Shoulder / Headspacing questions 6.5 Creedmoor

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 use what is recommended and haven't run into any issues, yet.

forster make a really nice datum line comparator and might of helped the OP better measure.

i'm sure there is a better mouse trap out there if one wants to spend up big. yes the hornady isn't the most expensive but it does work, maybe not how the OP wanted it to.

sometimes things are better left under-thought instead of over-thought when it works.
 
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.
You are not following how the Comp shellholders work. They are designed to allow the cases to be inserted farther in to the to die.

If you have a die that is too long you can:
  • Remove material off the die yourself or send in to the manufacturer with fired brass who will do it for you
  • Remove material off the shellholder
  • Buy the comp shellholder kit which reduces the size of the shellholder in .002 increments from the industry standard
As I mentioned, it's not a 1 in a million problem. It's surprisingly common. And Forster, RCBS and others do not offer custom shellholders. They have relied for years on customers being unable to measure if their product is working correctly.
 
i use what is recommended and haven't run into any issues, yet.

forster make a really nice datum line comparator and might of helped the OP better measure.

i'm sure there is a better mouse trap out there if one wants to spend up big. yes the hornady isn't the most expensive but it does work, maybe not how the OP wanted it to.

sometimes things are better left under-thought instead of over-thought when it works.
I think the Hornady tool is perfect for the intended use. It’s quick and plenty accurate.
 
Tomayto/ tomahto

looks like fun :ROFLMAO:

1602040078473.jpeg
 
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ok, so i finally caught up on the posts and so the die is too long. at least the OP sorted it.

i would of snapped it long ago and got a refund and bought something else that doesn't need modifying.
 
Glad the O/P got it figured out. I'm currently dealing with the same thing with a 308 F/L die.

For those that haven't used a Hornady comparator, I've been using one for many years, way back when it was Stoney Point. I also noticed I wasn't getting "SAAMI" measurements on my fired & resized cases.

I was fortunate to have a Gunsmith friend that let me come to his shop and let me use his Go gauges. When I measured the 308 win. 1.630" GO gauge with my .400" insert, I got a reading of "1.611". This was the old, original .400" insert. I happened to have a newer, recent manufactured .400" insert. That insert measured "1.622" on the GO gauge.

What that showed me was the old .400" insert has a .019" chamfer in it and the newer .400" insert has a .008" chamfer. I happened to have a 308 Win. RCBS Precision Mic that I picked up at a garage sale for $15.00.

When I took some resized cases that measured to the "0" mark on the RCBS precision Mic (1.630"), those same cases measured correctly with the old 400", 1 .611" and the newer .400" 1.622" insert. It now made sense to me.

All of these comparator type gauges don't read a true SAAMI measurement. I have a set of the Sinclair comparators and they are similar in not giving SAAMI measurements. What these gauges do very well is give you measurements off of your fired and resized cases and allow you to set your F/L sizing die precisely to where you want it.

When I was at my friend's shop, I took the Hornady and Sinclair sets and measured them to the proper inserts for 223, 308 and 30/06 Go gauges. I wrote down all of the measurements, just for reference.

Gauges like the RCBS Precision Mic and the Whidden case gauge give you SAAMI Minimum @ the "0" mark on the gauge. The older"Mo" gauge was the same.

When I first bought the Hornady gauge set, I had the incorrect assumption that I would be getting SAMMI corresponding numbers. I believe new users of these sets think the same thing and start scratching their heads when they get these numbers that are not making sense.

My reason for originally purchasing the Stoney Point (Hornady) set is because I reload for ten or so rifle calibers. This set covers just about every standard cartridge out there. The RCBS, Whidden and Mo gauges are great, but they cost about $50.00+ per caliber.

There was a you tube video on this subject made by a member here explaining this, but i can't find it.

Hope this help some of the members here that don't use these tool to understand how they measure.
 
You are not following how the Comp shellholders work. They are designed to allow the cases to be inserted farther in to the to die.

If you have a die that is too long you can:
  • Remove material off the die yourself or send in to the manufacturer with fired brass who will do it for you
  • Remove material off the shellholder
  • Buy the comp shellholder kit which reduces the size of the shellholder in .002 increments from the industry standard
As I mentioned, it's not a 1 in a million problem. It's surprisingly common. And Forster, RCBS and others do not offer custom shellholders. They have relied for years on customers being unable to measure if their product is working correctly.

The Redding Competition shell holders do not allow the cases to be inserted farther into the die. They move the case further out in increments of .002" to a total of .010". I use them often to adjust shoulder bump depending on the brass I'm using.

You can take the .010" and use it to make hard contact & camover on the die & shell holder and then use them incrementally down to size further to fit your rifle's chamber. I have one F/L die I set the +.006" to SAAMI minimum and then I can go up or down, but that's assuming you have enough room on your die to do that.

