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case sizing ?

Since the subject of one piece RCBS dies has been broached, let me make one suggestion, assuming unturned brass. Measure the OD of the neck of a case fired in your rifle at a specific distance from the shoulder where the shank of the bullet will be after seating. Size it normally with the expander ball in place and measure it in the same place. Seat a bullet and measure it again, in the same place. Finally, pull the bullet, remove the decapping assembly from the die size the case again, and do the same measurement. Based on my experience, what you will see is that the ID of the neck portion of the die is a lot smaller than necessary for unturned necks, by a lot. In the past I have used these dies as the basis for designing chamber reamers that were for turned necks. and which produced wonderful results. I chose a neck thickness that had the neck OD of the die working like a perfectly chosen bushing for benchrest, imparting just the right neck tension, and chamber body dimensions such that fired brass would be reduced in diameter only enough so that cases would chamber without resistance. Years ago, I did a little research and was told that RCBS one piece sizing dies are designed to produce body dimensions that are at SAAMI minimum for loaded ammunition. Lee dies are built to SAAMI maximum for loaded ammunition. These days, I generally avoid one piece sizing dies unless I am working with a custom chamber was designed for one, or it is a custom die. In both of those cases, one piece dies will generally produce slightly straighter brass than bushing dies, but the difference is not so great that it shows up on my targets.
 
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The only issue I have with Dies that utilize an expander ball system is that they don’t match my chamber very well and they work the neck of my brass like Grandma rolling out pie dough.

J
 
The only issue I have with Dies that utilize an expander ball system is that they don’t match my chamber very well and they work the neck of my brass like Grandma rolling out pie dough.

J

A honed forster die won't

And whidden makes an expander ball kit that lets you control neck tension very well. I have a whidden full length sizer with the expander ball kit. It makes very straight reloads with great control over neck tension. All the benefit of a bushing die without all the problems.
 
I get that honed die thing, good if you turn necks. Or keep the same brass
I just don’t have time to D..k around.
 
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Too Funny
Nah, Guffey hangs out on THR posting the same stuff.
J
 
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Since the subject of one piece RCBS dies has been broached, let me make one suggestion, assuming unturned brass. Measure the OD of the neck of a case fired in your rifle at a specific distance from the shoulder where the shank of the bullet will be after seating. Size it normally with the expander ball in place and measure it in the same place. Seat a bullet and measure it again, in the same place. Finally, pull the bullet, remove the decapping assembly from the die size the case again, and do the same measurement. Based on my experience, what you will see is that the ID of the neck portion of the die is a lot smaller than necessary for unturned necks, by a lot. In the past I have used these dies as the basis for designing chamber reamers that were for turned necks. and which produced wonderful results. I chose a neck thickness that had the neck OD of the die working like a perfectly chosen bushing for benchrest, imparting just the right neck tension, and chamber body dimensions such that fired brass would be reduced in diameter only enough so that cases would chamber without resistance. Years ago, I did a little research and was told that RCBS one piece sizing dies are designed to produce body dimensions that are at SAAMI minimum for loaded ammunition. Lee dies are built to SAAMI maximum for loaded ammunition. These days, I generally avoid one piece sizing dies unless I am working with a custom chamber was designed for one, or it is a custom die. In both of those cases, one piece dies will generally produce slightly straighter brass than bushing dies, but the difference is not so great that it shows up on my targets.

I absolutely agree with your last sentence and I have been at this a very long time also Boyd. Good info for progressing handloaders.
 
Hey Rebs how you doing ? I think cw308 is on to something . Load some of each and see what shoots better . I would ask what firearm or type of firearm you are loading for ? If semi auto I'd recommend you not neck size only . Semi auto's generally have less cam force when the lugs lock up and if you don't FL size your cases you can have feeding issues .

As for what is bumping the shoulder and FL sizing . IMHO FL sizing is when you use a standard size shell holder and have firm contact between the die and shell holder with cam over if applicable at the top of the stroke . That right there will FL size your case . Anything less then that is bumping the shoulder back to a specific location/distance . Now that might not be accurate or true but that's how I think of it .

FL sizing could also mean sizing the body the full length of the case . In theory one can FL size a case and actually not move the shoulder back or even actually move it forward some when using that definition .
 

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