Headspace question

[mausermanbob]

While we all at times overthink something, in reloading it is important to get the resizing right. Depending on the application, it may not need to be benchrest perfect, but needs to be right and under control.
You're asking the right question.

jelenko

Appreciate that.
I got a select match Shilen barrel, Zermatt receiver and decent Crimson Trace scope.
I want to squeeze every good ounce out of that system at the range, I just need to take it ready -steady-go with the reloading. Baby steps.

 

[mausermanbob]

I keep a record of the following measurements for each rifle I shoot and load for:

1. case head to datum where I can just feel contact when closing the bolt (and this is done with a stripped bolt and the primer removed from the case)

2. case head to datum that I set my sizing die for that rifle

3. case head to datum for fired brass

You can accelerate the number of firings it takes to obtain 1. by setting your sizing die high. The will move the shoulder forward and increase the case head to datum length.

If you use a good quality lube and apply it consistently, sizing 0.002" shorter than dimension 1. will work perfectly well. I set my sizing die for 0.001" less than dimension 1 and never have any issues or contact when closing the bolt. YMMV

jepp2
Thanks for that information.
I will start a log book and track exactly those things.
All the responses have moved my learning curve for the good.

 

[mausermanbob]

there is a lot to learn yes, depending on the rifle and what me or you r using it for.... getting cases for a good fit is a good practice, it's a must for accuracy again depending on the rifle and what your expectations are, but don't stop asking questions it's always good to ask and learn, your learning chamber dimensions which is great, there are a lot of good people on this site that will help, sometimes I over complicate things, but chamber dimensions needs to be learned and it goes a long way in the accuracy game

 

[mausermanbob]

I keep a record of the following measurements for each rifle I shoot and load for:

1. case head to datum where I can just feel contact when closing the bolt (and this is done with a stripped bolt and the primer removed from the case)

2. case head to datum that I set my sizing die for that rifle

3. case head to datum for fired brass

You can accelerate the number of firings it takes to obtain 1. by setting your sizing die high. The will move the shoulder forward and increase the case head to datum length.

If you use a good quality lube and apply it consistently, sizing 0.002" shorter than dimension 1. will work perfectly well. I set my sizing die for 0.001" less than dimension 1 and never have any issues or contact when closing the bolt. YMMV

jepp2

I am a bit light on getting these dimensions.
When you have a chance can you explain a little how I make measurements 1 and 2?
I can use my comparator for 3 I believe, and have done that.
But 1 and 2 sound like a measurement that I'm not sure of how to do?
Appreciate your time and knowledge base.

 

[Ralph Littlefield]

jepp2

I am a bit light on getting these dimensions.
When you have a chance can you explain a little how I make measurements 1 and 2?
I can use my comparator for 3 I believe, and have done that.
But 1 and 2 sound like a measurement that I'm not sure of how to do?
Appreciate your time and knowledge base.

One way to get the case head to datum point on shoulder is to close the bolt on an empty case with a spent primer that is just started into the primer pocket. The bolt will seat the primer and you can measure the dimension from the partially seated primer to the datum point with your Hornady comparator.

 

[DaveTooley]

Start with virgin brass. Range pick up brass will drive you crazy in short order.

 

[mausermanbob]

One way to get the case head to datum point on shoulder is to close the bolt on an empty case with a spent primer that is just started into the primer pocket. The bolt will seat the primer and you can measure the dimension from the partially seated primer to the datum point with your Hornady comparator.

Very good....thanks Ralph!

 

[6MMsteve]

jelenko

Appreciate that.
I got a select match Shilen barrel, Zermatt receiver and decent Crimson Trace scope.
I want to squeeze every good ounce out of that system at the range, I just need to take it ready -steady-go with the reloading. Baby steps.

sounds like you have a nice rifle that's good it should be fun to shoot, making little bugholes, I thought you was talking br 15 but you have a good ground setup for some fun shooting, yes I would go all out on that rifle it could be a beast

 

[mausermanbob]

Start with virgin brass. Range pick up brass will drive you crazy in short order.

Hey Dave
I have a box of unopened Lapua and I'm going to start using some of that for a fresh base line.
Thanks for your thoughts.

 

[jepp2]

When you have a chance can you explain a little how I make measurements 1 and 2?

The method @Ralph Littlefield described is an excellent way to get a start on recording 1. Some folks just neck size until it becomes difficult to close the bolt on loaded rounds. It may take 3+ firings until this occurs. My method for setting die high (so it doesn't bump the shoulder back any) move the shoulder forward as the sides get squeezed in. Like this pic that a member from TFL created to show what happens.



One of the reasons the measurements are important to me is that I may move brass between rifles of the same caliber. I also don't want to have resistance when I close the bolt due to the brass being too long. Without the proper lube, this can result in galling to bolt lugs. The feel is much better with the firing pin assembly removed from the bolt body when checking for resistance.

If I left questions, feel free to PM me. I'll give you my phone number and we can discuss.

 

[JMayo]

I bent up a decaping pin one time !

 

[Coyotefurharvester]

So most importantly(has already been asked) does the sized brass chamber properly? If I have brass that is requiring extra force to close the bolt, a quick adjustment(check) is a 0.002-0.003 shim under the case head in the shell holder and second sizing pass. Let's me know to turn the die in 1/16 of a turn.

