Shoulder / Headspacing questions 6.5 Creedmoor

Pink_Mist

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The issue at hand is that I cannot bump the shoulder because my die is bottomed out. Redding Competition Dies with Shell holder kit.

I am using a .400 dia Hornady bushing on my caliper. This will allow me to take a measurement from the base of the case to the shoulder tangent (where dia is 0.400”)

The saami specs shows the base to shoulder 1.5438” I measure my 3x fired Lapua brass and I have 1.5365” – so I am still 0.0073” from the shoulder after brass is fired formed. (I have sorted my fired brass I have base to shoulder tangent from 1.5355"-1.5365" with 90% at 1.5360") IS this even possible? Fire forming should espand that case to occupy the entire chamber(?)

My case length is 1.911 so I know that I have not grown my brass with only 3 fires.

The information shows that brass has not expanded to fit my chamber. OR my chamber does not meet specs and is under sized. Therefore full length sizing is not possible because the die bottoms out before contact to the shoulder has occurred.

Once the shoulder has made contact I will bump 0.002”

Does my theory seem correct – that I just haven’t fired my brass enough to occupy the headspace or Seekins undersizes their chambers.

I could have a shell holder milled ground down to prevent bottoming out and this would expose the truth of the situation.

THOUGHTS???

1601996695414.png
 
Something else to note. With the FL die bottomed out I cannot flush seat a sized case in my case gauge.

The bolt will close with medium resistance. I cannot definitely attribute this to head space due to the previous statement. The resistance is most likely caused by the expanded base not being completely sized due to the bottoming out. I think I need to modify a shell holder to allow deeper insertion to the die OR I have the base of the die turned down .015” - I can make up for this with my over sized Redding shell holder kit.
 
I figured it out. I need .010 removed from the base of my die.

With the Redding shell holder kit I can climb to the depth with the die bottomed out.

I am .0073 away from contacting the die. I need another .002 to bump. That’s .0093 removed when using a standard hold that is .125”. If I needed to bump less I can use the .127” shell holder as they increase in thickness of .002”

Thanks for letting me bounce this off of you.

I will first alter a 9$ holder and if it works, then the die.
 
Noooooooo! Do not cut your die. Ignore the saami specs! The Hornady tool is a comparative measurement tool, not a gauge. You need to fit the case to your chamber, specs are out of play here. Push the primers out of the cases you intend to check, ideally without pushing them into your sizing die(decap die). Set the sizer up to not bump the cases at all. See if they chamber with the striker removed from your bolt.


You should have a range if cases to do this with, since they’ll vary 1 to two thousandths in fired condition.
 
You should go back and look at the saami spec.

You are talking about yout chamber and quoting cartridge speck it seems.

1.541 shoulder minimum is what I see.

So unless my calculator got fat fingeted looks like your 0.005 under saami minimum?

Did you zero your calipers with the comparitor in place?

My tool has a built in .005 to allow for a champher on all my comparitors to read properly.
If you dont re-zero that would show the exact amount you are off from a saami minimum with your fired brass.

No to say above advice is wrong just letting you know where the missing .005 is in my opinion.
 
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Noooooooo! Do not cut your die. Ignore the saami specs! The Hornady tool is a comparative measurement tool, not a gauge. You need to fit the case to your chamber, specs are out of play here. Push the primers out of the cases you intend to check, ideally without pushing them into your sizing die(decap die). Set the sizer up to not bump the cases at all. See if they chamber with the striker removed from your bolt.


You should have a range if cases to do this with, since they’ll vary 1 to two thousandths in fired condition.
This X1000!!!
 
A.
Every comparator I have has the extra .005 too allow for the champher and must be zeroed out.

B. Have I misread the saami minimum chamber speck?

C. What is the dimension of your no go gauge?

These are for my learning curve not an attempt to throw shade.
 
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Im inclined to also reccomend do not modify the die and explore other causes including human error. Its important to accurately determine your rifles chamber size and distance to the lands. Then resize and load based off those numbers and not necessarily Saami spec.