If you have a die that will not get to SAAMI minimum on a standard .125" shell holder, the Redding set won't help you. You will either have to face off the bottom of the die or sand down a shell holder.
 
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You are not following how the Comp shellholders work. They are designed to allow the cases to be inserted farther in to the to die.

If you have a die that is too long you can:
  • Remove material off the die yourself or send in to the manufacturer with fired brass who will do it for you
  • Remove material off the shellholder
  • Buy the comp shellholder kit which reduces the size of the shellholder in .002 increments from the industry standard
As I mentioned, it's not a 1 in a million problem. It's surprisingly common. And Forster, RCBS and others do not offer custom shellholders. They have relied for years on customers being unable to measure if their product is working correctly.
 

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If the Redding comp set won't address the issue of too long a die then I guess there are two options- reduce die or reduce shellholder.

I'll reach out to Erik to let Speedy know :)
 
If the Redding comp set won't address the issue of too long a die then I guess there are two options- reduce die or reduce shellholder.

I'll reach out to Erik to let Speedy know :)

THIS IS RESOLVED. I swear nobody reads each other’s posts. The competition shell holder kit not working has been beat to death.
 
Lol, so did you figure out what was the root cause? Small chamber?

Yes,Small chamber :) maybe a shell holder kit will fix this lol

The reason I mentioned that I have the kit in my OP I should have explained. If I had decided to take the .010 from the die then it would be married to this specific chamber and brass. I would need to use over sized holders with other brass for my other 6.5s
 
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I've had very good luck lapping the shellholder when I couldn't bump the shoulder enough; taped (Gorilla, of course), a 1/3 sheet of wet or dry paper to a piece of scrap polished granite (countertop cutoff). Put some water on the paper and run it over the paper in a figure eight pattern. Turn shellholder often and mic it until you have what you need. Keep shellholder separate from the others. No point to alter the die. I've taken more off than I needed, allowing feeler gauges inserted between shellholder and die for fine adjustments, in or out. This shouldn't take more than 30 minutes, maybe faster depending on how much you need to remove. Dirt cheap fix and FAST!
 
You didn't say what gun you're using, but if the go, no-go gauges work OK, your chamber is likely OK. Maybe casings are short to begin with; I see short cases regularly with Wolf and Lapua, new brass and loaded rounds, sometimes up to .004" short of SAAMI minimum. Wilson case gauge will tell you. Mike Bellm's T/C website sells a dial indicator adapter that will give you an instant read as to how long any case is relative to SAAMI max. and min.
 
I had the same problem with trying to use a dillon 223 sizing die on a lee press.

It is now a decapper on my app since I dont size on the dillon.
 
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You didn't say what gun you're using, but if the go, no-go gauges work OK, your chamber is likely OK. Maybe casings are short to begin with; I see short cases regularly with Wolf and Lapua, new brass and loaded rounds, sometimes up to .004" short of SAAMI minimum. Wilson case gauge will tell you. Mike Bellm's T/C website sells a dial indicator adapter that will give you an instant read as to how long any case is relative to SAAMI max. and min.
It is a Seekins Havak in 6.5 creed. Look at youtube user page 372HGS to see it in action.
 
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its not a long die.. You have not been reading. Its a short chamber issue and its resolved.
Your die is definitely long. If the chamber was .009 short, you wouldnt even be close to getting a virgin lapua case to chamber in the beginning. It’s all just a few thou shorter than a go gauge. Like .002-.003 short. Basically all virgin brass is that way.
 
Your die is definitely long. If the chamber was .009 short, you wouldnt even be close to getting a virgin lapua case to chamber in the beginning. It’s all just a few thou shorter than a go gauge. Like .002-.003 short. Basically all virgin brass is that way.
This is the 6th chamber that I have loaded for using this die. No issues with any of them. Just this Seekins Precision
 
Apologies for bumping an old thread, but I have an issue of similar topic. I just started reloading for my R700 6.5cm, and recently purchased the whidden .400 shoulder bump gauge. My numbers are .020" off of saami spec...I'm getting 1.525 for new Lapua/peterson brass, 1.528 for fired lapua/peterson brass, 1.525 for hornady new brass, 1.530 for fired hornady brass. I disassembled the bolt and am showing 1.5265-1.5270 for when the bolt handle will fall without resistance on FL sized brass. My assumption is my datum measurement is different than others as the brass is still fit to the chamber, but I'm a little confused as it's a new, quality gauge/comparator, yet my numbers are way off.
 
