308 ?'s - Page 2

F. Guffey · May 11, 2012, 07:34 AM

Bart B. said:
The case would have it’s shoulder set to 1.627 inch (+/- die tolerances of a few thousandths) from the case head plus another .002 inch. All of my .308 Win. dies will set fired case shoulders back past the SAAMI minimum case headspace (head to shoulder datum) when the die stops against a standard shell holder. There's no guarantee fired cases will be sized back to SAAMI spec minimum for case headspace.

Bart B. said":

Ignore my earlier post.

You mentioned:
Quote:
Case length is 2.005", I think.

Headspace is the distance between the case head and reference point on the case shoulder.

It's normal for a new .308 Win. case to shorten about 2 or 3 thouandths when its fired. It'll get longer by about that amount plus another thousandth when you full length size it.

--------------------------------------------------------------------------------

No, he did not say 2.005”, he said “i measured the once fired brass using a rcbs case mic. the headspace measured 2.161". SAAMI min is 2.160". when i full length resized, it was -0.006" under min”. Again, Where does the 2.161” come from, the case is 2.015” ( and + and – and you trim yours to .200”), then with out making sure Andrews understood the use of the RCBS micrometer, without making sure Andrews understands there is no measurement of 2.160 members of this board having him making adjustments in .001 thousandths increments. How is he expected to do that?? He claims he has a Redding three doe set, a set of Competition shell holders and, he said he got advise from a Redding Tech. and the Redding Tech. informed him he screwed the die down too far. And while talking to the TECH. Andrews failed to inform the TECH. he also had the 5 die set of shell holders, again, I do not use the competition shell holders, they are nice but not necessary, by choosing not to use the Redding shell holders I have 10 options between .000 and + .010 instead of 5.

“It's normal for a new .308 Win. case to shorten about 2 or 3 thouandths when its fired” Bart B., you spend too much time preaching to the choir, I doubt Andrews benefitted from from the information about “It’s normal etc., etc..” Again, he has a chamber, he has a case, the chamber has a length, the case has a length, the only length he needs to understand is the length of the case from the head of the case to it’s shoulder/datum and the length of the chamber from the bolt face to the shoulder/datum of the chamber. When fired the case does not shorten between the head of the case and it's shoulder, Andrews said he wants to start neck sizing. I believe he needs to practice, practice, practice and practice some more before he acquires more bad habits. And no, practice does not make perfect, and,. practice does not make perfect, he can practice it wrong and get it wrong every time, I believe he should practice it correctly. Then he can say correct practice makes perfect.

Your dies? You are familiar with the practice of grinding the bottom of dies and or shell holders, I am sure you have never heard me say it is not necessary, it is possible your dies came from someone that did not understand the incline plain, your dies were made for and or altered for sizing cases for short chambers, but if what Andrews said about the Redding reprehensive response is correct Andrews should send the dies back and ask for the instruction that should have come with the Competition shell holders.

Your dies: Notify the manufacturer of your dies and informed them you have measured your die’s ability to size a case and found them short. Or you can inform Andrews how you adjust them to obtain minimum length when full length sizing from the deck of the shell holder to the shoulder of the die.

F. Guffey

andrewst35 · May 11, 2012, 08:02 AM

yes i do admit, i measured WRONG but some dont seem to understand that and go on a rant and rave. i checked and the shoulder measured 1.161" using the RCBS case mic. i dont have alot of "fancy tools". i bought the Redding deluxe die set, rcbs case mic, and competition shell holder set. im not "stirring the ****", just asked for some simple advice. like i said, it was late at night and i listed the wrong measurement. some peaople make mistakes, others dont, which would be nice. i thought because of the measuremnet, i MAY have a tight headspace or may not. ill know more when i go to shoot my reloads and measure "twice fired brass". sorry for any misunderstandings. im human and make mistakes.

F. Guffey · May 11, 2012, 03:27 PM

Andrews, forgive, I knew when you posted the 2.161 number there was a mistake. The 2.161 number is .146 thousandths beyond the mouth of the case, I thought that should have been pointed out to you in the first or second second etc., response, but, as you can see it is not easy to soar when it appears there is at least three different conversations going on at the same time when the incorrect standard is being applied.

Discerning fact from fiction, truth from nonsense? I applied that criteria to Dmazur’s response, I did not find a pony.

I am the fan of determining the length of the chamber and the length of the case, it is something I find easy for me to do but I measure the length of the chamber three different ways without a head space gage, I measure the length of a case from the head of the case to it’s shoulder/datum with the humblest of tools. I do not find it necessary to fire a case to determine the length of the chamber, and I can not find a head space that will read head space in thousandths, I find head space gages skip too many numbers, for the 30/06 there are 3 head space gages, go, no and beyond, by being relaxed and not hard headed I have 14 head space gages from .000 to +.014.