Using the stripped bolt feel method seems to be the easiest and most accurate.

All the tools really do is give you a way to compare to your chambers pre determined size.

Heres one of my favorite tools for sizing. It has saami, go and no go markings for comparison.
 
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Do any of you have access to a .400 ball gauge? Or any ball gauges of the comparitor datum sizes?

I'll bet if calipers were zeroed out on that and the comparitor assembly put on strait it will measure 2.000 .

It's my theory that all the animosity on comaprators comes from the .005 champher and in reality they are within .0005 tolerance.
 
The saami specs shows the base to shoulder 1.5438”

View attachment 7440097

NO, IT IS NOT

The SAAMI base to shoulder dimension for 6.5 Creedmoor CARTRIDGE is 1.5368 to 1.5438. That's what 1.5438-.007 means. SAAMI uses both one and two sided tolerances in their prints. Why I have no idea.

The SAAMI breechface to shoulder dimension for the 6.5 Creedmoor CHAMBER is 1.541 - 1.551.

If your fired brass only measures 1.5365 base to shoulder datum, I suspect you have an undersized chamber, which needs to be lengthened by .0045" to reach minimum dimension.
 
The Hornady tool is a comparative measurement tool, not a gauge.
How do you figure? It lets your calipers index on the shoulder datum and cartridge base. That's makes it a direct (not comparative) measurement for case base to shoulder.

BTW, something is severely off with those go/no go gages in your pic. They are way the fuck off from the SAAMI chamber dimensions:
1602008367615.png
 
How do you figure? It lets your calipers index on the shoulder datum and cartridge base. That's makes it a direct (not comparative) measurement for case base to shoulder.

BTW, something is severely off with those go/no go gages in your pic. They are way the fuck off from the SAAMI chamber dimensions:
View attachment 7440231
You’re making the assumption that the .400 Hornady tool, which costs 11 bucks, is perfectly .400”, and has no inside chamfer. I’ll trust the precision ground gauges from the reamer manufacture before I trust an janky piece of aluminum. I’ve chambered a bunch of barrels with my saami 6.5 cm reamer, and ALL of the brass I’ve had in my possession over several years is .001-.003 shorter than that Go gauge, right where you’d expect them to be.

More importantly, the OP can comparitively measure virgin and fired cases, and he has a fixed chamber which he can bump into to test his fit. Saami specs are for firearms and ammo/component manufacturers, not precision rifle hand-loaders.



@Snuby642, remember when you were in the OP’s shoes? Forget about the saami spec, that got you nothing but problems. We went over that ad nauseam.
 
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WAAAAAAAAAIT a minute....... I spoke with Redding. 1. yes I have zeroed out my caliper. Yes it's quality and yes its repeatable. I have surface ground gauge blocks accurate out to 0.00005.

The issue at hand should answer most of the rabbit hole questions that are being tossed, which is; The die is bottomed out and is not bumping the shoulder. Redding said they get this phone call every few weeks. The answer, which I agree with is to leave the die alone. Hone a 8 dollar shell holder. Whatever SAMMI specs are does not mean shit, the fired brass is the actual footprint and when 90% of my brass is consistently expanded to exactly 1.5360. It is safe to say my chamber is slightly small than spec and whatever that actually is the dimension that I need to bump .002 from.

@Supersubes

"My brass might be trash if I've been using a standard shell holder?" Explain what you mean please. I don't follow.
NO, IT IS NOT

The SAAMI base to shoulder dimension for 6.5 Creedmoor CARTRIDGE is 1.5368 to 1.5438. That's what 1.5438-.007 means. SAAMI uses both one and two sided tolerances in their prints. Why I have no idea.

The SAAMI breechface to shoulder dimension for the 6.5 Creedmoor CHAMBER is 1.541 - 1.551.

If your fired brass only measures 1.5365 base to shoulder datum, I suspect you have an undersized chamber, which needs to be lengthened by .0045" to reach minimum dimension.
See the posted print from SAAMI.org above?

