Which headspace gauge?

[tpcollins]

I'm also reloading .223 for my AR15 and thought I'd pick up a headsppace gauge. The Lyman and Dillon go/no-go gauge looks simple enough as long as it's "machined so spec". The Hornady might be a better choice although not as easy to use versus the go/no-go type.

Just wondering what most here use? Thanks.

[mrawesome22]

The Hornady comparator or RCBS precision mic will let you adjust shoulder bump to a custom fit for your gun.

The drop in gauges are to make sure the ammo will function in any gun ever chambered for that cartridge.

Sent from a Linux kernel.

[F. Guffey]

TPCollins, there are discussions that are not allowed on reloading forums, I could say something like “Think about it” but that has never worked before, so?

I ask a question: What if you a reloader was able to measure a head space gage? Anyone that can measure a head space gage does not need a head space gage, if I had a head space gage I would use it as a transfer, I do not need a head space gage because I make transfers, my transfers are not go, no-go and beyond, I make transfers that are .012 thousandths shorter than a minimum length case from the had of the case to its shoulder to infinity in thousandths.

If a reloader could measure a head space gage they could measure the length of a new/factor/over the counter ammo to determine the length of the case from the head of the case to its shoulder, then they could ask themselves “My new cases when measured from the head of the case to its shoulder are minimum length/full length sized, why not use them as a standard?”

I never bought into the ideal head space? gages came from Mars, I make head space gages and transfers, I am not from Mars.

A good investment is made when purchasing L. E. Wilson gages, there is a limitation, users of the Wilson case gage can not measure a head space gage, the L.E. Wilson case gage is a head space measuring tool. I know that locked up a lot of reloaders, to be more clear, the Wilson case gage will measure the length of a head space gage from the head of the gage to the shoulder/datum in thousandths.

I know, I could say “Think about it” again, that has never worked before.

F. Guffey

For me to agree with mrawesome22 would make both of us wrong.

“The drop in gauges are to make sure the ammo will function in any gun ever chambered for that cartridge”

To think of the Wilson case gage as a drop-on gage is caused by the failure to read the Instructions, and curiosity, yes, a lack of curiosity, on another forum one very heavy poster was using the Wilson case gage as a chamber gage, the instruction read “this tool is not a chamber gage” he has not been civil to me since.

[tpcollins]

I'm not sure what the hell you just said F. but since I'm reloading for an AR15, I'd like to make sure the cases are sized to the proper specs. I can live with fire forming for my .204 and .243 bolt actions but since the cartridge doesn't stay in the chamber for very long, I'm FL sizing these .223 rounds. I judt don't like surprises when I'm shooting . . .

[mehavey]

I'm not sure what the hell you just said ...

ROTFLMAO !!

That said, I'd suggest the Hornady comparators.
Once mounted in the calipers, using is no-brainer EZ.

[1stmar]

+10

[jepp2]

I have Wilson case gages for most calibers I load for but I find the Hornady Lock-N-Load comparators to be better value and easier to get your measurements from. And both are a LOT cheaper than the RCBS Precision Mic, and those aren't available for that many calibers.

Also on AR brass the rim of the case tends to get nicked very easily and this will cause false readings in the Wilson gage unless you dress them up. If you go with the Wilson drop the case into the gage head first to check for burrs before you use it for critical measurements. Just a suggestion.

[tpcollins]

I find the Hornady Lock-N-Load comparators to be better value and easier to get your measurements from.

I was thinking of the Hornady but some yahoo gave a review that the "aluminum" insert was soft and wore down after a few usages - sort stuck in my mind. If I could get just the holder and the "A" insert without spending $40 for a 5 insert set, I might opt for this one.