Again, forgive,

F. Guffey

andrewst35 · May 12, 2012, 05:10 PM

Interesting.... just shot the rifle. 2nd fired brass measured 1.161-1.162", case mic measurement. Overall length didn't do too bad either, 2.005-2.007".

**Unclenick** · May 12, 2012, 06:26 PM

Something's amis with how you're reading it. I didn't comment before because I just assumed it was a graduation reading error, but that the difference would be correct.

Just to describe it:

Your Precision Mic came with a body with longitudinal graduations and male threads two thimbles (nuts, in RCBS-speak) with circumferential graduations and female threads and an ogive gauge that looks sort of like a cartridge.

Of the two thimbles, one has a small hole in the top for measuring to a bullet ogive. The other has a larger hole in top for measuring case shoulders at the headspace datum diameter. For the .308, that larger hole thimble should be stamped #4 at the knurling you grasp to turn it. To measure a case to its headspace datum diameter, you put the head of the case down into the body then place the thimble (nut) with the larger hole over it and screw it down so the case neck comes up through this hole. When you just feel this thimble touch the case shoulder (never force it), you look for a reading on the side where the circumferential scale on the thimble (thousandths) crosses the longitudinal scale (0.050" between graduations). When this reading is "0.000" on both scales, the length from the case head to where the inside of the hole is touching is nominally 1.630".

You can verify this by applying some Magic Marker to your case shoulder, then measuring it in the PM when it is dry. You should get a line in the dry Magic Marker ink where the gauge hole touched the shoulder. Use your caliper to measure from the case head to that line. You will see it is not very near 1.161" or 1.162", but rather is near 1.630".

andrewst35 · May 12, 2012, 07:45 PM

Yes I used the one with the larger hole and shorter of the two. It read 1 line above 0.

Bart B. · May 12, 2012, 08:21 PM

Unclenick's comments are excellent.

andrewst35 tells us:

Quote:

I used the one with the larger hole and shorter of the two. It read 1 line above 0.

I believe your case headspace would then be 1.631 inch. As new fired case headspace with the .308 are typically 1 to 2 thousandths shorter than chamber headspace, I'd guess your chamber's actual headspace is between 1.632 and 1.633 inch; right in the middle of SAAMI specs.

andrewst35 · May 12, 2012, 09:50 PM

Oh lord..... I must've really tired. Your are right. I misread the directions. It is 1.631". Lol. So what does it mean? Tight headspace or chamber or normal size?

andrewst35 · May 13, 2012, 10:50 AM

Would it be safe to trim my brass to 2.000"?

Bart B. · May 13, 2012, 02:41 PM

Andrew,

Yes, it's safe to trim your cases to an even 2.000 inch long. Folks have been doing that since 1963 when the .308 was first used in competion. That helped kick the old .30-06's but off the record score list in less than a year. Normally, with a case length of 2.015 inch in a standard SAAMI chamber, when the round's chambered there's still .010 inch clearance to the chamber mouth; SAAMI specs says the chamber is 2.025 inch from bolt face to chamber mouth. That allows for normal manufacturing tolerances for new cases as well as allowing room for the case mouth to move forward a few thousandths when the firing pin smacks the primer driving the case forward in the chamber setting the shoulder back pushing metal into the neck making it longer. When the round fires, the expanding case sucks brass back out of the neck, up the shoulder making the fired case a bit shorter than before. When full length sizing the case, it gets longer again.

Your rifle's chamber is very normal and safe and good. As I said before, as new fired case headspace with the .308 are typically 1 to 2 thousandths shorter than chamber headspace, I'd guess your chamber's actual headspace is between 1.632 and 1.633 inch; right in the middle of SAAMI specs of 1.630 to 1.634 inch.

Check out the "Reading" section in the following link as well as all of it, then learn about reading them and you'll soon be on your way to becoming a 3M guru; Master of Micrometer Measuring.

http://en.wikipedia.org/wiki/Micrometer#Inch_system

andrewst35 · May 13, 2012, 08:37 PM

So how does one maximize brass life to get the most reloads? When I got home, the brass length after shooting only grew 0.001"-0.002". How do I know when to start throwing away cases due to excessive reloads?

Bart B. · May 14, 2012, 01:35 PM

andrewst35 asks:

Quote:

So how does one maximize brass life to get the most reloads? When I got home, the brass length after shooting only grew 0.001"-0.002". How do I know when to start throwing away cases due to excessive reloads?

Set your full length sizing die in the press such that fired case shoulders are set back no more than .002 inch. If you can have your die's neck lapped out to a couple thousandths under a loaded round's neck diameter, you won't need to use the expander ball that opens up the case mouth diameter after sizing it way down. Or, use a Redding full bushing die with the right size bushing.

