Question about measuring headspace

A

andre3k

New member
I just recently picked up a used BR rifle in 6 ppc. I also received a Redding SB FL resizing die and a wilson seater. I know that most PPC shooters FL resize after every firing due to the high pressure loads. I also know that I should bump the shoulder back about .001 in when FL sizing. What measuring tools are you guys using to measure headspace? I had looked at the hornady headspace tool, but then came across this one: http://www.larrywillis.com/

The digital one seems nice but I just need something to get started with for now.
 
I don't measure headspace. I take a fired case from the chamber that I am using and use a Wilson decapping pin. I drive the primer out. You can use a Thingie that Harrels provides with their dies or one that is made with your reamer. Slip it on the neck and measure from the base. Adjust you die until you can measure .001 bump.
Butch
 
As brass bocomes work hardened from beiing fired and FL sized, the die setting in the press must be adjusted so that the shoulder will be bumped. I check to see that I am getting the bump that I am looking for every time I start back through a set of cases, so I need something that is portable. I have the Harrell's brass tool, a short, squared off piece of barrel with the front of the chamber reamed into it, and the Stoney Point/Hornady headspace tool. They all work just fine. Given that I do all of my loading for my 6PPC at the range, I would have little use for a bench tool, however nicely it be made.
 
Not a specific value

The goal is to bump the shoulder just enough, and no more, to remove interference when closing the bolt. A measured .001 may not be enough. It depends on where the contact point of the "device" used to take the measurement meets the shoulder and the angle of the bump die. More thought would reveal other factors as well. Case life often dictates a die adjustment as the "spring back" of the brass increases.

Point is, a specific value for "bump" won't always serve your purpose.
 
great advice

No I's, No me's, and No you should of, Thats it. thanks wilbur
 
andre3k ...

andre3k said:
I just recently picked up a used BR rifle in 6 ppc. I also received a Redding SB FL resizing die and a wilson seater. I know that most PPC shooters FL resize after every firing due to the high pressure loads. I also know that I should bump the shoulder back about .001 in when FL sizing. What measuring tools are you guys using to measure headspace? I had looked at the hornady headspace tool, but then came across this one: http://www.larrywillis.com/

The digital one seems nice but I just need something to get started with for now.
Click to expand...

Something to get started with ??? Use the Hornady tool. It does the job. You may find that's all you're ever going to need. ;)
 
I decided to make the Digital Headspace Gauge after encountering huge numbers of shooters that were not sure what headspace actually was, or why a reloader needed to know about it. The Hornady tool is similar to our gauge. They both measure the clearance that YOUR handloads will have in YOUR particular chamber.

However, our gauge doesn't require using different size bushings or special tools, and it provides uniform downward spring pressure to give consistent readings. Our Digital Headspace Gauge doesn't require balancing your case on the blade of your calipers, and the gauge itself is included.

- Innovative
 
Gizzy

andre3k said:
I just recently picked up a used BR rifle in 6 ppc. I also received a Redding SB FL resizing die and a wilson seater. I know that most PPC shooters FL resize after every firing due to the high pressure loads. I also know that I should bump the shoulder back about .001 in when FL sizing. What measuring tools are you guys using to measure headspace? I had looked at the hornady headspace tool, but then came across this one: http://www.larrywillis.com/

The digital one seems nice but I just need something to get started with for now.
Click to expand...

This is what I use. I call it a Barrel Stub. Most Benchrest Gunsmiths provide a barrel stub with a chamber job. I prefer to set headspace after the case has been fired several times. A newly fire-formed case is not fully formed. Insert the case before sizing and take a reading. Size and insert the case and take a reading.

GW

2f0c6ci.jpg


v4b3n7.jpg
 
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Gary .......

Your method works just fine. However, our Digital Headspace Gauge is not so rickety, and it's quicker and easier to use. Our gauge will work on ANY caliber (case or bullet). The price of your gizmo is definitely more affordable. Our Digital Headspace Gauge will compare case length or AOL in about one second per round. It also compares measurements from the bullet ogive. Every tool has advantages and disadvantages.

- Innovative
 
andre3k said:
I just recently picked up a used BR rifle in 6 ppc. I also received a Redding SB FL resizing die and a wilson seater. I know that most PPC shooters FL resize after every firing due to the high pressure loads. I also know that I should bump the shoulder back about .001 in when FL sizing. What measuring tools are you guys using to measure headspace? I had looked at the hornady headspace tool, but then came across this one: http://www.larrywillis.com/

The digital one seems nice but I just need something to get started with for now.
Click to expand...

The little gizmos made using the chambering reamer is all one needs to determine how much the shoulder is being bumped back. If you are a gadgets person with plenty of money to spend then other tools are available.
 
J. Pendergraft said:
The little gizmos made using the chambering reamer is all one needs to determine how much the shoulder is being bumped back. If you are a gadgets person with plenty of money to spend then other tools are available.
Click to expand...