How did I get to three times fired before I am addressing this? Well because I only started seeing issues the last shooting session. A few random fliers have directed my thoughts to my hand loading process. For the record my 151-200 and 251-300 round hand loads produced 3 - five round 2.25-2.60" groups at 1000 yards. I do not run hot charges and I rarely run into headspacing issues. It was only in the groups of brass that were on their 3 fire where the bolt closing was starting to put up medium resistance.
 
WAAAAAAAAAIT a minute....... I spoke with Redding. 1. yes I have zeroed out my caliper. Yes it's quality and yes its repeatable. I have surface ground gauge blocks accurate out to 0.00005.

The issue at hand should answer most of the rabbit hole questions that are being tossed, which is; The die is bottomed out and is not bumping the shoulder. Redding said they get this phone call every few weeks. The answer, which I agree with is to leave the die alone. Hone a 8 dollar shell holder. Whatever SAMMI specs are does not mean shit, the fired brass is the actual footprint and when 90% of my brass is consistently expanded to exactly 1.5360. It is safe to say my chamber is slightly small than spec and whatever that actually is the dimension that I need to bump .002 from.

@Supersubes

"My brass might be trash if I've been using a standard shell holder?" Explain what you mean please. I don't follow.

See the posted print from SAAMI.org above?

How did I get to three times fired before I am addressing this? Well because I only started seeing issues the last shooting session. A few random fliers have directed my thoughts to my hand loading process. For the record my 151-200 and 251-300 round hand loads produced 3 - five round 2.25-2.60" groups at 1000 yards. I do not run hot charges and I rarely run into headspacing issues. It was only in the groups of brass that were on their 3 fire where the bolt closing was starting to put up medium resistance.
When you say you’re using the Redding shell holder kit, are you talking about the competition kit? If so, Can I assume you are no longer using that kit, and you ran the die down onto a standard shell holder? When you set up the seating die, is it set up to cam over on a standard shell holder, or just touch under zero load?
 
Correct. I have been using a standard shell holder. If a standard produced this issue then adding space is the opposite of what I need and the kit is useless in my situation. I need .0010 under size not over.

Having the kit would be useful only if I removed .010 from the die. Which I am not about to do.

I’ll hand hone a standard holder from .125 down to .115 and verify my results as I go. I have several holders sacrifice.
 
Good picture of proper set up of comparitor and the last picture shows the brass not seated on the face of the tool rather the bore leaving a small void.

A virgin case .0095 low is a lot, but I get .007 often in virgin brass of random brands and calibers.

I now understand the difference between a comparitor / case gauge and precision gauge other than price.

I would like you to measure your comparitor to your know precision go gauge and let us know your result.

I was surprised that 2 of mine were dead on within my 3 calipers +/- .0005 tolerance.

I understand why Hornady doesn't market them as gauges but supprised at the effort they seem to have made in my lucky case.
 
Correct. I have been using a standard shell holder. If a standard produced this issue then adding space is the opposite of what I need and the kit is useless in my situation. I need .0010 under size not over.

Having the kit would be useful only if I removed .010 from the die. Which I am not about to do.

I’ll hand hone a standard holder from .125 down to .115 and verify my results as I go. I have several holders sacrifice.

I use those kits in all cartridge sizes, and know how they work. I was making sure that you had actually gone down to a standard shell holder.


I’ve shown you , using the same tool you’re using, on a go on a no go gauge, and three pieces of brass from quality manufacturers. Do you think it’s a coincidence that your measurement falls right in between a go in a no go gauge? While it’s unclear exactly how much over length your die may be since you don’t have a case it Will bump on, forget the specification. Hone your shell holders down .001 at a time.
 
Good picture of proper set up of comparitor and the last picture shows the brass not seated on the face of the tool rather the bore leaving a small void.

A virgin case .0095 low is a lot, but I get .007 often in virgin brass of random brands and calibers.