Are you referring to the case shoulder being .002 inch further out as measured by your case MIC? If so, that's very normal.

Some folks have got several dozen reloads on a single .308 Win. case using max loads, a full length sizing die with a bushing for the case neck and setting the fired case shoulder back 2 thousandths. An indicator that the case is getting too many reloads is a ridge will form inside the case just in front of the extractror groove. That can be felt with a wire hook put in the case and pushed back to feel the "notch" all the way around the case.

If there's someone in your neck of the woods that's reloaded a lot of ammo, contact him and he may help you out with these things. Such details with tools and cases is oft times difficult on internet forums to communicate as well as understand by readers.

May 12, 2012, 06:26 PM	#30
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,733	Something's amis with how you're reading it. I didn't comment before because I just assumed it was a graduation reading error, but that the difference would be correct. Just to describe it: Your Precision Mic came with a body with longitudinal graduations and male threads two thimbles (nuts, in RCBS-speak) with circumferential graduations and female threads and an ogive gauge that looks sort of like a cartridge. Of the two thimbles, one has a small hole in the top for measuring to a bullet ogive. The other has a larger hole in top for measuring case shoulders at the headspace datum diameter. For the .308, that larger hole thimble should be stamped #4 at the knurling you grasp to turn it. To measure a case to its headspace datum diameter, you put the head of the case down into the body then place the thimble (nut) with the larger hole over it and screw it down so the case neck comes up through this hole. When you just feel this thimble touch the case shoulder (never force it), you look for a reading on the side where the circumferential scale on the thimble (thousandths) crosses the longitudinal scale (0.050" between graduations). When this reading is "0.000" on both scales, the length from the case head to where the inside of the hole is touching is nominally 1.630". You can verify this by applying some Magic Marker to your case shoulder, then measuring it in the PM when it is dry. You should get a line in the dry Magic Marker ink where the gauge hole touched the shoulder. Use your caliper to measure from the case head to that line. You will see it is not very near 1.161" or 1.162", but rather is near 1.630". __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

May 13, 2012, 02:41 PM	#35
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	Andrew, Yes, it's safe to trim your cases to an even 2.000 inch long. Folks have been doing that since 1963 when the .308 was first used in competion. That helped kick the old .30-06's but off the record score list in less than a year. Normally, with a case length of 2.015 inch in a standard SAAMI chamber, when the round's chambered there's still .010 inch clearance to the chamber mouth; SAAMI specs says the chamber is 2.025 inch from bolt face to chamber mouth. That allows for normal manufacturing tolerances for new cases as well as allowing room for the case mouth to move forward a few thousandths when the firing pin smacks the primer driving the case forward in the chamber setting the shoulder back pushing metal into the neck making it longer. When the round fires, the expanding case sucks brass back out of the neck, up the shoulder making the fired case a bit shorter than before. When full length sizing the case, it gets longer again. Your rifle's chamber is very normal and safe and good. As I said before, as new fired case headspace with the .308 are typically 1 to 2 thousandths shorter than chamber headspace, I'd guess your chamber's actual headspace is between 1.632 and 1.633 inch; right in the middle of SAAMI specs of 1.630 to 1.634 inch. Check out the "Reading" section in the following link as well as all of it, then learn about reading them and you'll soon be on your way to becoming a 3M guru; Master of Micrometer Measuring. http://en.wikipedia.org/wiki/Micrometer#Inch_system Last edited by Bart B.; May 13, 2012 at 02:51 PM.

