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Old February 22, 2013, 12:31 PM   #26
F. Guffey
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Yesterday, 12:32 PM #20
Wyoredman
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Posts: 884 Guffey,

Here is how I used my Hornady "comparator":

Measured unfired, new factory case in the "comparator" installed on my caliper.

Measured fired case the same way. Fired case is 0.003" longer to shoulder datum than it was before firing.

Screwed FL die into press until it touched fired case, then began adjusting die down and measuring case length to shoulder datum with "comparator" until the case was 0.002" shorter. Set lock ring on die at this point.

My question to you, as you seem to know these things, is how do I make a "chamber length gage"? Please be specific so as I can benefit from your knowledge. If I lived nearby, I would bring the rifle to you and you could explain it to me, but no such luck.

Also, this still hasn't answered my original question about why this individual rifle is doing this to my brass! Are you suggesting that my chamber is oversized? I am a simple man and need simple, straight forward answers. Thanks.
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Wyoredman, Thank you, “My question to you, as you seem to know these things, is how do I make a "chamber length gage"? Please be specific so as I can benefit from your knowledge. If I lived nearby, I would bring the rifle to you and you could explain it to me, but no such luck” Long before I had barrels chambered in 35 Whelen and or 338/06 I had the dies. Long before I had store bought cases like 8mm57, 7mm57, 7.7 Japanese, 6.5 257 Roberts etc. I had 30/06 cases and invested in forming dies. Today that is an expensive alternative, I could justify the expense because I paid .01 cent each for 30/06 cases, 20 cases for $1.00, and the more expensive pull down unfired cases from Pat’s for .07 cents each.


Yesterday, 10:40 AM #16
603Country
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Join Date: January 6, 2011
Location: Thornton, Texas
Posts: 1,553 Since I don't have any 6mm Navy brass, I'm not able to form cases as FGuffey apparently does. I'm limited to fire forming and either neck sizing or partial resizing from there. In that specific rifle (my 220), I bought a neck die, but found over time that I got better accuracy with partial resizing, which works well with tapered cases.

Over 30 years with that rifle and two barrels and no case head separations. I assume that it boils down to the fact that I don't FL resize and set the shoulder back too far.

As for Wyoredman's question, if he's cut into cases and found no sign of case wall thinning at the base, I'd put it down to a little first firing case stretch. Tapered cases do tend to do that, which is why PO Ackley (as FGuffey mentioned) was always 'improving' cases and cartriges by reducing case body taper. Just neck size em from here and you should be fine, though occasionally, if you shoot em hot, you'll need to push that shoulder back a bit.




“Since I don't have any 6mm Navy brass, I'm not able to form cases as FGuffey apparently does” Again, I am a case former, I form cases, I do not form, load and shoot everything I form, more times than not I form to determine the length of the chamber from the bolt face to the shoulder/datum of the chamber, seems that part is ‘the mystery’, I am the fan of standards, transfers and verifying. Case formers are familiar with methods and or techniques for necking up cases ( Long before I had barrels chambered in 35 Whelen and or 338/06 I had the dies ) to establish a shoulder ahead of the shoulder on the case. If I was struggling with the length of the chamber from the shoulder back to the bolt face I would neck 10 220 Swift cases to .243/6mm or 6.5/264 (I would not choose 5 time fired cases). Agter necking the cases necks up I would then start sizing the necks down to create s shoulder, I would adjust the die off the shell holder .010” with a feeler gage leaf that was .010” thick, I would then secure the die to the press with the lock ring without allowing the die to turn. after forming the secondary shoulder I check the distance from the new shoulder to the head of the case with a home made datum to head of the case tool or a comparator.

if after establishing the ‘new shoulder’ the case does not chamber I would decrease the gap between the bottom of the die and shell holder, a good choice would be .007”, I would repeat the process until a case chambered. this method and or technique does not work for reloadrs that insist on using 5 time fired cases, like braking fingernails, they do not handle case neck splits very well.

What to do with the gap number as in the die off the shell holder on thousandths, contact Redding, order a shell holder or set or use the feeler gage to make the adjustment, start with new cases, I would, after firing apply the ‘leaver policy’.

