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Discussion in 'Reloading' started by cabelas90, Mar 5, 2009.
What are the pros and cons of neck sizeing wothout an expander ball?
A pro would be to minimize the chance of having the expander ball cause case neck runout.
Not sure what exactly the cons would be for sure but I suspect inconsistent neck tension. I simply polish my expanders and allow them to float in the case by not tightening them to the die. Not sure if this is correct but it suits me fine.
On a standard sizing die you are actually sizing down the neck on the way in then pulling it over the appropriate size button for proper neck tension.
The only way to properly size without a button would be to have a bushing die or to have ordered a die with a specific neck diameter.
The benefit would be to have the neck perfectly true to the body not to mention concentric. This would only be true on a FL die with the proper neck size. Experience has shown me that a bushing neck die will not improve poor run out, though I'm not really sure why I though it would. A FL bushing die may but I have zero experience with that. At least this is what my impressions were as I'm still waiting on a die from Forester (they are only 9 weeks over their estimated delivery date).
Could you expand on this please? I'm curious as to your findings.
If you take a case with unacceptable neck run out and size with a bushing neck die the run out won't get any better. There is nothing to hold the body in place while the bushing sizes the neck to the proper size and location. The neck will be the proper size but will remain off center of the body. To much floating going on to straighten anything out, which is the way it was designed to work I believe.
As I have stated the FL bushing die may work but I'm not willing to spend the money on that when I could have a custom die made to my specific neck size.
I have also noticed brass with good run out wont get any worse when being run through a bushing die. It just never gets any better in my case though I'm sure some will disagree.
The only way to properly size a case without the expander, if in standard type dies, is to hone the neck portion of the die to be .0015"-.002" SMALLER than what the neck thickness is with a bullet SEATED in it.
Some dies will shrink the neck by .010", then the expander will bring it back up .008" to be .002" below bullet diameter. Without the expander or altering the neck section of the die, the case mouth may get damaged when you try to seat bullets.
A better method, and easier, is to polish the expander so that it is .0015"-.002" below bullet diameter. If it is the correct diameter to start with, just polish it with 1200 wet/dry, so it passes through the necks easier.
Another tip, use powdered graphite on a case neck brush, lube the inside of your case necks. Only a couple of passes into the neck are necessary, this will diminish any chance that the expander will gall on the way through the neck, and it won't over stress the necks or drag the shoulder forward. This also helps reduce split necks!
Keep the expander CLEAN, build up of CARBON is the biggest factor in the expander galling, remove the decapping stem after every use and wipe it clean with lighter fluid.
I use the polished expander method, when I'm not using bushing dies, and I have better neck tension with this method, unless you have custom neck dies the expander is still necessary to uniformity, because the neck die will resize varying neck thicknesses to varying diameters, and only the expander will make them uniform again in regards to neck tension.
I do not go into neck turning, unless it is absolutely necessary for the case to fit my rifle chamber, as long as the internal dimensions are the same, a few thou' difference in neck thickness won't alter accuracy enough to worry about, unless your shooting benchrest/1000yrd matches.
A concentricity gauge allows one to determine what things help and what things don't. Until you have one the old saying is true "ignorance is bliss" Once you get one you will start worrying and lose sleep.
"Once you get one you will start worrying and lose sleep. "
That's the truth! I didn't realize that I had a problem until I purchased one.
10-4 on that. often i wish i would have never bought one of the damn things. life was good before i started checking runout. it does make you feel good when a little extra time pays off and you start reading 0's and 1's though.
Sizing without the expander has a couple of major benefits: less runout, no lube in the neck.
IMO the best way to get rid of the expander is to use a Lee Collet Neck Sizer. That die has a floating mandrel that is .001" to .002" below caliber and it floats to center in your case neck and then you squeeze the collets onto the neck brass and size the brass to the mandrel. No lube necessary. In conjunction with a Redding Body Die to push the shoulder back and size the case body when necessary you will load very straight ammo and the Lee Collet are cheap.
Another way to get rid of the expander is with the various bushing type dies and pull out and discard the expander assembly that comes with them. If you are going to use the expander that comes with the bushing die then you might as well buy a FL die. The thing is that the bushing sizes the outside of the neck to a specific diameter. When it sizes the neck it will push all the variances in neck thickness to the inside of the neck. Typically brass will vary .002" or so, more in some cases and less in others. That .002" variance when transferred to the inside of the neck will push the bullet one way or the other and effect bullet release and create runout on the bullet. The way to get rid of this problem is to neck turn to a consistant neck thickness then the bushing dies will do very well and not create runout.
The last way I know of to get rid of the expander is to just take it out of your FL die. Most of the time this will create a little more bullet grip than you want. The amount of bullet grip will depend as much upon how thick your brass neck thickness is as it will depend upon the interior dimension of your die. Again if you neck turn then you can turn your necks to a specific thickness so that your FL die without the expander will size the neck to give exactly .002" to .003" bullet grip. However this may or may not be necessary. The only way to know is to:
1. Remove the expander
2. Size a neck
3. Measure the outside diameter (example on a 308 it might be .302" which means you have .308"-.302"=.006" bullet grip)
4. Seat a bullet
5. Measure the outside diameter again (in the 308 example it might be .336")
6. Subtract the loaded outside diameter from the caliber (.336"-.308"=.028")
7. Divide that number by 2 to get your neck thickness (.028"/2=.014")
8. Decide what bullet grip you want, let's say .002", then you need to turn the necks down a total of .004" or .002" each side, so turn the necks to .012"
Then with those cases with .012" necks all you have to do is shoot and size with the FL die sans expander and you will get .002" bullet grip.
If you don't want to neck turn then just get a Lee Collet and learn to use it and you will be happy.
Magman, i have a die something like the one you're talking about. Hehehe wanna borrow it?
after loading ammo with a die made for my gun, like Magman was talking about, i then tried loading ammo without the expander on a couple other guns. just take the expander rod assy out and reload your ammo. my guns shot every bit as good maybe better. try it, you might like it.
If you know what's good for you, you won't let that die out of your sight......but yes I'd like to barrow it.
I've tried it to and ended up with way to much neck tension. So much so I was wrinkling bullets or kinking necks when bullet seating. Maybe I was doing it wrong.
I'm sure by the end of the month I'll be on Forester's blacklist, so this may be my only die. Dave, can I use your name next time?
sure, go ahead and use my name. but my understanding is they have a picture of me on a dartboard up there!