Reducing runout suggestion

[ODAVID]

I would like someone to explain if adding orings under the dies actually help. Do I have to reset the die length all over again . I think So??????

If Lee Collet neck dies are not available(7STW) are redding bushing dies a good substitute?? How do I select the correct bushing size????? Will the Wrong Size bushing create to much neck tension and create a Grenade effect????

And further. I would like experience suggestions on reducing and hopefully eliminating bullet runout cause by the tension created inside the neck from the "inside plunger" of the FL die. Can the "inside plunger" of the FL die just be removed after neck turning????? and eliminating the creation of runout??????????????????????????


I appreciate all suggestions based on actual experience

THANKS TO ALL
ODAVID

 

[kraky2]

This topic comes up so often I would really suggest that you do a search here and in other forums and you'll get tons of info.

First off you do have a runnout gauge correct? You won't get very far solving without it.

In my opinion o rings under the die do not solve the problem and yes any time you change the position of the die in the press you will have to re adjust it.

Neck turning can help reduce runnout and you may be able to get you to the point of not needing the sizing ball on the expander stem. At the very least it may eliminate alot of runnout even with the sizing ball in there because it will take less drag to pull the ball through.

FWIW I have found by fiddling with the sizing stem you can get it centered better on alot of FL dies and make really good runnout. Here is a copy of how I've done it:

One last trick if you want to "play a bit". Is to leave the spindle very snug but still loose enought you can turn it. Give the spindle small (Like 1/32 of a turn) turns and resize about 5 brass. If not concentric give another 1/32 turn. Keep doing this and eventually I find that I hit a "sweetspot" and the spindle is pretty much centered. I usually turn the spindle out of the die but of course you don't want to go so far the sizing ball bottoms on the case.
I've made HUGE improvements on alot of dies from all manufacturers by fiddling with the stem till it's centered. When you think that a piece of computer paper is .003" thick it's not hard to imagine a "non centered" ball/spindle could pull a case neck off center. Also, one last trick that helped with a Redding die was to use my finger to hold the shell casing at the back of the shellholder till it started into the die...that made a big diff for some unknown reason

 

[woods]

Hey ODAVID

If the Lee Collet is not available then you can send a fired case to Lee and they will make you one. The Lee Collet is simple to use and does do a fantastic job of reducing runout. It would be worth the wait.

However, if you want to try the Redding Bushing Dies, then I would recommend that you also have 2 other pieces of equipment. The first would be necessary in order to have a good way to measure the neck thickness. A ball micrometer and a stand

and the second would be a way to outside turn necks. I use the Forster hand held turner but there are others

The thing is that a bushing die will size the outside of the neck to the size of whatever bushing you buy. That will push all the variances in neck thickness to the inside of the neck. You could leave the expander ball stem in but you might as well use a regular full length die if you are going to size your necks with an expander ball (lot cheaper). The bushing type dies are at their best when used with no expander.

So if you are sizing the outside of the neck to a certain dimension and have a neck thickness variation of .002" from .013" to .015" (very common), then that variation will go to the inside of the neck and cause runout and varying bullet grip. Turn the necks for a consistant .013" overall thickness and you don't create runout.

To figure out what bushing size you need then measure your neck thickness and decide on the amount of bullet grip you want. For example if you turn your necks to .013" and want .003" bullet grip then

caliber+neck thickness one side+neck thickness other side-bullet grip=bushing size
.284"+.013"+.013"-.003"=.317"

Now some contend that the less bullet grip the better when it comes to runout. That is one of the premises of the Lee Collet which will only give .002" bullet grip (the mandrel is .002" smaller than caliber).

 

[dmproske]

I am having Lee make me a Collet die for my .300 RUM. They wanted two fired cases and a bullet. They said prolly 8-12 weeks.

I am also going around in circles with a Redding bushing neck sizer die. I start out with less then .001 neck runout from a fired case. After sizing with the bushing I get .002-.006 neck runout. Yes the expander ball is NOT in the die. I have tried several different bushing sizes, no difference.

I understand that the bushing will push the brass to the inside of the neck, so once you seat a bullet you have bullet runout. What I am talking about here is NECK runout right after sizing the neck and measuring B4 seating!! I would think I should have a straight outside neck at that point.


Once my neck turning tools get here I will outside turn the necks, then Lee Collet neck size. Then use the Redding body die when needed.

Once I turn my necks I will try the Redding bushing die again & give it one last shot. So far it has been a dissapointment. The redding comp seating die is a nice piece though.

 

[woods]

Hey dm

Good post. Very typical. I have a bushing die for my 30-06 that I gave up on. The bushing die for my 338RUM is doing fine though.