I know, bench resters do it this way and or the other way, then there is the full length sizing every time crowd, then there is the bullet manufacturing methods and techniques, when duplicating their methods and techniques remove the stock on your rifle and clamp the barrel in a vise, leave the receiver just ‘hanging out’.

F. Guffey
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Old February 22, 2013, 12:40 PM   #27
F. Guffey
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Wyoredman, I have a machine that is designed to make pilots, tapped pins, and angles, something like an in-line, angle and butt grinder, easier to use than the add-on tool post grinder. Not a problem but a gage that is a fixed length has one length, then there is the modifying of a fixed length gage. Advantage? The advantage goes to the short length gage, again my favorite forming die is the 308 W.

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Old February 22, 2013, 01:16 PM   #28
603Country
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Guffey, I must be missing something. Firing the case in your rifle chamber will give you pretty much an exact shoulder that fits your rifle chamber. What's the great joy and process improvement from your pre-making a shoulder on a case that will then be fired in your rifle and give you exactly the shoulder you'd have gotten if you fireformed it in the first place. Can you give me the short answer on that? I'm not obsessive enough to use your approach, but I would like to understand it.
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Old February 23, 2013, 09:22 AM   #29
F. Guffey
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Yesterday, 09:40 AM #16
603Country
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Join Date: January 6, 2011
Location: Thornton, Texas
Posts: 1,555 Since I don't have any 6mm Navy brass, I'm not able to form cases as FGuffey apparently does. I'm limited to fire forming and either neck sizing or partial resizing from there. In that specific rifle (my 220), I bought a neck die, but found over time that I got better accuracy with partial resizing, which works well with tapered cases.

Over 30 years with that rifle and two barrels and no case head separations. I assume that it boils down to the fact that I don't FL resize and set the shoulder back too far.

As for Wyoredman's question, if he's cut into cases and found no sign of case wall thinning at the base, I'd put it down to a little first firing case stretch. Tapered cases do tend to do that, which is why PO Ackley (as FGuffey mentioned) was always 'improving' cases and cartriges by reducing case body taper. Just neck size em from here and you should be fine, though occasionally, if you shoot em hot, you'll need to push that shoulder back a bit.

Today, 01:16 PM #28
603Country
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Join Date: January 6, 2011
Location: Thornton, Texas
Posts: 1,555 Guffey, I must be missing something. Firing the case in your rifle chamber will give you pretty much an exact shoulder that fits your rifle chamber. What's the great joy and process improvement from your pre-making a shoulder on a case that will then be fired in your rifle and give you exactly the shoulder you'd have gotten if you fireformed it in the first place. Can you give me the short answer on that? I'm not obsessive enough to use your approach, but I would like to understand it.


“Since I don't have any 6mm Navy brass, I'm not able to form cases as FGuffey apparently does” 603Country, you started out missing something, now you are ahead, it is not necessary for a reloader to go back to the beginning and start over.

Do I think you are missing something, no, I believe you skipped a few chapters, there is nothing in my response a reloader should not know, added to the chapters you skipped, this is not the reloading forum.
What is the joy?? I will ask you, what satisfaction do you get out of doing it correctly? The difference in what joy is the difference between knowing what you are doing and ignorance. (Ignorance as in not knowing)

The difference in length between the 30 Gibbs and 30/06 from the head of the case to the shoulder of the case is .112”. 30/06 cases are fire formed to 30 Gibbs, I know of no one that chambers a 30/06 round in a 30 Gibbs chamber and then pulls the trigger. I could increase the chance it would work but I increase the chance of success by necking up the 30/06 to 338 or 35 cal. first then establish a secondary shoulder to head space on (as in .000 difference in length between the chamber and case, remember I am a reloader with a press and dies with threads, threads make it possible to adjust, JOY? I take pride in what I do, I get satisfaction from getting it correct. I eliminate case travel, when forming 30 Gibbs from 30/06 the case shortens .035” in length.

