New Digital headspace gauge

What is the measured bump required to get to feel good with your FL die?

Also, some, who are not part of the work a small set of cases all weekend crowd, may be under the impression that once a die is set that it can be left at that setting as long as the press, shell holder, die and rifle remain the same. This is not the case. As the number of firings and FL sizings increases, the brass becomes increasingly work hardened, requiring resetting the die to achieve the same bump. Another source of problems in this area is uneven factory annealing, which can cause excessive bump variance, at a given die setting, even when the cases are from the same lot, and have the same number of firings and sizings. A friend ran into this with Winchester brass that he uses in a custom 7mm WSM. Annealing the cases to a quarter inch below the shoulder solved the problem.
 
I KNOW that some folks try to "bump" with a FL bushing die and that causes problems. There is a short section of the neck that does not get resized because it does not enter the bushing or bushing has a radius on the inside diameter. Also, there is a portion of the shoulder that does not make contact with anything, the die is larger than the neck where the shoulder ends.
Another problem, maybe, is that the chamber has a sharp corner at the shoulder/neck juncture but there is a radius at that point in the FL die. Again, that leaves a small area that does not make contact with any surface of the die.

I like to make a "gizzy" or chamber gage that has the neck are opened up .025-.030 larger than the neck size of the chamber. That insures that I'm only checking the shoulder to base relative size based on the datum line. I use small shims (.001-.005) behind my "GO" gage in the rifle to determine what my chamber depth really is. I then use a HS "GO" gage as a master gage to set my caliper when checking for the amount of "bump". I like "GO" plus about .003 for chamber depth.
It works for me and a number of friends. YMMV.

Opinion of one
 
Boyd .....

+1 again

You explained it perfectly. Uniform brass hardness creates the most detrimental effect, and it's a good idea to also verify the final result.

- Innovative
 
Jay of Idaho, I am going to assume I have the luxury of disagreeing. I can not help you with the techniques that work for you, if there are other options please it is not about disagreeing, it is about other options.

If I understand you correctly "I like to make a "gizzy" or chamber gage that has the neck are opened up .025-.030 larger than the neck size of the chamber" the 'Gizzy" would not chamber unless you you are using the bolt camming action to size the neck in the chamber, if you want to neck up a case as in 30/06 .025 to .030 thousands, use a 338/06 or 35 Whelen sizer die, but if you are saying the neck is in the way cut it off, forming/trim dies make short work of that task, or neck the "Gizzy" down as in a Gizzy for the 338/06, 8/06, 30/06, 270 W etc., a gizzy/test case (sorta poor man's gage) would be a 25/06 because the neck would not touch the chamber. Then there is the part where it is believed pulling the sizer ball back through the neck when the ram is lowered lengthens the case, the neck lightens when sized down, the neck shortens when sized up.

Moving the shoulder forward without firing is the difficult part when making gizzies, when possible, start with a case that is longer from the head of the case to it's shoulder than the chamber from the face of the bolt to the shoulder of it's chamber, as in 280 Remington cases when compared to the 30/06 family of chambers, the 280 Remington is longer from the head of the case to it's shoulder than the 30/06 by .051 thousands. When forming cases (before firing) for the 30/06 it is a 'can not miss' if the hand loader knows when to stop. When moving the shoulder back the case is going from the press to the chamber, if the case is necked down or has the neck removed there can not be an interference beyond the shoulder of the case.

Adding shims, if the shims are added to the gage dimensions as in .003 and if this +.003 is transferred to the press the case when sized will be go-gage length +.003, if the chamber is the perfect go-gage chamber the case will require a .003 crush when the bolt is closed or chamber with .000 clearence if the chamber was head space was .008, if the 'gage'? is the size of commercial ammo or equivalent to a case that is minimum length and the chamber is the perfect go-gage size the shims would work, all of my sizing is done with the press, shell holder and die, if there is no correlation between the 'measuring' and the press adjustment most of the measuring is busy work or just satisfying a curiosity.