IMO you are headed in the right direction. Can't beat the combination of Lee Collet Neck Sizer, Redding Body Die and a Redding Competition Seater. I use one other and that is the Lee Factory Crimp. In my tests it slightly increases velocity and slightly decreases group size and takes worry away about getting low bullet grip from the Lee Collet Neck Sizer.

 

[boomtube]

The point of using an "O" ring under a lock ring is to allow the die to float into better alignment as the expander is withdrawn if the die or expander rod is off center. It can help IF the die/expander-stem/press misalignment is only slight. (It seems many reloaders think they should lock the dies in place with a wrench or pliers and that's not true, hand tight is plenty.)

I've read (no personal experience) that those using bushing type sizers are getting bent necks quite often. I use and love the Lee Collet Neck Sizers, NEVER get any added neck run-out with them!

Straight sized and expanded necks are the key to minimum run-out of loaded rounds. NO sizer or seater or seating method can correct for bad necks. I've found that attempts to seat better by going part way, turning the case 180 degrees and continuing, is futile. If a bullet starts crooked, it tends to STAY crooked! As described above, measure or turn your case necks to be sure they are straight and concentric; THEN a good seater can be your friend!

The Forster and Redding full length sleeve, "BR" type, seater dies are tied for being as good as it gets for use in a conventional press.

 

[Winchester 69]

After sizing with the bushing, I get 0.002 - 0.006 neck run-out.

Just covering a few bases:

Sizing more than 0.005" at a pass induces run-out.
The bushing should float (a little) in the die.
A little lube helps.
.

 

[BigJakeJ1s]

The O-ring can allow a die to float a bit in its threads for aligning with the case and shell holder.

However, for standard (i.e. not acme) threads, the conical/helical surfaces of the threads will cause the die to tilt as it floats horizontally in the threaded hole. The flat, load bearing surfaces of a Hornady LNL bushing, or of the Forster Co-Ax die slot, allow the die to float laterally without imparting a corresponding tilt.

Interestingly, the LNL bushing has an o-ring...

Andy

 

[Winchester 69]

I would like someone to explain if adding O-rings under the dies actually helps.

If you have a run-out gauge, it is simple enough to find out for yourself.

Glen Zediker introduced the concept, but he was replicating David Tubb's modification of the Dillon press. His use of the O-ring on the Lee Reloader Press may or may not correlate to your experience with your press. In other words, what kind of PreOsS are you using? Most people don't bother with it.
.

 

[bajabill]

Is the redding body die the only option to push the neck back without sizing the neck so the neck can be sized with only a lee collet die?


While FL sizing, how is the best way to lube the entire inside surface of the neck. Just lubing near the edge is not good enough, because when the expander ball passes thru while going in, it is not contacting the case surface much. But its the withdrawal that is needing the lubrication and and the first encounter with the neck is at the shoulder/neck junction. I think this is contributing to some of my case stretching I find while FL sizing 270wsm brass due to the large length of shoulder and somewhat tough brass.

 

[Michael Eichele]

The simplest way I have found is to use a FL die and first throw away the expander ball. Then I simply run a case into the die. This forms the whole case including the neck. Then, I measure the outside diameter of the neck. Then I seat a bullet and re measure the neck. From there I can see how much I need to turn off the neck to get the desired neck tension. Then I turn my necks. Then I just FL resize them and call it a day. When they come out of the die, the body and necks are perfect and it is done in one easy step.

I have my current set up set to .003" of neck tension and only had to take a couple of thousandths off the neck.

Simple easy and it works.

 

[Winchester 69]

The simplest way I have found is to use a FL die and first throw away the expander ball. Then I simply run a case into the die. This forms the whole case including the neck. Then, I measure the outside diameter of the neck. Then I seat a bullet and re-measure the neck. From there I can see how much I need to turn off the neck to get the desired neck tension. Then I turn my necks. Then, I just FL re-size them and call it a day. When they come out of the die, the body and necks are perfect, and it is done in one easy step.

Your method works for you, but the bushing die allows you to minimize the amount of brass shaved in order to allow accurate loads. Your method is determined by the thickness of the brass and the diameter of the sizing button. Your challenge is the mathematics. A larger sizing bushing permits you to remove less brass.
.

 

[Michael Eichele]

Your method works for you, but the bushing die allows you to minimize the amount of brass shaved in order to allow accurate loads. Your method is determined by the thickness of the brass and the diameter of the sizing button. Your challenge is the mathematics. A larger sizing bushing permits you to remove less brass.
.

I took about .002" of my necks. (.001 of wall thickness and .002 OD)

I dont know how much less you want to take off but .001 isnt much.

 

[davewilson]

i'm with meichele, a one piece FL die with no expander is the way to go. you size them and they come out perfect. i have a custom from Forster, which i've been told ruined it for everybody else, that makes my brass perfect every time.