[F. Guffey]

I must not have made it very clear, head space is not not a topic that can be discussed on the Internet, in the beginning a response started with “Well, you see, there is this datum line and that is how they do it”, it sent everyone to the curb when I informed everyone the datum was not a line, I claimed the datum was a circle/round hole. The circle/round hole for the 30/06 class of chambers is .375” in diameter or 3/8”. Reloaders not able to understand the difference between a line and a circle continued purchasing comparators labeled and sold as head space gages, point? If a reloader understood the round hole/circle concept they could make their own gages.

Back to the claim the L.E. Wilson case gage is a drop-in gage and for that reason it is only used to check to see if the case being checked will chamber in all chambers of that designation. And curiosity? Or go into Internet rage?
No one ask: HOW? or What makes the L.E. Wilson gage a precision gage? “ What is being missed when the Instructions are not read, understood and or followed”? or “IF the L.E. Wilson case gage is so precision and can be used to check a head space gage, what is used to check the accuracy of the L.E. Wilson gage? (I do not expect an answer)

Back to the L.E. Wilson case gage: Drop-in, stand the case on a flat surface (set-up table?) place the Wilson gage on the case so the shoulder of the case supports the gage. then measure the gap between the table top flat surface and the bottom of the gage, I use the most humble tool on the gage family, the feeler gage to measure the gap between the table top and gage to determine the length of the case being measured from the DATUM/shoulder of the gage to the flat surface. The thickness of the leaf determines the length of the case beyond minimum length/full length sized. But still, reloaders are using their finger nails they are guessing as in terms that have no value, most have claim they have dial calipers, most are more concerned about where the dial caliper was made than the developing skills necessary to use one. Point? The dial caliper is also a depth micrometer/height gage, if the case protrudes above the Wilson case gage and a reloader has a dial caliper the reloader can measure the protrusion above the gage if they understand the concept of .000 (zero)

If a reloader has a dial caliper the reloader can check the accuracy of the Wilson case gage, HOW? I know, by now most have allowed themselves to be driven into the curb and in doing so a few have bent wheels, I could say think about it, again, I am trying to think back to the number of times that has worked.

Then there is the absolute insistence on the part of the reloader with a Wilson case gage to ignore the chamber in such a way that leads me to believe the reloader does not think the two (gage and chamber) are related.

Back to my M1917 Eddystone with a chamber that is longer than a minimum length/go-gag length chamber by .011 thousandths, if a minimum length/full length sized case was chambered in my M1917 Edeystone the difference between the length of the case from the head of the case and shoulder/datum and the length of the chamber from the bolt face to the shoulder/datum of the chamber would be .016 thousands. I could say “Not a problem” but, that would would lock most reloadrs up, with the Wilson case gage and a dial caliper of a set-up table or a straight edge and a feeler gage I measure the case head protrusion, in the perfect world I want .014 thousandths case head protrusion from the Wilson case gage.

Keeping up with more than two thought at a time, the gage and chamber: If my chamber is .016 thousands longer than minimum length/full length cases from the bolt face to the shoulder of the chamber ‘AND’ IO add .014 thousandths to the case length between the head of the case and its shoulder I add .014 thousandths to the length of the case, when using the Wilson case gage with .014 thousandths, the case head will protrude .014 thousandths and the neck will be flush with the top of the gage. Back to ‘not a problem’ for most reloaders the length of the case has nothing top do with the length of the chamber from the bolt face to the shoulder of the chamber.

The Wilson case gage measures the case length (neck) from the shoulder/datum to the mouth of the case, it also measure the length of the case from the datum/shoulder back to the head of the case. Nice to know, the Wilson case gage uses a radius, meaning the case does not set on a shoulder in the gage, the case sets on a radius. Curiosity? I placed a Wilson case gage on a block of lead, dropped a case into the gage and with a flat/round punch I drove the case in to the gage, the case was driven into the gage as though the case collapsed with little effort, I remove the case, the shoulder of the case took on the image of the datum/radius of the gage with a perfect concaved shoulder.