I have an Eddiestone M1917 that has a chamber that is longer than the perfect full length case (commercial ammo +,- .001) by .016 thousands, new cases fired in this rifle will form cases with the shoulder .015 thousands ahead of a perfect case or .010 thousands longer from the head of the case to it's shoulder than the length of of a perfect go-gage length chamber from the face of the bolt to the shoulder of it's chamber. To fire this rifle without head space issues, I form cases using 280 (new) Remington cases by adjusting a 0.20 gap between the shell holder and the bottom of the die first, then decrease the gap and continue sizing until the formed case chambers. The gap, when measured, between the shell holder and bottom of the die allows one measurement to be taken from the chamber to the press and back to the chamber, to satisfy a curiosity I could measure the length of the formed case from the head of the case to it's shoulder, with any number of comparators, regardless of the indicated reading, the press, die and shell holder when adjusted determine the length of the case, On the other hand if I fire first then measure I could use a comparator to determine the effect the chamber had on the fired case,

Other options, there are options to moving the shoulder forward with out firing, moving the shoulder forward is a matter of firing the case as in fire forming, I form first then fire as in determine the effect the chamber will have on the case before firing then take that measurement from the chamber to the die, press and shell holder and back to the chamber.

F. Guffey
 
F. Guffey said:
Jay of Idaho, I am going to assume I have the luxury of disagreeing. I can not help you with the techniques that work for you, if there are other options please it is not about disagreeing, it is about other options.

If I understand you correctly "I like to make a "gizzy" or chamber gage that has the neck are opened up .025-.030 larger than the neck size of the chamber" the 'Gizzy" would not chamber unless you you are using the bolt camming action to size the neck in the chamber, if you want to neck up a case as in 30/06 .025 to .030 thousands, use a 338/06 or 35 Whelen sizer die, but if you are saying the neck is in the way cut it off, forming/trim dies make short work of that task, or neck the "Gizzy" down as in a Gizzy for the 338/06, 8/06, 30/06, 270 W etc., a gizzy/test case (sorta poor man's gage) would be a 25/06 because the neck would not touch the chamber. Then there is the part where it is believed pulling the sizer ball back through the neck when the ram is lowered lengthens the case, the neck lightens when sized down, the neck shortens when sized up.

(Much of post snipped)

F. Guffey
Click to expand...

Evidently, I totally blew it in my explanation of a "gizzy".

What we call a "gizzy" is a simple accessory that allows one to check several things when reloading. It is a short section of barrel that has had the chamber reamer run in far enough to get most of the shoulder, neck, freebore and leade, leaving a section of rifled barrel ahead of that area. The gage can be used to determine if loaded rounds will enter the chamber and if the bullet is touching the lands.
A second "gizzy" is made but the neck and everything forward of it are reamed out to about .025-.030 larger than original. This tool will touch only the shoulder on a case, no contact with neck area to give false readings. A caliper is used to measure from base of case to end of tool. I usually make this measurement with the "GO" headspace gage and engrave that number on the tool.
You can now measure a fired case and a case that has been bumped. I find this the most accurate way to determine the amount of "bump" that the case is receiving. A set of the +.002-+.010 shell holders from Redding can be helpful in getting the desired amount of bump.

This works well for a number of my friends and myself. YMMV.

Jay
 
Boyd Allen, if in my possession I find a die with the lock ring secured to the die, the die is not my die, I adjust the die every time.

Sizing number count, the perfect case for sizing is new then once fired, brass does not have a memory of what it was before it was fired, it does have an ability to recover, as the case is fired multiple times the recovery is hammered out of it and the rules for sizing change if not annealed, I do not go along with the 'cases are not full grown until they have been fired 5 times', I do believe the case has had the ability to recover hammered out of it. As to sizing, is is mindless to adjust the die down to the shell holder with a 1/4 to 1/2 turn after contact, that is full length sizing, I avoid sizing even if it is full length neck sizing with partial body support and again I am a big fan of determining the effect the chamber will have on the case before firing. not after by measuring the case for the effect the chamber had on the case.

F. Guffey
 
Jay in Idaho, I cut barrels (tomato stakes) down to a manageable size then cut chambers in what is left, gizzy? I have 62 chamber reamers,, increasing the neck diameter of the gage, to me would be the same, cut one chamber gage in 338/06 and use it for 8/06, 30/06, 270 W, down to 25/06, and there other ways to transfer the measurement from the chamber to the press. Redding shell holders, 5 for $60.00, when I run out of options and grinding the bottom of the die and or top of the shell holder is not one.

or cut the chamber gage to 35 Whelen to include the 338/06.

Thank you for taking the time.

F. Guffey
 
If your sizing die and chamber are a proper match, you can arrive at a serviceable die adjustment using the rifle as your gauge. BUT if they are not, by the time that you get the feel that you are looking for, you will have bumped the shoulder back too far, and you will be on your way to an eventual case separation, and without a way to measure bump, you won't know that you have moved the shoulder too far, until the damage is done.