I now understand the difference between a comparitor / case gauge and precision gauge other than price.

I would like you to measure your comparitor to your know precision go gauge and let us know your result.

I was surprised that 2 of mine were dead on within my 3 calipers +/- .0005 tolerance.

I understand why Hornady doesn't market them as gauges but supprised at the effort they seem to have made in my lucky case.

The caliper was zeroed on the comparator, and all gauges and cases are flush against the bottom jaw. I do this by rotating the case while the lower jaw contacts it so it finds its self centered and flush against the jaw.
 
Doesn't the Redding competition shell holder set address that very issue? They come in .002 increments up to .010.
I use a Forster press so I just grind my dies if I run into a short chamber.

For some of the other stuff.

Even if the Hornady tool was machined to .400, it has a slight bevel so the the measurement of a go/nogo gauge will always be skewed.
An 6.5 creed go gauge marked 1.5410 measures 1.531 using the Hornady 400 tool.
A 3006 Field gauge marked 2.0577 measures 2.047 using the Hornady 375 tool.

A quick and dirty way I use to calibrate out the bevel on the tool is to zero the caliper with the tool installed then measure a go gauge.
Subtract the measured dimension from the dimension printed on the go gauge, say its .010, remove the tool slide the caliper jaw until
it reads -0.010 and re-zero the caliper. Reinstall the too onto the caliper and now the tool will match the gauge.
 
Good picture of proper set up of comparitor and the last picture shows the brass not seated on the face of the tool rather the bore leaving a small void.

A virgin case .0095 low is a lot, but I get .007 often in virgin brass of random brands and calibers.

I now understand the difference between a comparitor / case gauge and precision gauge other than price.

I would like you to measure your comparitor to your know precision go gauge and let us know your result.

I was surprised that 2 of mine were dead on within my 3 calipers +/- .0005 tolerance.

I understand why Hornady doesn't market them as gauges but supprised at the effort they seem to have made in my lucky case.
The go/nogo gauges are in the first two pictures I posted above.
 
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Doesn't the Redding competition shell holder set address that very issue? They come in .002 increments up to .010.
I use a Forster press so I just grind my dies if I run into a short chamber.

For some of the other stuff.

Even if the Hornady tool was machined to .400, it has a slight bevel so the the measurement of a go/nogo gauge will always be skewed.
An 6.5 creed go gauge marked 1.5410 measures 1.531 using the Hornady 400 tool.
A 3006 Field gauge marked 2.0577 measures 2.047 using the Hornady 375 tool.

A quick and dirty way I use to calibrate out the bevel on the tool is to zero the caliper with the tool installed then measure a go gauge.
Subtract the measured dimension from the dimension printed on the go gauge, say its .010, remove the tool slide the caliper jaw until
it reads -0.010 and re-zero the caliper. Reinstall the too onto the caliper and now the tool will match the gauge.
The Redding shell holder sets are plus dimensions. They hold the case further and further out of the die, opposite of what the OP needs.
 
You’re not as far off as you think. How did you get to 3x fires brass and you’re just now addressing this? Your brass may already be trash if you’d been cramming them down onto a standard shell holder.

View attachment 7440183
View attachment 7440187
Shouldn't you be using the C-375 bushing, not the D-400 bushing?

 
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You’re making the assumption that the .400 Hornady tool, which costs 11 bucks, is perfectly .400”, and has no inside chamfer. I’ll trust the precision ground gauges from the reamer manufacture before I trust an janky piece of aluminum. I’ve chambered a bunch of barrels with my saami 6.5 cm reamer, and ALL of the brass I’ve had in my possession over several years is .001-.003 shorter than that Go gauge, right where you’d expect them to be.

More importantly, the OP can comparitively measure virgin and fired cases, and he has a fixed chamber which he can bump into to test his fit. Saami specs are for firearms and ammo/component manufacturers, not precision rifle hand-loaders.
I know the difference between chamber dimensions for manufacturers and sizing brass to fit one's chamber. I've been reloading almost as long as I've been making precision parts.