My favorite cases are a cases that has been shot in a trashy old chamber or 280 Remington cases, the 280 case is longer from the head of the case to the case body/shoulder juncture than the 30/06 by .051” and the 280 case is .041 longer, meaning? I do not have to settle for short 30 Gibbs cases. The perception that chambering a round and pulling the trigger is fire forming is a more like a bad habit than an answer or cure. Back to the part where I said I want to know the length of the chamber first. Necking a case up then sizing the neck to establish a second shoulder eliminates case travel, the 220 Swift is prevented from moving forward by the rim, no one knows how far the shoulder of the chamber is from the shoulder of the case when the trigger is pulled, no. A reloader that understand the length of the case can be increased between the head of the case to the shoulder can eliminate case travel by head spacing on the shoulder of the chamber.

Not available, cases with thicker rims or thicker belts, in the world of reloading knurling to raise a surface does not exist, out side of the world of the 303 British case no one measures the thickness of the rim.

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Old February 23, 2013, 05:11 PM   #30
603Country
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That wasn't the short answer, or at least I hope it wasn't, but you are doing what I suspected. You are eliminating the small amount of case stretch by making the secondary shoulder. And I can see that if you don't know how long a chamber is, your approach is technically better. On the other hand, Wyoredman's chamber is a known quantity and fireforming a case in his chamber (or mine) shouldn't be that risky a business and quite honestly should not need the extremes that you suggest. If, however, you are changing calibers and it isn't something simple, like 223 to 223AI, your approach is understandable.

And now I do understand what you were saying. Thanks.
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Old February 25, 2013, 11:00 AM   #31
F. Guffey
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February 23, 2013, 06:11 PM #30
603Country
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Join Date: January 6, 2011
Location: Thornton, Texas
Posts: 1,559 That wasn't the short answer, or at least I hope it wasn't, but you are doing what I suspected. You are eliminating the small amount of case stretch by making the secondary shoulder. And I can see that if you don't know how long a chamber is, your approach is technically better. On the other hand, Wyoredman's chamber is a known quantity and fire forming a case in his chamber (or mine) shouldn't be that risky a business and quite honestly should not need the extremes that you suggest. If, however, you are changing calibers and it isn't something simple, like 223 to 223AI, your approach is understandable.

And now I do understand what you were saying. Thanks.



“Wyoredman's chamber is a known quantity and fire forming a case in his chamber (or mine) shouldn't be that risky a business and quite honestly should not need the extremes that you suggest”

You are assuming Wyoredman’s chamber is a know value, he did ask how and could the length of the chamber be checked, not my job to place limits on someone’s ability, not my job to help him spend money on equipment that would be nice but not necessary. again, I have threads on my presses, I have threads on my dies, threads on my presses and dies make make it possible to adjust the length of the case from the shoulder of the case back to the head of the case, with the most humble of tools, the feeler gage.

In 10 words or less? if you have your mind made up it can not be done, you can not do ‘it’. Long before us it was done, difference? Back then they did not talk ‘it’ to death.



“And I can see that if you don't know how long a chamber is....” ‘You’? Again, for me, there is no such thing as not knowing the length of the chamber from the shoulder of the chamber to the bolt face.

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Old February 28, 2013, 10:29 AM   #32
Nevmavrick
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After you've shot the case, there is no reason to move the shoulder back...until it's so tight in the chamber that you can't rechamber the unsized case.
If you keep moving it back and firing it forward, you WILL get a seperation. The case needs to be headspaced on the shoulder. I headspace all my ammo on the shoulder, even my .357 Herrett, .30/30 Win, and .30/40 Krag!
Reading gages is fun, for some, but unnecessary. just resize the case to just short of all the way down the neck. You only NEED the neck sized to where the bottom of the bullet is. The rest of the neck has been fireformed to the size of the chamber, therefore will help align the case with the chamber/bore, and should be more accurate.
I'm not sure from the picture if you've cleaned the case after shooting it before you reloaded it the rest of the times. (referring to the case that's been reloaded 4 times.) So, is that the same ring...or does it put a new ring on every time it's fired?
I suspect that there is a tight spot in the chamber, but it doesn't matter. After you've fireformed the case it won't move. From that ring back, the case isn't supported. So what? That's the solid part of the case, anyway.
Since the gun is so old, you're off warranty, you might have the barrel turned back then rechambered, or even rechambered for an AI.
Better yet...PM ME. We'll discuss my buying it, and what I will do to it!!!
Have fun,
Gene
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