Matters not what gage you purchase, if you purchase the Dillon head space gage and some how manage to be able to determine if it is accurate you will find (as we all know) it will chamber and allow the bolt to close, again, head space and gages is a topic that can not be discussed on the Internet, I need only one head space gage, the go-gage to measure the length of the chamber from the bolt face to the shoulder of the chamber in thousandths, If you purchase the no go-gage you will discover the bolt will not close, but the gage will not indicate ‘by how much’.

Then there is the rumor a smith at the Utah Arsenal used one gage, rumor has it he used the field reject gage to measure the length of the chamber on all M1917 30/06 chamber from the shoulder/datum to the bolt face.
Today, there are those that claim my M1917 Eddystone has .016 thousands because he closed the bolt on the field reject gage. I claim I can check the length of the M1917 chamber with a 280 Remington minimum length/full length sized case, think about it, the Remington 280 case length is .051 thousandths longer from the head of the case to its datum/shoulder than the 30/06, meaning we should know the bolt will not close.

I form 30/06 cases from 280 Remington cases, no fire forming, form first then fire.

F. Guffey

[mehavey]

The Wilson (single gauge) and the Hornady (6-gauges) case sets are pretty much the same price, ~$30.
(See Amazon, Midway, etc)

You will never look back having gotten the Hornady set, and you will most likely never have to buy
another gauge given the multiple inserts they give you.



postscript: Ignore anyone saying that the aluminum insert "wear." Maybe if your crunch things
togther in a shop vise, but not otherwise in any semblance of normal use.

[jdillon]

For gas guns, I have found the RCBS Precision Mic the most accurate in measuring the fired case from the base to the shoulder since during the ejection cycle the brass can deform. The Wilson and Dillon case gauges do a great job of letting you know whether the sized cases are in spec. Not all chambers are the same and if you want to adjust you dies so your brass is sized properly for the chamber in your particular rifle the the RCBS Precision Mic or other similar tools will do the trick. Personally, I set my dies for my gas guns from .003 to .005 less than fired brass.

[tpcollins]

JDILLON - how do you:


"Personally, I set my dies for my gas guns from .003 to .005 less than fired brass".


I have Lee dies and just bought a Dillon set for .223. The instructions for both say with the ram up, screw in the die until it touches the shell holder. Do you screw the die in more and somehow the "cam over" drives the case further into the sizer? I would think the shell holder plate would limit this, thanks.

[Clark]

I prefer to get a lifetime supply of brass, measure them, and use a piece of brass as the head space gauge.
That is on MY lathe.

When my little brother and his lathe are involved, I pay for a go gauge from Forster.
He does not seem to understand my hand waving.
Let him have a SAAMI sloppy chamber.

[PawPaw]

And here I thought that a headspace gage was used to set the barrel into the receiver, or to test an assembled rifle to make sure that it is assembled properly. They normally come in three gages, GO, No-GO, and Field.

Y'all are talking about case length gages, which is something different entirely.

Oh, Hey, Frank! Haven't seen you around here in a while.

[tpcollins]

Thanks PawPaw, that's exactly what I was referring to but too many articles online were calling it a headspace gauge and I didn't know the difference.

But I took Unclenick's advice and just ordered the RCBS Precision Mic and I have a halfazz idea how to check fired rounds and compare these to sized rounds - I think . . .

[mehavey]

Y'all are talking about case length gages, which is something different entirely.

Nope -- the Hornady and Wilson gauges being discussed are in fact being used as headspace gauges. (Granted, the Hornady set are in fact "comparators," but they are measuring a variation on headspace.)

We can get into all sorts of semantic definitions -- and yes I have true rifle headspace gauges downstairs (the biiiiiig sets from Forster for both the 308 & 30-06 case family).

The Wilson & Hornady sets are used on the cartridge case, and therefore give you the headspace (base-to-shoulder-datum-line as Mr Guffey righty points out) for the case. The shooter then compares that dimension w/ the SAAMI spec and/or the actual chamber measure of its dimension.