Apologies for bumping an old thread, but I have an issue of similar topic. I just started reloading for my R700 6.5cm, and recently purchased the whidden .400 shoulder bump gauge. My numbers are .020" off of saami spec...I'm getting 1.525 for new Lapua/peterson brass, 1.528 for fired lapua/peterson brass, 1.525 for hornady new brass, 1.530 for fired hornady brass. I disassembled the bolt and am showing 1.5265-1.5270 for when the bolt handle will fall without resistance on FL sized brass. My assumption is my datum measurement is different than others as the brass is still fit to the chamber, but I'm a little confused as it's a new, quality gauge/comparator, yet my numbers are way off.
Its not a gauge, its a comparator. Forget the saami spec. Your virgin and fired dimensions look about perfect to me.
 
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Its not a gauge, its a comparator. Forget the saami spec. Your virgin and fired dimensions look about perfect to me.
That was my initial thought, as I’d set the redding FL die and reloaded the first 50 rounds setting headspace with the tape method. It was just surprising to see the difference with the whidden gauge/comparator and the fact it was so far off the other measurements posted in this thread.

Would this just indicate that I have a chamber smaller than saami spec?
 
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If you have a chamber SMALLER than SAAMI spec, you wouldn't be able to chamber new, factory brass. STOP going off of SAMMI specs numbers on your comparator. You are using a comparator, not a gauge.

If you want to know the actual SAAMI spec on your comparator, you can use a "GO" headspace gauge and measure it on your comparator. That will give you the number. IT will be different than what is shown on the GO gauge.

On my Hornady comparator, a 308 Win. 1.630" GO gauge measures 1.611". So 1.611" for me is 1.630", a difference of .019"from the SAAMI spec. I have a friend who had the GO gauge and let me measure off of it.

Forget about the SAAMI spec number. Go off of what your comparator reads. There's really no "NEED" for you to know the SAAMI spec number. There is no NEED for you to go buy a GO gage.

Set your die to bump the shoulders of your fired cases to minus .001"-.002". Your comparator will work fine for you.

Most factory new cases will be anywhere from @ SAAMI min. to minus .001"-.004" or so.
 
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That was my initial thought, as I’d set the redding FL die and reloaded the first 50 rounds setting headspace with the tape method. It was just surprising to see the difference with the whidden gauge/comparator and the fact it was so far off the other measurements posted in this thread.

Would this just indicate that I have a chamber smaller than saami spec?
No, look at the difference between the virgin and fired cases. Consider the virgin cases must be smaller than a go gauge(so they fit any in spec chamber), and your chamber should be slightly large than a go gauge(so it will accommodate any in spec ammo), your numbers look about ideal. If your chamber was too small, the virgin cases wouldn't fit. If your chamber was too large, cases would be growing a ton. Neither of those things are happening.
 
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If you have a chamber SMALLER than SAAMI spec, you wouldn't be able to chamber new, factory brass. STOP going off of SAMMI specs numbers on your comparator. You are using a comparator, not a gauge.

If you want to know the actual SAAMI spec on your comparator, you can use a "GO" headspace gauge and measure it on your comparator. That will give you the number. IT will be different than what is shown on the GO gauge.

On my Hornady comparator, a 308 Win. 1.630" GO gauge measures 1.611". So 1.611" for me is 1.630", a difference of .019"from the SAAMI spec. I have a friend who had the GO gauge and let me measure off of it.

Forget about the SAAMI spec number. Go off of what your comparator reads. There's really no "NEED" for you to know the SAAMI spec number. There is no NEED for you to go buy a GO gage.

Set your die to bump the shoulders of your fired cases to minus .001"-.002". Your comparator will work fine for you.

Most factory new cases will be anywhere from @ SAAMI min. to minus .001"-.004" or so.

No, look at the difference between the virgin and fired cases. Consider the virgin cases must be smaller than a go gauge(so they fit any in spec chamber), and your chamber should be slightly large than a go gauge(so it will accommodate any in spec ammo), your numbers look about ideal. If your chamber was too small, the virgin cases wouldn't fit. If your chamber was too large, cases would be growing a ton. Neither of those things are happening.

Thanks guys, I knew I needed to go off fired brass and bump roughly .002", I guess I was just surprised by the comparator not being a gauge. I should probably get a go-gauge, but I'm just glad I have an accurate way to compare bump now.
 
I should probably get a go-gauge
You don't NEED a Go gauge for what you are doing. Get that out of your head.

Go, No Go and field headspace gauges are used to check the size of chambers of rifles and used when cutting a chamber.

From your measurement numbers of new brass and fired brass measurements, your rifle's chamber is fine.

Your comparator is doing it's job.
 
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So if you really want a maddening experience measure factory 223 and 5.56 ammo.
And then six or seven ar's.

Took a while but determined all our ar chambers are within 0.001

Started measuring fired 223 range brass. 95% of it matched our brass, but that other 5% wow what a mess.

I still wonder why all the slop in the specs but guess full auto 2 way range would be what set those standards and can't fault that.

It took the guys on the hide several weeks to beat the anal retentive German perfectionist out of me because I'm stubborn and for over 3 decades spec and precision oriented.