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Old September 17, 2011, 09:10 AM   #26
F. Guffey
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http://lewilson.com/images/CASE_GAGE.pdf

"As matter of semantics for a technical activity in which the correct use of words matter; there is no such thing as a GO-NO GO gage for cases, those are made for chambers and are illustrated in post #7"

Reading and comprehension:

"A narrow, straight instrument, like a steel scale, will be of assistance in checking cone-to-head length"

Wilson calls the straight edge "a narrow, straight instrument, like a steel scale", to avoid the appearance of showing off, I refer to it as a straight edge, any straight edge and the set up table is one big flat straight edge, to take all the guesstimates like fingernails etc., I suggest using a feeler gage AND! a straight edge.

Again, for those of you that have a go-gage and the Wilson case gage the accuracy of the gage can be determined with a standard (think!) if both gages agree, both are standards.

"cone-to-head length" they did not say DATUM, they did not say SHOULDER, they said CONE, both Wilson and myself understand the CONE, "correct use of words matter" Reading and comprehension makes that possible.

There are those that can only use the gage as a "drop in gage" then there are those that read and understand "what it is they read", then there the few that see the chamber after the bolt closes and all the light is shut out. The standard, the transfer, the feeler gage is the most versatile tool I have, for some it could be too complex, to others it could be too archaic, Me? I can not see over my tools because the wall is 3' foot away.

http://lewilson.com/resources.html

The dial caliper: Think of it as a combination feeler gage/straight edge depth micrometer/debth micrometer, or use the Wilson case gage as a drop in gage.

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Old September 18, 2011, 10:25 AM   #27
Ike666
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I'm using some Lapua brass in my Remmy 700 PSS (.308), and I neck size the brass. It is on it's third cycle, so probably has quite a bit of case life left.

After following this discussion with great interest I decided to check it out in the lab (loading room). Using an RCBS case micrometer to check case length to the datum, I first ran it on a set of Forster chamber gauges.

GO: 0.000
NOGO: 0.004
FIELD: 0.0075

Then I checked the neck-sized brass, first in a Dillon headspace/case length gauge: all well within limits. Then I took a random 20% selection (10 cases) of the brass I had re-sized and checked them in the RCBS micrometer. The average (actually all except 1) gauged at 0.004 (same as NOGO chamber gauge).

Now, I knew the chamber in the Remington was getting long in the tooth, but it still checks within sammy [sic] specs. To seat a bullet 0.018 off the lands I'd have a COL of more that 3 inches. However, the rifle is still an absolute tack driver that will print .5 MOA groups as long as I do my part.

I also ran the case necks on the run-out gauge and the highest run-out was less than 0.001. The neck sizing was done on a Lee Collet die, and I've had really good experiences with it.

I'm not sure what all this means, except I'm going to have to watch the chamber/barrel on the Remmy.
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Old September 21, 2011, 06:55 AM   #28
F. Guffey
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Ike,

"GO: 0.000
NOGO: 0.004
FIELD: 0.0075

Then I checked the neck-sized brass, first in a Dillon head space/case length gage: all well within limits. Then I took a random 20% selection (10 cases) of the brass I had re-sized and checked them in the RCBS micrometer. The average (actually all except 1) gaged at 0.004 (same as NO-GO chamber gage"

There are others on this forum that own this topic, we (you and I) with different numbers could come up with the same answer with the same meaning, with the decimal point in the same place but only differ in where we start.

You have the chamber at .000, no-go at .004 and field at .0075, I start with the length of the case being full length sized or new and at minimum length, iso-iso. I index the length of the case at .000, this allows me to form cases for short chambers starting at -.0012 shorter than a minimum length/full length sized case, or .016 thousands shorter than a go-gage length chamber (for the 308 W), that would put the no-go length at .008 and field at .0115.