It's sorta like asking: do I have a size 11½ foot, or an 11½ shoe ?
Answer: Yes (if I'm smart)

[jdillon]

TPCollins:

I load .223 on a Dillon 550B and you can follow the instructions which will size the case but potentially oversize it for your particular rifle. In setting up the die on my press, I took a batch of fired cases, lubed them, and then ran them through the press. Using the RCBS Precision Mic, I gradually adjusted the die until the proper headspace was achieved which was .003 to .005 less than the fired case. Then a I ran a number of cases through the press to confirm the measurement. Once I was satisfied that I was consistently sizing to the proper length, I tightened the lock ring and checked again. Since I have a fair amount of .223 brass, I simply discarded the cases used to adjust the die.

If you use the same case to adjust the die to the proper setting, don't be surprised if the next case you run through the die gives you a different measurement. The only way to check your final setting is to run an unsized case through the die. I have noticed the same issue with my single stage press for my non-gas guns. Also brass from different manufacturers will yield slightly different measurements with same die setting. Work hardened brass will do this also.

As far as using the RCBS Precision mic, don't worry about the reading on the scale not going to zero. This is just a relative scale and what you are looking for is a consistent measurement from case to case.

[tpcollins]

JDILLON -

In setting up the die on my press, I took a batch of fired cases, lubed them, and then ran them through the press. Using the RCBS Precision Mic, I gradually adjusted the die until the proper headspace was achieved which was .003 to .005 less than the fired case.

So the bottom of the die is somewhere being flush against the shell holder and some distance away from the shell holder?

[Clark]

tpcollins

So the bottom of the die is somewhere being flush against the shell holder and some distance away from the shell holder?

There ought to be a term for that space:
Die space
Die to holder gap
shoulder bump back off
Screw a die and feeler gauge

[F. Guffey]

“So the bottom of the die is somewhere being flush against the shell holder and some distance away from the shell holder?”

Determining the length of the chamber first then transferring the measurement to press, die and shell holder is for a very few.

For most it is impossible to determine the relationship between the chamber from the bolt face to the shoulder of the chamber (datum) and the chamber created when the die is adjusted to the shell holder from the shell holder deck to the shoulder of the die (datum). Most do not understand the concept of minimum length/full length size and a chamber that is go-gage length.

I am the fan of transfers, standards and verifying.

“There ought to be a term for that space:
Die space
Die to holder gap
shoulder bump back off
Screw a die and feeler gauge”

There is a term used by reloaders on forums, it is referred to as taking a wild guestimate of a turn, tad, smidge, little bit, fractional turn converted to degrees, fractional turns converted to thousandths etc.,

Again, I use a feeler gage, the most humble of tools, no guestimates, the feeler gage is a transfer , it is a standard, after making adjustments the feeler gage is a verifying tool. Redding calls the feeler gage a thickness gage. Redding will have nothing to do with adjusting a die off the shell holder, they make Redding Competition shell holders, using them gives the reloader 5 choices from +.002 to +.010 thousandths. I claim the Redding Competition shell holder is nice but not necessary, I have 10 choices between .000 off the top of the shell holder to .010. Before the Redding Competition shell holder reloaders ground the bottom of the die to increase the ability of the die to reduce the length of the case from the head of the case to its shoulder. Before the Redding Competition shell holder reloaders ground the top of the shell holder to increase the ability of the die to reduce the length of the case from the head of the case to its shoulder, not necessary, all they had to do was raise the deck height of the shell holder with a feeler gage.

I said there are a few that do not insist the die has to contact the shell holder when sizing a case, I do not insist the die must contact the shell holder when sizing, to adjust the die off the shell holder all I need to know is the length of the chamber, again, I form first then fire.

From the beginning I insisted the head space gage?? sold by Larry Willis and Sinclair/Hornady was a comparator, head space, always described in lofty terms, I am concerned with the length of the chamber from the head of the case to its shoulder, I am conserened with the length of the chamber from the face of the bolt to the chamber’s shoulder, and datum is not a line, it is a round/circle hole.