Chamber GO and NO GO gages can be anywhere inside SAAMI dimensions. The GO just has to be larger than minimum headspace and the NO GO has to be smaller than max headspace. Just exactly how much is not controlled by SAAMI. It's up to the gage maker.

Your "SAAMI" reamer doesn't set heaspace all by itself. Headspace is not a dimension already ground into the reamer. It's a dimension that is derived by your tool advance in Z and controlled by whichever go/no-go gauges you choose to use which can be anywhere inside the min max headspace range. But you knew that right?

I brought all this up because the OP clearly does not know how to read prints and still can't tell the difference between chamber and cartridge drawings:
The saami specs shows the base to shoulder 1.5438” I measure my 3x fired Lapua brass and I have 1.5365” – so I am still 0.0073” from the shoulder after brass is fired formed.
.

I'm going to take my comparator to work tomorrow and inspect it.
 
Shouldn't you be using the C-375 bushing, not the D-400 bushing?


LOL holy shit.............I didn't even think of that.

He's completely lost. EVERYTHING he's said is null and void since his measurements are complete shit.
 
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I know the difference between chamber dimensions for manufacturers and sizing brass to fit one's chamber. I've been reloading almost as long as I've been making precision parts.

Chamber GO and NO GO gages can be anywhere inside SAAMI dimensions. The GO just has to be larger than minimum headspace and the NO GO has to be smaller than max headspace. Just exactly how much is not controlled by SAAMI. It's up to the gage maker.

Your "SAAMI" reamer doesn't set heaspace all by itself. Headspace is not a dimension already ground into the reamer. It's a dimension that is derived by your tool advance in Z and controlled by whichever go/no-go gauges you choose to use which can be anywhere inside the min max headspace range. But you knew that right?

I brought all this up because the OP clearly does not know how to read prints and still can't tell the difference between chamber and cartridge drawings:
.

I'm going to take my comparator to work tomorrow and inspect it.
When I’m chambering a barrel, I know exactly how to set headspace. You claimed my gauges were wrong. That’s why I posted datum pictures of three different types of virgin brass. The gauges are correct.
 
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Shouldn't you be using the C-375 bushing, not the D-400 bushing?


The reality is it doesn’t matter at all. As long as the comparator datum is not interfering on the radius of the neck shoulder junction or larger than the shoulder diameter or somewhere on its radius. Hornady recommends the .375. The actual datum them for the 6.5 Creedmoor is measured at .400. The OP is using a .400. That’s why I’m using a .400
 
When I’m chambering a barrel, I know exactly how to set headspace. You claimed my gauges were wrong. That’s why I posted datum pictures of three different types of virgin brass. The gauges are correct.
The gauges can be whatever anyone wants within SAAMI limits.
 
LOL holy shit.............I didn't even think of that.

He's completely lost. EVERYTHING he's said is null and void since his measurements are complete shit.
This

but to be honest if you use the Hornandy tool as intended it really would not matter.
Op is making mountains out of mole hills.
Just measure a piece of fired brass and set your die till it reads .002 less than fired brass.
Poof!
Done!
Book specs mean nothing
Your chamber and fired brass is your gospel.
 
Take a once fired case that will easily chamber and knock the primer out. Insert the spent primer in the case.put it in the chamber and close the bolt.extract the case and measure primer to shoulder with your h s gage. This should give you a zero headspace number on your comparator
 
Well that is a point I have.

The saami spec I have downloaded from their site does not have any specs listed for 6.5cm go / nogo.
 
Doesn't the Redding competition shell holder set address that very issue? They come in .002 increments up to .010.
I use a Forster press so I just grind my dies if I run into a short chamber.

For some of the other stuff.

Even if the Hornady tool was machined to .400, it has a slight bevel so the the measurement of a go/nogo gauge will always be skewed.
An 6.5 creed go gauge marked 1.5410 measures 1.531 using the Hornady 400 tool.
A 3006 Field gauge marked 2.0577 measures 2.047 using the Hornady 375 tool.

