die not sizing enough, options?

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Shadow9mm

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So I have a set of RCBS small base x-dies for 308. I also have a Hornady cartridge gauge with a min and max for the base of the casings. I have the press set so there is a moderately stiff cam over. However the casings are just barely passing max length. It is not hitting in the mouth area as I can see space between the mouth and the stop in the gauge. To me this mean it must be hitting the shoulder.

I find this odd as this is supposed to be a small base die set. As I am loading for my rifle and helping a couple friends with brass processing it is not practical to just make sure it works in mine

As I see it I have 2 options.

1 contact RCBS and see what they can tell me and possibly send it for warranty work. meaning my die set will be out of commission for a while.

2, modify the die myself. I was thinking sanding the mouth of the die maybe a thousandth or so so with some 800 grit wet dry, so it can resize the brass further. But it will probably void the warrant on my die set....

Of course I could be missing something, any other ideas?
 
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other ideas? hmm

does the sized brass chamber properly in the other rifles as well as your own? If yes, what's the issue?

is the shell holder "hard against the die bottom"??

IF yes, and brass is still not sized enough, consider working on the shell holder, not the die. Shell holders are cheap. Dies are not.

And contact the die maker, possibly the press maker, and ask their advice.

I am suspect of gauges reading "right" when made by someone other than the die maker. Everything has a range of tolerances, and I feel fairly confident that if made by the same company their tolerance range will be the same, but a gauge from another maker could be different enough to distort the reading. Not inaccurate as such, but possibly slightly different.

Ultimately, since you're not producing commercially to fit everything, the only gauge(s) that matter are the chambers they are going to be fired from. Check those, and see what results you get, before you go borrowing trouble you might not need to.
 
First question is this the used mg 308 brass you bought, or is it once fired from your rifle?
2nd question is what brand shell holder?
3rd question is there any space between the top of shell holder and bottom of die when the die is fully raised?

Am not understanding your wording on using the cartridge gage? What exactly are you measuring?
 
zeke said:
First question is this the used mg 308 brass you bought, or is it once fired from your rifle?
2nd question is what brand shell holder?
3rd question is there any space between the top of shell holder and bottom of die when the die is fully raised?

Am not understanding your wording on using the cartridge gage? What exactly are you measuring?
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Some is once fired. Some is out of my rifle and my friends. Same issue with both.

Shell holder is hornady. It's more of a plate as it is for my hornady progressive press. So working on the shell plate is not really an option. As getting them all the same would be difficult at best.

No space. Have medium cam over on the press. Its bottoming out on the shell plate firmly.

The gauge is a hornady loaded cartridge gauge. If the brass fits it should chamber. Has a min and max for headspace, which is where I am having problems. Barely at max, possibly a touch over. And a max for neck length, which if fine.
 
Hornady case gauges are not of the same quality as Wilson's in my experience, I only have a few of them if Wilson's were not available. I have a couple hornady ones that seem to be tight in the head area of the case so it's possible to get a false reading on case length. Simple test--any issues when dropping the brass into your rifle to see if it chambers freely? I noticed on RCBS's website it says x-dies have a special "growth inhibitor" mandrel which initially allows growth in the neck for the first couple of sizings; I wonder if your issue is something related to that?
 
The growth inhibitor only effects the neck length. You size normally with the mandrel up then trim. Next time you size 1 and lower the mandrel until it touches the sized case. Then size the rest. No more trimming. These were all sized without the mandril
 
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Sorry, missed that you were using x-dies and a progressive. The only 2 times i had anything resembling your apparent difficulty was when using another brands shell holder in a single stage press. Using a matching brand shell holder fixed it, as it did for several friends with same issue
 
I don't believe the Hornady press is a cam-over press. A cam-over press's ram goes past the top of the stroke and the ram starts back down again, as shown below. I think what you mean is just the die is bottoming out on the shell plate before the end of the stroke. On a cam-over press that happens at a much higher mechanical advantage, which is how some folks have broken their cam-over press castings. Most presses now have stops to limit handle movement before it reaches that higher mechanical advantage.