Furthermore, shooters ofter fail to appreciate how small of a fraction of a turn on a die it takes to change bump by .001. With 14 threads per inch, one turn moves the die a little over .071", which means that to change your bump by .001 you only need to move it 1/71 of a turn. Generally we have no way to accurately determine that we have achieved this small degree of rotation, except to look at the shoulder bump that it has created, which requires a gizzy, Stoney Point or Sinclair tool, or this electronic readout tool.

With all of the talk about moving the die 1/16 turn at a time (which turns out to be about .0045") until the correct feel is achieved, I think that it is easy to see how one could overshoot the desired amount of bump.

We post on a forum that speaks to the entire world, and directions that may work under a given set of conditions, may not be a good fit for another, and the reader may not know enough to take this into account. That is why I will always say, and write, measure bump; don't do it by feel.
 
Considering the forum this is on

I am going to agree with you. There is a big learning curve to get to where one has some idea of what they are doing. These kind of discussions always seem to esculate beyond where people posting in them should take them, myself being that person. All I wanted to say was I thought it was a useless device; useless to me. Probably one should never offer an opinion that was other than positive Eh? I'll delete my posts.
 
Boyd .......

+1 100%


Pete ......

If our Digital Headspace Gauge is useless to you, it's only because you hopefully have another method of accomplishing the same thing. Our gauge is much easier to use (and understand) for most people.

Our Digital Headspace Gauge is a NEW method (one of many) that will work. Take your pick, but don't try so hard to shoot it down for shooters that want to learn NEW things.

Example: Back in the day ..... marking cases with soot from candles was the accepted method (it was most popular just before WW1).

Some people just don't like new things, and that's fine with me. However, some NEW things are very much improved. Judging from sales ..... this is one of the good ones.

- Innovative
 
Larry Willis said:
Our Digital Headspace Gauge is a NEW method (one of many) that will work.

- Innovative
Click to expand...
This method is not really new at all - except possibly for this particular application. :D

Like I'd mentioned before, the industry I work in has used it for decades. But one thing is certain in controlling the quality of anything - If you cannot measure it in some way, you cannot control it, and the more accurately the better.
 
Vibe .....

+1 except for reloading. That's why our Digital Headspace Gauge is being patented with the "adjustable V-block".


- Innovative
 
I will assume you are refereeing to reducing the diameter of the flash hole, by following advice I take it the case head is a 'no touch zone', Outside of guns, smithing and reloading when a hole, guide, etc., is too large in diameter and crushing to reduce the inside diameter is not an option they knurl the hole to reduce the inside diameter and then ream the hole/guide/bore back to standard, problem, the primer pocket is shallow.

If the primer pocket has gotten loose or larger in diameter, what effect has the expanding force had on the flash hole?

I have had no interest in flash hole sizing, I did consider doing something with 1,500 new unfired 8mm57 Berdan cases, reducing the outside diameter was not a consideration, although brass is solid it is also a fluid meaning it will flow, swedging the head of the case will reduce the outside diameter, swedging will also increase the distance from the case head to the top of the web. I considered Berdan primers, The Ole' Western Scrounger said he would love to sell the primers, but at .17 cents each the primers were not a bargain.

Loose primers, we spend a lot of time on removing crimps from military cases, why not go back to the crimp, Remington had a full circle head upset crimp (lot of guessing goes on as to what that was about) a mandrel could be used inside the case for support and an upset tool with a circle could be used to move the brass around the primer to secure it. The 'ring' crimp 'stamping tool?' when hit would move or forced the metal to flow down, in against the primer and out, or the crimp tool could be a die that would put dents around the primer, the dents would move the metal in and around the primer to secure it.

The most practical 'for reloaders' would be to have primer manufactures to make over sized primers, then comes the rational for not making over sized primers, if they made primers for cases that have been fired to the point the primer pocket has expanded to the point it will not hold a primer and the case head is a 'no touch zone' they want no part of finding out what happens when a case is used beyond common seance, then there is the possibility of 'soft brass', when the primer pocket will not hold a primer, get a bigger primer? And then there is the heavy load that can expand a Boxer primer pocket to the point it will not hold a Berdan primer.