I bought this gun used off the classifieds so I dont have a barrel stub. But I will have it rebarreled at the end of this season and I'll be sure to ask for it. The rifle came with some 1x fired brass and new brass. The seller was kind enough to include the redding small base die and a wilson seater.
 
Larry

Your head space checker is a nice piece, but keep this in mind.

Most of the answers that we give on this Forum revolve around what works in the enviroment of Match Shooting, which often can be a less than pristine enviroment.

The item that Gary posted the pictures of is what the vast majority of Benchrest Shooters use. It is quick, rugged, and represents the chamber that the case is going in.

True, your tool is more universal. But most Benchrest Shooters have a barrel Gizzy for every chambering. I have one for the 30PPC, 6PPC, 30BR, and 6BR. Cheap, user friendly, and guaranteed not to break if you drop it.:D

But, as I said, you piece is quite nice........jackie
 
Tom G

Sorry if too many "I's" and "Me's", and "this is what I do's" appear in our post.

But one of the main reasons shooters come to this site is to garner information from real Benchrest Shooters who have came upon this knowledge in real World of The Competitive Arena.

Not from some anonymous wanna be who spins a good yarn with a keyboard........jackie
 
Larry, you put out good tools, as you know I have gone to bat for your dies on more than one occasion and will do so again anytime and on any forum.

The only problem with your head space checker is, no one in his right mind would set up such a beautiful tool on a loading bench at the range. Someone comes along and bumps it, it goes to the ground and the fights would be on. While many of us would like to watch the fight, I don't wants to be the guy with tears in my eyes.

That chamber gizzy as it's called, fits in the draw of a shooting box and takes up vary little room, the other measuring tool, you already have in the box.

Without a chamber gizzy, then setting up your die at home using your device would really shine. That is before you hall the loading tools to the range.:D
 
Jackie ............
I'm not sure who you're mad at with your ("I's" and "Me's", and "this is what I do's") statement. (Who's Tom G.?) Not everyone on this site is an accomplished benchrest shooter at this time. Most are interested in learning from helpful benchrest shooters, but there are a whole lot of shooters that will never join formal competition, and that's perfectly OK.

Our Digital Headspace Gauge is not specifically designed for shooters that load at the range. I prepare my cases on a "pristine" bench at home, then I just "pour 'em and cork 'em" at the range. Our digital gauge provides a NEW method of measuring. Most shooters know that it's not the only method. Sometimes new is good . . . .

It's best to not discourage the "wanna be" shooters because they're our best hope for preserving the Second Amendment. Trust me . . . . most non-shooters aren't interested.

- Innovative
 
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Gentlemen ...

andre3k said:
What measuring tools are you guys using to measure headspace? I just need something to get started with for now.
Click to expand...

Above is a synopsis of the original thread. As Andre says, he's looking for something he can use now. Suggestions ??? :)
 
Something I was curious about measuring headspace was how do you know if the case is against the boltface and not the ejector spring?

When you close the bolt and the shoulder is contacting the chamber, what about if you have a small gap between the base and the boltface?

Would this not increase jump of the bullet?

Reason I ask is what's the best way to measure this.

I tried once measuring an aluminum rod from the muzzle against the boltface, then inserted a cartridge with a flush plug in the neck and measured the difference. Then I measured the base to ogive of the cartridge subtracted from the OAL of the case and that gave me the point of contact on the shoulder to the flush end of the neck.

Was just messing around with it but figured it would be worth a shot.

From the one I have seen from hornady, does it overcome the ejector spring presure?
 
gtofan

I am not sure I understand quite what you are saying.

When you fire a rifle, the case takes the shape of the chamber, and minus justr a little bit of spring back, takes up all of the space between the bolt face and the shoulder.

If you use one of the devices that is recommeded in these post, you can accurately measure this distance. You can then run you case through a sizing die and measure exactly how much the shoulder moves back in relation to the face of the case.

I fail to see where the ejector spring tension comes into this equation......jackie
 
When you fire a round, if the case is not against both the shoulder and the boltface, would it not move rearward to the boltface therefore opening the gap from the seated round and the lands, moving back against the spring?

Unless a properly sized case does sit this way, but with about .001-.002 clearance.

So what i'm getting at is are the gauges for measuring headspace, do they measure from a fully compressed ejector spring with the base of the cartridge seated firmly against the boltface and the shoulder touching the chamber?
 
gtofan

We are loosing somthing in translation.

When a rifle fires, the internal pressure inside the case expands the case walls against the sides of the chamber and pushes the shoulder out against the shoulder in the chamber. This, in turn, forces the entire case against the bolt face.

After firing, at normal pressures, the case then contracts a minute amount, allowing for ease in extraction.

Where does the extractor spring enter into this equation??........jackie
 
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