GW Hunter
Well-Known Member
Missed the part on reducing the neck in more than one step. I don't neck size and I use the floating expander. Most of my cases come out <.002", a few don't. Maybe because of the one shot neck reduction?
neck clearances
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bigedp51
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The average reloader with a off the shelf factory rifle is better off with a full length resizing die like the Forster dies. Or use any type full length die with the expander removed and then use a expander die.
And I'm 68 and have been reloading over 47 years and do not own any custom chambered rifles. I also bought and tested the dies for neck runout after sizing to make my statements.
And Whidden sell expander kits with five expanders from bullet dimeter to .004 under bullet diameter. And I would assume these are for their non-bushing full length dies. And again Whidden does not make neck sizing dies.
I have had Remington cases with over .009 neck thickness variations and you can imagine what would happen with a bushing die and cases like this.
Bottom line, if you do not have factory cases with .002 or less neck thickness variations or have neck turned brass, you need a bushing die like you need another hole in your head.
Below Kevin Thomas and Eric Cortina of Team Lapua USA, and Kevin Thomas also worked in the Sierra balistic test lab and has far more experience than anyone in this forum.
Click on image to enlarge below, and read about the rat turd in the violin case. (meaning full length resizing)
And I'm 68 and have been reloading over 47 years and do not own any custom chambered rifles. I also bought and tested the dies for neck runout after sizing to make my statements.
And Whidden sell expander kits with five expanders from bullet dimeter to .004 under bullet diameter. And I would assume these are for their non-bushing full length dies. And again Whidden does not make neck sizing dies.
I have had Remington cases with over .009 neck thickness variations and you can imagine what would happen with a bushing die and cases like this.
Bottom line, if you do not have factory cases with .002 or less neck thickness variations or have neck turned brass, you need a bushing die like you need another hole in your head.
Below Kevin Thomas and Eric Cortina of Team Lapua USA, and Kevin Thomas also worked in the Sierra balistic test lab and has far more experience than anyone in this forum.
Click on image to enlarge below, and read about the rat turd in the violin case. (meaning full length resizing)
You very well could be showing neck thickness difference.
bigedp51
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They tell you to shake the bushing die to make sure it is a loose fit in the die and you can hear the bushing rattle. This means the bushing has enough side clearance to freely move side to side.
What can happen with a bushing die and reducing the neck dimeter .004 or more the case neck can force the bushing off center and even tilt.
To get the best results with bushing dies you should have a neck thickness gauge and a runout gauge. And you are better off with a tight neck chamber with neck turned brass to get the best results.
Tech Line & Tips (FAQs)
https://www.redding-reloading.com/tech-line-a-tips-faqs
Tech Line & Tips (FAQs)
Concentricity & Bushing Dies
From tests we have conducted, we have learned that selecting the correct bushing is the most important factor in producing sized case necks that have good concentricity with the case body. Our tests showed that case neck concentricity is directly proportional to bushing size. In other words, as you size case necks with progressively If the neck wall thickness varies more than 0.002", it may be necessary to use a bushing a couple of thousandths smaller than your calculations indicate, and then use a size button in the die to determine the final inside neck diameter.smaller bushings, the concentricity gets progressively worse.
Our current recommendation, is to select a bushing that is .001 to .002" smaller than the loaded cartridge neck diameter. For example, if the neck diameter of your loaded cartridges is .248", start with a .247 or .246" bushing. We've had to change our initial recommendation, because some of cartridge cases manufactured today have neck walls near the minimum SAAMI thickness. When using brass which is at the thinner end of the SAAMI spec. we have found the bushing which is .001" smaller will provide the best result.
To create precision reloads, you must start with cases of good quality. They should all be from the same manufacturer and lot number. A good measure of case quality is how uniform the neck wall thickness is. Cases with uniform neck wall thickness, will be of uniform thickness all the way to the base. This is important for accuracy, as the cases will expand uniformly upon firing, and contract uniformly when sized. Neck turning helps, but it's only a partial cure, as you can't turn the case wall all the way to the base. The Redding Case Neck Gauge is the preferred instrument for checking neck wall thickness and uniformity. Also note that the concentricity of a fired case only indicates how concentric your firearm's chamber is. It provides you with little or no information on the quality of the cases you're using.
Other factors that can improve concentricity:
- Lube case necks, even with TiN coated bushings.
- Partial size case necks. Sizing 1/2 or 3/4 of the neck seems to be the most popular.
- Try flipping the bushing over. We like to install them with the letters down to start with.
- Trim cases mouths square so they will enter the bushing straight. Don't forget to chamfer the case mouth, inside and out. This is very important as it eases the entry of the case mouth into the bushing, and the bullet into the case mouth.
- Anneal case necks. Cases that have been fired many times work harden and this causes excessive spring-back of the case necks.
Bushing Selection
The above methods of determining bushing size require that the cases being sized have a fairly uniform neck wall thickness or have been neck turned. If the neck wall thickness varies more than 0.002", it may be necessary to use a bushing a couple of thousandths smaller than your calculations indicate, and then use a size button in the die to determine the final inside neck diameter.
Tech Line & Tips (FAQs)
Concentricity Problems
Excessive difficulty while resizing can indicate any of the following: Poor choice of case lube, failing to clean the die and/or brass, faulty polish inside die, chamber large or at maximum S.A.A.M.I. spec resulting in excessive brass resizing. A large neck diameter in the chamber combined with brass that is thin or excessively turned can cause crooked necks in a hurry. The more brass has to be moved the more its residual memory takes over.
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It says what can happen is true but not that its gonna happen if you do. Like I said proper bushing die set up is the key.
I size down .006 all the time from .296 fired cases to .290 for a loaded .292.
.003"
GW Hunter
Well-Known Member
lol... here we go again...
Another plus to the honed Forsters is that it will size the entire neck; not just "most" of the neck like a bushing, which leaves a short section of neck at the shoulder unsized. This is an advantage if you are afraid of "donuts" in your brass, but donuts are not likely an issue in factory chamberings.
Varmint Hunter
Well-Known Member
The neck clearance you described is .006", IMO.
When I spec a neck clearance of .003" I get .0015" of expansion room on all (or both) sides. Typically, I like .003" of clearance in my hunting rifles. Some BR shooters use much less.
FWIW, I use Redding Type S FL bushing dies with TiN bushing and Imperial sizing wax with very low runout. Most of my brass is Lapua and I do turn neck for a few rifles but I hate doing it.