I control the length of the case with the gap between the die and shell holder even when there is no gap, without grinding the die and or shell holder I size/form cases for short chambers, for the 30/06 I form/size cases that are .017 thousandths shorter than a minimum length case, that would be .012 thousandths shorter than a case that a go-gage length chamber from the bolt face to the shoulder of the chamber. .

F. Guffey

[Bart B.]

Well now; gauges.

They're like rifles. So maybe we should prefix them in speech and written words with the type and/or use they'll be used for. Who knows; maybe we won't confuse ourselves and others by calling both types just a headspace gauge.

It's confusing also because in the world of measuring, a "gauge" typically refers to a tool with a fixed dimension that's used on something to find out if something fits or does not fit it's measurement. And a "micrometer" typically refers to a tool that measures somethings dimensions; once the dimension's noted, it's compared to a specified dimension of something to see if it's the same or different.


Chamber headspace gauge; a steel gauge that's a fixed dimension from its head to the reference point where it mates with the same place in a barrel's chamber. "NO GO" gauges are typically in three sizes; GO is the SAAMI minimum length one, NO GO is the SAAMI maximum one and the FIELD one is the absolute limit for safety. For example, this one for a ..358, .308, .243 Win.: http://www.brownells.com/.aspx/pid=6...DSPACE-GAUGES#

And this one for a belted magnum: http://www.brownells.com/.aspx/pid=2...DSPACE-GAUGES#


Case headspace gauge; a measuring tool that measures the distance between the case head and the reference point on the case shoulder. It's used to compare cases ready to fire to fired cases to see what difference there is. Also used to measure fired cases both before and after they're full length resized to see how much the fired case shoulder was set back. Examples are the RCBS Precision Mic which measures something plus or minus a reference. http://www.brownells.com/.aspx/pid=3...Headspace-Tool

and the Wilson case gauge which compares case dimensions to a standard: http://www.brownells.com/.aspx/pid=3...son-Case-Gauge

F. Guffey; please don't get carried away with this one, just let it go. I'm trying to help someone learn something.

[Bart B.]

Clark thinks there ought to be a term for that space between the shellholder and die. 'Twas told decades ago that space was called the "die offset" and was only accurately measured when a full length sizing die had a case in it with the press's ram all the way up putting maximum spring on the press. I don't use that term, but it's sounded good to me over the years.

Unless the shell holder actually stops against the die's bottom when full length sizing a rimless bottleneck case, the resultant case headspace will vary a few thousandths due to how much the press springs for the lubricant between the die and case.

[Clark]

Bart, 38 years ago at the U of WA physics dept a Chinese born physicist discovered a left hand corkscrewing sub atomic particle in the bubble chamber. He wanted to name it a "screw off", but an American born physicist would not let him. Being the laziest and worst freshman in honors physics, I felt cheated.
I saw my chance to riff on a new name in my last post.
But now I guess I have to call it "die offset"

[Bart B.]

Clark, I've thought about this issue. "Die to holder gap" is a good expression now that I've assesed its true value in naming conventions. It's got more meat on its bones of substance than what I was told. And it could be shortened to "die gap" and still be meaningful. I like it much better than "die offset."

The reloading industry has lots of terms that are often misused by reloaders. Had a discussion with an RCBS rep about "partial neck sizing" some years ago. You wouldn't believe some of the issues customers had asking him about what that really does to bottleneck cases and their adamant claims that the body wasn't sized at all by this process. He thought it should be called "shoulderless" sizing as that's the only part of the fired bottleneck case that doesn't get its dimensions changed but only its location on the case. Then maybe customers would understand.

[amamnn]

Who the hell unlocked the asylum door? If I were moderator here I would delete all replys except for PawPaw and ban this Guffy character for life if for nothing else, verbosity and malaprop-age.