Headspace gauge not working? Something funky happening!

Freediver111

Sergeant of the Hide
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Feb 28, 2018
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Alright, at some point you guys might get sick of my questions about reloading but I keep banging my head on this one!

So I bought some tools to get more precise reloading. This included a Redding Type S die and Hornady comparator, plus headspace gauge bushing. I bought the C or .375 bushing for my 6.5 CM. I read that the D/.400 and the C/.375 works.

I also got a set of Redding #1 competition shellholders. I’m basically going off the sticky on this forum that outlines the process of precision reloading.

I put my bushing in the die, screw it down until it hits the shellholder starting with the .010 shellholder.

I check my shot brass and get an average neck reading of 1.559”. So I run my brass through the die and it comes back with the same reading. Then I run through ALL the shellholders in succession until I’m down to my .002 holder. The best I can get my neck reading down is 1.558”. That’s not .002 off from my fires cases so now what?

I screwed the die in about 1/4 turn and it hasn’t changed.

Wrong gauge? Screw the die down more?

I’m screwing something up, but not sure what!!!!

This is driving me nuts.

Thanks!
 

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Are you only neck sizing the brass? If so you won't be moving the shoulder your trying to measure....I suggest you full length resize until you gain more experience.
 
This is full length sizing. Lapua brass.
Not neck sizing.
I’m wondering what the heck is going on honestly. I bumped the die down another 1/4 turn and still getting similar readings. I know it’s doing so thing though because the necks are getting longer and stretched. Just having issues getting proper readings with the gauge.

And yes, I’m measuring with primers out so not getting some weird readings due to primers.
 
Why don't you just keep turning the die down until it either DOES bump the shoulder, or it hits the shellholder?

If it hits the holder, and still won't move the shoulder--and the rifle csn be VERIFIED to be in spec--then the die needs to go back home.
 
Op, you keep saying neck, when you’re talking about the shoulder, makes things confusing.


First things first. You bumped the shoulder .001, yes? 1.559 down to 1.558? You’re done! Nothing else needed. .002 is a general guideline. It could be .00075, or .0011576...doesn’t matter. .001-.002 is a good area to be in.


Now, if you must have more, put the standard shell holder back in, which would theoretically give you another .002 worth of bump. So you’d end up with 1.556. In practice, you’ll probably end up with 1.5565 or so. Do make sure that 1.559 is correct, and that represents a piece of brass that has full grown to your chamber. It is possible that your chamber is actually longer, but a softish load doesn’t push the shoulder all the way out.


Understand, you’re working with multiple sets of tolerances here. A longer chamber(producing longer fired cases), would have you working with the longer shellholders, and vice versa for shorter chambers(what you’re expereincing now). since you have a savage, you could actually adjust this(don’t do that). You’re on the good end of things now.



Load em’ up!
 
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I realize I’m measuring at the shiukder. Sorry about the confusion. But what I meant when mentioning neck was that even when I bumped the die down and still didn’t get movement on the shoulder reading, I noticed the neck get longer. So obviously I’m doing something!

I’ll set it to bump .001 and quit worrying then if that works.
 
Yes, that’s what happens. It’s mostly a product of sizing the diameters down (neck, shoulder, base). The case must move somewhere, so it gets longer.

Make sure the cases are well lubes. Also, pause at the bottom of the sizing stoke for a second or two, I bet you'll see a little more sizing out of it.
 
After touching the die with the shelholder with no load on the press turn the die in small increments further in until the press starts to "cam over".
 
The resistance of the sizing operation causes deflection in the press. This deflection with limit the amount of sizing you’ll get, because effectively the die will hover above the shellholder. You need to insure that the shellholder is touching the die completely under full load.
 
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The resistance of the sizing operation causes deflection in the press. This deflection with limit the amount of sizing you’ll get, because effectively the die will hover above the shellholder. You need to insure that the shellholders is touching the die completely under full load.

It is for sure.
Just got home so I’m going to play around with it some more.
If I can reliably get a .001” bump and that fine then I’ll just leave it at this point.
 

Alright. Got home and hit the garage.
Turned the die down another 1/4 turn or so. Re-checked the fired brass and still get 1.559”.

Now with the .002 shellholder I’m getting an average 1.5575”. Good enough!

Now the weird thing is that I ran about 20-25 through and measured each one. While many were in the 1.5575 range, I had some still at 1.558, and a few at 1.557. I’m not too worried about that variation. I did have one read 1.556, which made my head spin, but oh well I guess!

Sometimes I think reloading is bad for me. I’m way too OCD and freak the f out over little things.

One last question: how much will say a .001 variation in headspace matter when it comes to precision?
 
It’s brass, it springy, it isnt uncommon to have some variance. A slight variance in headspace won’t make a difference imo. You might consider investing in a more rigid press, which may cure some of that. Take your time and measure often. Try to be as cosistent as possible in every step.
 
It’s brass, it springy, it isnt uncommon to have some variance. A slight variance in headspace won’t make a difference imo. You might consider investing in a more rigid press, which may cure some of that. Take your time and measure often. Try to be as cosistent as possible in every step.

The more rigid press got me thinking, so I went back and tested a few new methods. When I give the press a little more oomph at the end of the stroke, I can get 1.556”, then doing it in my more normal fashion gets me 1.557 or 1.558.

I think the old hand me down Lee is a major part of the problem with inconsistencies.

Thankfully my buddy leaves his RCBS in my garage while he’s in the process of moving. I’ll test it tomorrow and if I get more consistent results, I’ll spring for a new press.
 
Problem solved! It’s my cheap Lee challenger press causing the issue. It’s sensitive to small changes in force.

I busted out my buddies old RCBS rock Chucker and set it up to cam over. Used the competition shellholders and everything g worked as it should. Consistently getting 1.5565 measurements. I realize that’s .0025” of bump instead of .002, but I should be alright with that.

Guess it’s time to upgrade presses when my buddy wants his RCBS back!
 
I just proved it works way better. I was using the .004 shellholder and got 1.5565”, tried the .006 holder and now getting 1.5575”. So my results are clear and precise, unlike when I was using the Lee.

Think I’ll stick with .0025” bump, unless .0015” is better? Maybe a little easier on brass?