"The average (actually all except 1) gaged at 0.004 (same as NO-GO chamber gage)"

When using .000 for an index your chamber is .008 thousands longer than a minimum length/full length sized case from the head of the case to the shoulder of the case. If I was sizing cases cases for that chamber I would adjust the die off the shell holder .006 thousands, I would make the adjustment with a feeler gage, AGAIN, I have an Eddystone M1917, it has .016 thousands head space, when sizing cases for that chamber I adjust the die off the shell shell holder .014 thousands, in the beginning I used 280 Remington cases to determine the length of the chamber by forming cases that were progressively sized shorter and shorter until a case chambered, then verified the measurements with a feeler gage.

Methods and techniques, I make tools and gages, no matter what the gage indicates I am left with sizing cases with the press, did and shell holder, I take one measurement from the chamber, then transfer that measurement to the press, size a case and take it back to the chamber, a reloader can put $500.00 dollars in tools between the chamber and press and between the press back to the chamber, still the reloader is left with the press, die and shell holder to do the work.

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Old September 21, 2011, 03:09 PM   #29
Ike666
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Mr. Guffey

To make sure I'm understanding you on this: I'd back off the FL sizing die the thickness of the .006" leaf on a feeler gauge? This would set the shoulder for the chamber based on the dimensions of the fireformed cases, is that right?

I'm going to fire some LC brass in that rifle this week and experiment with that. I'll neck-size some and FL size some with the die backed out by .006" and then compare the results in the RCBS micrometer. I'll also drop test each in the rifle chamber.

I still like the results I get from the neck-sizing, but I also like to explore/develop all my options.

Thanks for your guidance.
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Old September 22, 2011, 10:38 AM   #30
F. Guffey
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"I still like the results I get from the neck-sizing, but I also like to explore/develop all my options"

For me it is easier to explain why I choose other options, years ago I decided to chamber a rifle, the advise I received led me to believe the information I was getting was coming from smith that did not have a clue, so before I chambered my first rifle I determined head space could be checked at least three ways without a head space gage. The first barrel I purchased was short chambered, how much? .250 thousands short, and we had words, short chamber could mean .015 thousands short, a new reamer can chamber 20+ barrels, chambering a .250 thousands short chamber to go-gage length is the equivalent chambering 16 .015+ short chambers, and they ask me how did I know the chamber was too short.

Yes, do not forget there is an old saying that is repeated over and over etc., 'fire to from, then neck size 5 times then full length size to start over', I do not know how they do that, that case has been fired 6 times meaning any technique or method is out the window when predicting the results when sizing.

'fire to from' I form first, in the process of forming a case that will chamber I have determined the length of the chamber. With a gage/comparator or a feeler gage I can determine the length of the case and or measure the gap between the bottom of the die and top of the shell holder, but, I can not accomplish this with cases that are work hardened and have resistance to sizing (cases that have memory, recovery, spring back or jump back). There is a time when I have to give up on a case, annealing is an option, because time is a factor and heat travels, I make my own annealing tool(s).

As to your answer and using the length of the case as .000 and go-gage as .004, I do not know what press you using, the ability of a press to size a particular case can be determined with a feeler gage, after raising the ram measure the gap between the bottom of the die and top of the shell holder, if the gap between the die and shell holder is still .006 and the slack has been removed between the threads of the die and press and if the die is secured to the press the case should be minimum length + .006 thousands. If the case chambers with resistance to bolt closing reduce the gap to .004. again I start with new/unfired cases.

I am not a fan of bolt closing with resistance, I am not interested in changing the tools you use, I have trim/forming dies, never regret the investment over other options, the 308 W is the versatile trim/forming die, with a feeler gage and standard blocks I can form most cases that are longer than the 308 W. case, I adjust the gap between the shell holder and bottom of the die based on information from case drawings/specifications.

Case diameter, measuring case diameter is possible, the most expensive method is the bladed micrometer, I do not have one, but then I do not find it necessary.

F. Guffey

Last edited by F. Guffey; September 23, 2011 at 10:49 AM.
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