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What you want to do is first put a new piece of commercial brass in your gauge to see where it stops. You can cross-check with a case comparator or improvise one as shown below to check if the shoulder position is really coming up short. You can also color a case with Magic Marker and twist it in the gauge to see where it marks. In addition to a long head-to-shoulder dimension, have seen a few cases stall in a gauge at the rim rather than the shoulder because the rim was bent a bit by hard extraction.

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Ordered the LE Wilson head space gauge, will update when I get it and compare the 2 gauges. Hornady is a reputable brand, their gauge should be good. But I honeslty trust LE wilson better.
 
It seems you are doing what's needed to size your cases down . Not sure why firm contact on the shell plate does not size your case well below max on the gauge . However as stated above , If it chambers freely in the rifle/s it really doesn't matter how far it sits above the gauge . The progressive press does put me out of the loop , I use a single stage for bottle neck rifle cartridges so if it's the press I'd have no idea . The die being the issue is interesting to me , only because If you are extruding material towards the case mouth every time you size a case . How does the die stop the case growth , that extruded material needs to go somewhere ??? For lack of a better word/s , is it "back building" back into the neck and shoulder ?

FWIW my .002 shoulder bump of LC cases sticks above my Lyman gauge max and chambers in all 4 of my 308's .

Uc8HIt.jpg


For comparison this is a factory new Lapua case in the same gauge

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I am still a little confused why yours sticks out when sizing the case to what should be the dies maximum amount . That first pic above is sized using a #6 Redding comp shell holder , meaning the case is actually sized .006 longer then if I used a standard shell holder and firm contact . If I used a standard shell holder that case would be in the gauge at least as far as the new Lapua case is .

Here is L.E. Wilson explaining how to use there gauge .
https://www.youtube.com/watch?v=RuJYpm-qplQ&t=346s

I stopped using the case gauges when I bought my comparator . Get a few pieces of fired brass from each rifle . Use a comparator and see which fired brass is the shortest then bump all your shoulders -.002+ from that . All cases sized should chamber in all the rifles . Keeping in mind if any of the rifles fired case size is .006 or longer then the shortest rifles chamber . You will want to size for that rifle separately because that rifle will stretch the brass out more and you'll only be able to get about 1/4 to 1/2 the case life if you are shooting brass with a .006+ head clearance .
 
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IMO, those gages are designed more to tell you if your diameter is right than base to datum. A Hornady oal comparator or the Wilson is what I would use for base to datum.

Your Hornady gage may be dragging on an over sized base. Have you tried marksalot on the case and seeing what is touching? Or you could put 2 1mmx1mm bits of packaging tape on the shoulder and see if it measures that thickness further out of the case gage. Most of that stuff is 0.002” thick, but check it first.

Maybe the best tip is:
https://www.youtube.com/watch?v=htvk1UYOXm8

If you bump until your bolt handle drops without firing pin or ejector in it, that is what you are looking for.
 
Nathan said:
IMO, those gages are designed more to tell you if your diameter is right than base to datum. A Hornady oal comparator or the Wilson is what I would use for base to datum.

Your Hornady gage may be dragging on an over sized base. Have you tried marksalot on the case and seeing what is touching? Or you could put 2 1mmx1mm bits of packaging tape on the shoulder and see if it measures that thickness further out of the case gage. Most of that stuff is 0.002” thick, but check it first.

Maybe the best tip is:
https://www.youtube.com/watch?v=htvk1UYOXm8

If you bump until your bolt handle drops without firing pin or ejector in it, that is what you are looking for.
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No it is not what I am looking for. I am looking for factory speck brass. That is why I bought small base dies. I did this because this brass will be feeding more than 1 rifle, and not all are bolt guns.
 
All companies new brass ain't exactly the same size.

Send a few new cases to a custom die maker and he will make one for you.
 
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