 

[mausermanbob]

The method @Ralph Littlefield described is an excellent way to get a start on recording 1. Some folks just neck size until it becomes difficult to close the bolt on loaded rounds. It may take 3+ firings until this occurs. My method for setting die high (so it doesn't bump the shoulder back any) move the shoulder forward as the sides get squeezed in. Like this pic that a member from TFL created to show what happens.

View attachment 1362535

One of the reasons the measurements are important to me is that I may move brass between rifles of the same caliber. I also don't want to have resistance when I close the bolt due to the brass being too long. Without the proper lube, this can result in galling to bolt lugs. The feel is much better with the firing pin assembly removed from the bolt body when checking for resistance.

If I left questions, feel free to PM me. I'll give you my phone number and we can discuss.

Thanks jepp2

I'm going to start drilling down into these posts tomorrow, but I'll keep your offer on the table and will probably be contacting you with more questions.
Thanks for your help

 

[Fast14riot]

Just a word of caution, I dont believe the Lee Challenger press will cam over. It might have little tabs on the handle links to prevent it. So before you go putting tons of pressure on your press, dies, and breech lock bushings trying to cam over, be sure to check. The ram would go all the way up, then back down a little (visible amount) at end of stroke if it cams over.

 

[Uncle Ed]

I've been reloading for about 1 year.
I have a Lee breach lock Challenger loader.
One of the things that I can't get my head wrapped around is on some of my 223 brass that I pick up off the range when I go to resize it with a full length resizer I can't seem to get the headspace below a certain size, according to my Hornady headspace comparator.
Say a range cartridge headspaces at 1.465, no matter how far I crank the die down I can't get it to resize down any lower than like 1.463.
My bolt action rifle shoots the best at like 1.461.
This is a beginner's question, but why is it that some brass I cannot get to headspace below a certain amount no matter how far down I crank the die.
Any help or suggestions would be much appreciated.

Pause at the top of the ram stroke for 3 to 5 seconds and your shoulder location will be more uniform.

Range brass can have been fired several times making the brass harder with more spring back. And pausing at the top of the ram stroke makes the shoulder location more uniform.

 

[dusterdave173]

Rookie here
Man this has been one of the best threads on here in a while--Great solid info to help others that don't know ( like me)
Thanks to all !
I did some stuff I regretted to my first boxes of Lapua brass before I knew better

 

[Webster]

I've been reloading for about 1 year.
I have a Lee breach lock Challenger loader.
One of the things that I can't get my head wrapped around is on some of my 223 brass that I pick up off the range when I go to resize it with a full length resizer I can't seem to get the headspace below a certain size, according to my Hornady headspace comparator.
Say a range cartridge headspaces at 1.465, no matter how far I crank the die down I can't get it to resize down any lower than like 1.463.
My bolt action rifle shoots the best at like 1.461.
This is a beginner's question, but why is it that some brass I cannot get to headspace below a certain amount no matter how far down I crank the die.
Any help or suggestions would be much appreciated.

Never heard of determining accuracy based on headspace (bump) measurements. You cannot shoot good enough to see the difference. If you fire a case and it chambers easily it doesn't need to be bumped. Measure a fired case that chambers easily and you should never bump below this measurement. It wouldn't hurt to anneal every case. I use a torch and I am happy with the results.

 

[mausermanbob]

Pause at the top of the ram stroke for 3 to 5 seconds and your shoulder location will be more uniform.

Range brass can have been fired several times making the brass harder with more spring back. And pausing at the top of the ram stroke makes the shoulder location more uniform.

Ed
Thanks for the insights and the video.
I was making a complete stroke but not pausing at the top of the stroke but dropping it immediately down.
It is a characteristic of brass I never thought of, but does make sense.
I'll experiment tomorrow and update you.

Thanks again

 

[Coyotefurharvester]

The Challenger is an "O" type cast aluminum press, but the die installation is slightly different from other brands. Lee as help videos for their products, one important note from Lee product techs. They recommend when using "range brass" if following the the die installation instructions results in brass that will not chamber correctly-throw that brass away. Dell time in the die is a good idea, I do it even with dedicated rifle brass and rock chuckers( and the mandrel), range brass always "rests" in the die.

 

[Longtrain]

…If you use a good quality lube and apply it consistently, sizing 0.002" shorter than dimension 1. will work perfectly well. I set my sizing die for 0.001" less than dimension 1 and never have any issues or contact when closing the bolt. YMMV

+1

I used to use One-shot for my bulk sizing when I shot XTC and went through lots of cases. Moving to bolt guns and looking to get the best accuracy, I wanted a .002 bump.

Use Imperial Sizing Wax, just a touch goes a long way. Run your die to touch the shell holder, resize, measure…no change, turn the die down 1/8 of a turn, repeat and adjust until you get your desired bump. Lock it in place, resize a few, measure and confirm your results…should be good to go. Different lots and brands of brass will resize differently. Want perfect resizing IMO anneal after every firing, resizing will be so consistent it’s amazing. Remember lube is important, get the feel for using the same each time and you’ll get good results resizing your cases.