Case head and loose primer pockets, if the brass is fluid and flows when fired the flow is not only out away from the primer it also flows back against the bolt face, at some point the case head thickness from the case head to the top of the web is reduced, the only measurement discussed on forums is case head expansion (.0002 normal?) as though that is the only event, tools gathering dust, I have a flash hole gage, like everything else, If I do not measure first then fire, the tool becomes one of those tools that is nice to have.

When purchasing cases from the range I use it as a reject tool for cases that are not 'once fired'.

Tools can be/are made to reduce the case head diameter, a small base die is not one of them, military case head thickness as in 30/06 is .200 +/-, RP commercial case head thickness is .260 +/-, of the .260 .125 of the case head + the radius at the bottom to the sizer die does not get sized, or as much as .140 of the case protruding from the bottom of the die, when the case is sized, by design does not touch the 'no touch zone'.

F. Guffey
 
Forgive, 'I will assume you are talking about reducing the diameter of the primer pocket.....

Sorry about that,

F. Guffey
 
It's not that I don't like new things

Larry Willis said:
Boyd .......

+1 100%


Pete ......

If our Digital Headspace Gauge is useless to you, it's only because you hopefully have another method of accomplishing the same thing. Our gauge is much easier to use (and understand) for most people.

Our Digital Headspace Gauge is a NEW method (one of many) that will work. Take your pick, but don't try so hard to shoot it down for shooters that want to learn NEW things.

Example: Back in the day ..... marking cases with soot from candles was the accepted method (it was most popular just before WW1).

Some people just don't like new things, and that's fine with me. However, some NEW things are very much improved. Judging from sales ..... this is one of the good ones.

- Innovative
Click to expand...

I love them but - - - - -
 
F Guffey,

I've got to take issue with some of your stated facts. You use some terms and make broad statements without defining anything. Lots of people get their information here. Feel free to show me wrong using logic or clarify your positions/statements.

Brass is not a fluid. Window glass has been called a "viscous fluid" and could more rightly be described thus but brass is not...... it doesn't "flow." It doesn't "flow back to the boltface," in fact this whole paragraph regarding "flow" etc is misleading.....

your quote

"Case head and loose primer pockets, if the brass is fluid and flows when fired the flow is not only out away from the primer it also flows back against the bolt face, at some point the case head thickness from the case head to the top of the web is reduced, the only measurement discussed on forums is case head expansion (.0002 normal?) as though that is the only event, tools gathering dust, I have a flash hole gage, like everything else, If I do not measure first then fire, the tool becomes one of those tools that is nice to have."

point-by-point:

No, brass doesn't flow back against the boltface. It STRETCHES there, and bounces back some. Crookedylike, because it's stretched beyond it's yield point. Or are rubber bands and balloons and pieces of steel wire also "fluids?"

Case heads don't get thinner from casehead to top of web, not in a way that can be measured. There is no "top of the web," this area just fades together until distinction is lost. There is no danger of caseheads getting thinner enough to cause any problems.

What forums??? Any forum "discussing " measurements of .0002 on brass caseheads is out to lunch. And what would .0002 do? What's the significance of the measurement of ".0002".... in fact, how would you measure that?? I know about 4 people on this earth qualified to "measure" to this spec and all of them would ask "measure to WHAT?" BTW I've got competitive rounds that have been fired 15 times and show about .002-.003 of expansion and they've stopped moving. I'll probably fire them 30-50 more times before I throw them away.

Where do you buy a "flash hole gauge" and what does it measure? And what do you use it for so it's not "gathering dust?" This sort of information needs to be clarified not just thrown out there as "this is how I do it. Y'all are just not getting it done right..." without explanation.



But back to brass "flow."


This old bit of nonsense about brass being "a fluid" has been around forever but that doesn't make it true. Peening of steel surfaces isn't described as fluid movement, nor is steel described as a fluid. Displacement is not necessarily flow and using flow to describe the migration of cartridge brass can and has led to some dangerous misconceptions. Like the idea that "chamber pressure cause brass to flow into the neck"........ utter nonsense. And it blocks one from the real problem, the elimination of brass "flow," the proper maintenance of the brass cases.


opinionsby

al
 
This device is nice, and should measure shoulder bump on muultiple calibers. I use a Redding Instant Indicator which does the same function, but you need to purchase individual inserts by caliber.
 
Am I undrstanding this correctly

you put the fireformed case in this ,dial it then adjust your reloading die so you have the same reading on your resized handload case and you are good to go
Is this correct ?
Is it only used it with your FL die ? and what about using it with the neck die ?
 
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