A quick and dirty way I use to calibrate out the bevel on the tool is to zero the caliper with the tool installed then measure a go gauge.
Subtract the measured dimension from the dimension printed on the go gauge, say its .010, remove the tool slide the caliper jaw until
it reads -0.010 and re-zero the caliper. Reinstall the too onto the caliper and now the tool will match the gauge.

The kit simply increases the the distance from the base of the case to where the die contacts. They start at standard size of .125 and INCREASE by .002”. Thus reducing the distance the case enters the die. I would need undersized holders.
 
Redding offered to inspect and replace the die. They said to send it with some fired brass. I just used a Facing stone and diamond paste and took off what I needed from a holder. Problem solved.
 

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Shouldn't you be using the C-375 bushing, not the D-400 bushing?


i was going to say the same thing and then came across your post.
i'm surprised no one else picked up on this before.
 
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i was going to say the same thing and then came across your post.
i'm surprised no one else picked up on this before.
The OP was comparing datum numbers to the saami print, which uses a .4” datum. It’s understandable why he chose the .4 insert. Problem is it’s a low buck comparator, and not a gauge. Why Hornady, the designers of the cartridge itself and the comparator set decided to recommend the .375 datum, is anyone’s guess. If you put a .375 on, it doesn’t fix anything, just gives you a bigger number, and naturally it doesn’t match the print either.
 
I'm surprised so many of you were immediately dismissing the possibility of the sizing die being too long. I have found this to be a common problem, and have experienced it with RCBS, Redding and Forster dies.

The whole point of using a comparator is to measure your fired brass and then compare to what comes out of the sizing die. If you screw the die down past cam over and your shoulders are not being pushed back you have a problem. While you can screw around with taking material off your shellholder, I have a Co Ax and have no appetite for trying to sort/keep track of which shellholder I shaved off ten thou to make the too long die work.

Redding type "S" dies are pretty popular on the Hide. Speedy Gonzalez is the one who is I believe was the first to come up with a bushing to be used in sizing dies so I think we can agree the originator of the die knows a thing or two about them.

Erik Cortina posted a recent interview with Speedy on youtube where they talk about full length sizing. During the conversation, Speedy mentioned type "S" Redding dies work well, but are often too long. He says they take .015" off the bottom to fix it.

He also says it's better than paying $75 for the Redding Competition die set which will also do the same thing. (sort of implying there might be a reason for them to keep them on the long side)

Glad the original poster got it sorted out.
 
I'm surprised so many of you were immediately dismissing the possibility of the sizing die being too long. I have found this to be a common problem, and have experienced it with RCBS, Redding and Forster dies.

The whole point of using a comparator is to measure your fired brass and then compare to what comes out of the sizing die. If you screw the die down past cam over and your shoulders are not being pushed back you have a problem. While you can screw around with taking material off your shellholder, I have a Co Ax and have no appetite for trying to sort/keep track of which shellholder I shaved off ten thou to make the too long die work.

Redding type "S" dies are pretty popular on the Hide. Speedy Gonzalez is the one who is I believe was the first to come up with a bushing to be used in sizing dies so I think we can agree the originator of the die knows a thing or two about them.

Erik Cortina posted a recent interview with Speedy on youtube where they talk about full length sizing. During the conversation, Speedy mentioned type "S" Redding dies work well, but are often too long. He says they take .015" off the bottom to fix it.

He also says it's better than paying $75 for the Redding Competition die set which will also do the same thing. (sort of implying there might be a reason for them to keep them on the long side)

Glad the original poster got it sorted out.
If they were trying to do that intentionally they’d all be that way. The fact is only a few are, which means they’re just screwing up from time to time. They’re the originators of the comp shell holder setup which is designed to hold the case out of the die and size it less, In easy to swap increments. It’s a good system. That product doesn’t work on an over length die, as the OP showed.
 
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