May 11, 2012, 07:34 AM	#26
F. Guffey Senior Member Join Date: July 18, 2008 Posts: 7,249	Bart B. said: The case would have it’s shoulder set to 1.627 inch (+/- die tolerances of a few thousandths) from the case head plus another .002 inch. All of my .308 Win. dies will set fired case shoulders back past the SAAMI minimum case headspace (head to shoulder datum) when the die stops against a standard shell holder. There's no guarantee fired cases will be sized back to SAAMI spec minimum for case headspace. Bart B. said": Ignore my earlier post. You mentioned: Quote: Case length is 2.005", I think. Headspace is the distance between the case head and reference point on the case shoulder. It's normal for a new .308 Win. case to shorten about 2 or 3 thouandths when its fired. It'll get longer by about that amount plus another thousandth when you full length size it. -------------------------------------------------------------------------------- No, he did not say 2.005”, he said “i measured the once fired brass using a rcbs case mic. the headspace measured 2.161". SAAMI min is 2.160". when i full length resized, it was -0.006" under min”. Again, Where does the 2.161” come from, the case is 2.015” ( and + and – and you trim yours to .200”), then with out making sure Andrews understood the use of the RCBS micrometer, without making sure Andrews understands there is no measurement of 2.160 members of this board having him making adjustments in .001 thousandths increments. How is he expected to do that?? He claims he has a Redding three doe set, a set of Competition shell holders and, he said he got advise from a Redding Tech. and the Redding Tech. informed him he screwed the die down too far. And while talking to the TECH. Andrews failed to inform the TECH. he also had the 5 die set of shell holders, again, I do not use the competition shell holders, they are nice but not necessary, by choosing not to use the Redding shell holders I have 10 options between .000 and + .010 instead of 5. “It's normal for a new .308 Win. case to shorten about 2 or 3 thouandths when its fired” Bart B., you spend too much time preaching to the choir, I doubt Andrews benefitted from from the information about “It’s normal etc., etc..” Again, he has a chamber, he has a case, the chamber has a length, the case has a length, the only length he needs to understand is the length of the case from the head of the case to it’s shoulder/datum and the length of the chamber from the bolt face to the shoulder/datum of the chamber. When fired the case does not shorten between the head of the case and it's shoulder, Andrews said he wants to start neck sizing. I believe he needs to practice, practice, practice and practice some more before he acquires more bad habits. And no, practice does not make perfect, and,. practice does not make perfect, he can practice it wrong and get it wrong every time, I believe he should practice it correctly. Then he can say correct practice makes perfect. Your dies? You are familiar with the practice of grinding the bottom of dies and or shell holders, I am sure you have never heard me say it is not necessary, it is possible your dies came from someone that did not understand the incline plain, your dies were made for and or altered for sizing cases for short chambers, but if what Andrews said about the Redding reprehensive response is correct Andrews should send the dies back and ask for the instruction that should have come with the Competition shell holders. Your dies: Notify the manufacturer of your dies and informed them you have measured your die’s ability to size a case and found them short. Or you can inform Andrews how you adjust them to obtain minimum length when full length sizing from the deck of the shell holder to the shoulder of the die. F. Guffey

May 11, 2012, 08:02 AM	#27
andrewst35 Member Join Date: May 6, 2012 Posts: 23	yes i do admit, i measured WRONG but some dont seem to understand that and go on a rant and rave. i checked and the shoulder measured 1.161" using the RCBS case mic. i dont have alot of "fancy tools". i bought the Redding deluxe die set, rcbs case mic, and competition shell holder set. im not "stirring the ****", just asked for some simple advice. like i said, it was late at night and i listed the wrong measurement. some peaople make mistakes, others dont, which would be nice. i thought because of the measuremnet, i MAY have a tight headspace or may not. ill know more when i go to shoot my reloads and measure "twice fired brass". sorry for any misunderstandings. im human and make mistakes.

May 11, 2012, 03:27 PM	#28
F. Guffey Senior Member Join Date: July 18, 2008 Posts: 7,249	Andrews, forgive, I knew when you posted the 2.161 number there was a mistake. The 2.161 number is .146 thousandths beyond the mouth of the case, I thought that should have been pointed out to you in the first or second second etc., response, but, as you can see it is not easy to soar when it appears there is at least three different conversations going on at the same time when the incorrect standard is being applied. Discerning fact from fiction, truth from nonsense? I applied that criteria to Dmazur’s response, I did not find a pony. I am the fan of determining the length of the chamber and the length of the case, it is something I find easy for me to do but I measure the length of the chamber three different ways without a head space gage, I measure the length of a case from the head of the case to it’s shoulder/datum with the humblest of tools. I do not find it necessary to fire a case to determine the length of the chamber, and I can not find a head space that will read head space in thousandths, I find head space gages skip too many numbers, for the 30/06 there are 3 head space gages, go, no and beyond, by being relaxed and not hard headed I have 14 head space gages from .000 to +.014. Again, forgive, F. Guffey

May 12, 2012, 05:10 PM	#29
andrewst35 Member Join Date: May 6, 2012 Posts: 23	Interesting.... just shot the rifle. 2nd fired brass measured 1.161-1.162", case mic measurement. Overall length didn't do too bad either, 2.005-2.007".

May 12, 2012, 07:45 PM	#31
andrewst35 Member Join Date: May 6, 2012 Posts: 23	Yes I used the one with the larger hole and shorter of the two. It read 1 line above 0.

May 12, 2012, 09:50 PM	#33
andrewst35 Member Join Date: May 6, 2012 Posts: 23	Oh lord..... I must've really tired. Your are right. I misread the directions. It is 1.631". Lol. So what does it mean? Tight headspace or chamber or normal size?

May 13, 2012, 10:50 AM	#34
andrewst35 Member Join Date: May 6, 2012 Posts: 23	Would it be safe to trim my brass to 2.000"?

May 13, 2012, 08:37 PM	#36
andrewst35 Member Join Date: May 6, 2012 Posts: 23	So how does one maximize brass life to get the most reloads? When I got home, the brass length after shooting only grew 0.001"-0.002". How do I know when to start throwing away cases due to excessive reloads?