventually bite you. To be a good hand loader you need to enjoy it.
If you only do it as a chore to save a few bucks you will eventually compromise quality and safety.

 

[ireload2]

Can you tell the custom die maker what dimension to set the die to? Do you know exactly what dimension your chamber is at to the nearest .001.
Do you know how much your sized cases vary over a lot of 100?

On the die note, I've got to think that a custom die maker can figure out how to hit a dimension for depth within .001". My 16 year old brother can do that. I can get a fairly exact headspace dimension using my go gauge, shim stock and a micrometer. Is there some voodoo in the die making process I'm missing?

 

[Ein]

All right guys, the lazy thing was a joke. I comprehend setting dies for desired headspace, watching that dimension change with subsequent firings etc. All this stuff is a compromise. You can reset your sizing die each firing, if its worth it to you. For this setup, I will be shooting, sizing, shooting, sizing until I get less than .002 bump, then annealing. Maybe the first firing, maybe the 5th, I'll find out. All I was looking for was a clever trick someone else had found to precisely shim the dillon shellplate up, so I could back the die out, without affecting the setup of the other dies. If I had .010 shim stock handy last night I'd have just made a shim, but I didn't. Thanks again for the input.

 

[Ein]

Can you tell the custom die maker what dimension to set the die to? Do you know exactly what dimension your chamber is at to the nearest .001.
Do you know how much your sized cases vary over a lot of 100?

Short answer, I can give them a dim that will work, if we use the same standard, i.e. my go gauge. The die maker has no idea how much variance is in a lot of 100 pieces of my particular lot of brass either. Actually, I'd probably make a die myself but I'm not familiar at all with specific alloys or heat treating used in reloading dies.

EDIT: Keep in mind guys this is all no fuss reloading for blowing squirrels up with family and friends. I'm not loading for the LR Benchrest Nationals. No neck turning, no trickling to the nearest kernel, no sorting brass by anything other than "no split necks, no huge dents..."etc. I want decent case life (10 firings) with minimal prep. I have 700 pieces of brass.

 

[chuckshooter]

I'm not trying to be mean here, but it would take you less time to back off the dies to the proper spots than it took you to post this. every custom die I have, I still have to setup for proper dimensions.

 

[hottshott526]

If you continue to use the shell plate as a stop for the die. The shell plate can and will bend if the pressure is to much. These machines are not designed for the die to bottom out/ cam over on the plate, like on a single stage press.

If the shell plate gets bent,
not only will it not rotate freely around the machine but headspace measurements will be all over the place due to it being a 4 station machine and each slot will give a different measurement.

Every 4th piece of brass will be close to the same dimensions but as mentioned earlier, brass hardness and spring back comes in to play per each piece causing a wide variety of headspace measurements.

I know this from experience and it will drive a person insane trying to figure it out. The good thing is that Dillon will replace a shellplate even though, in my case, it was operator error.

 

[Ein]

You're absolutely right. No offense taken. That's exactly what I was doing this morning while keeping tabs on this thread. Wrapped it up just before the wife woke up growling for breakfast.

Im still going to investigate the die route. I like firm stops (shell holder on die) for sizing operations. There's no way to screw it up.

Just saw hotshots reply. Thanks. Duly noted.

 

[chuckshooter]

You're absolutely right. No offense taken. That's exactly what I was doing this morning while keeping tabs on this thread. Wrapped it up just before the wife woke up growling for breakfast.

Im still going to investigate the die route. I like firm stops (shell holder on die) for sizing operations. There's no way to screw it up.

Just saw hotshots reply. Thanks. Duly noted.

Really big question is where are you shooting these massive quantities of squirrels. I go to Cedarville 4 times a year and shoot roughly four to five thousand rounds and now I'm looking for somewhere else to go as well. with the change in laws and the landowners are starting to poison I can see issues in the future