?Best brass runout from bushings die.

[rvander1]

Hi Guys,
I reload 6.5-284 Lapua brass, and I resize the brass with a Redding FL Bushing die and get 80% with a neck runout of +/- .001, and the other 20 % has neck runout of +/- .003. Seated bullet runout is about the same.
These loads are for a custom 1000yd gun (the reason for trying to reduce runout).
I'd like to get less runout--
All advice appreciated!
Bob

 

[lmorrison17]

Get a no bushing die. This subject has been bet to death, there is a multitude causes and remedies. Do a search here and over on BR Central and you'll have plenty of reading and ideas of what chase first. Here is a start.

http://forum.accurateshooter.com/index.php/topic,3744568.msg35847158.html#msg35847158

http://forum.accurateshooter.com/index.php/topic,3753492.msg35892599.html#msg35892599

 

[pmarauder]

How much are you sizing them down? what dimension is your chamber vs your bushing?
What i found to help get consistant low run out and also neck tension is to FL size just enough to bump the shoulder back .0015. Then i will run them through a expander die to iron out the inside of the neck. Then i finish them with a NS bushing die to only size about 70% down the neck. This will get me my final neck dimension/tension.
works good for me

 

[halfmoanut]

Don't rule out the bullet seater. Also try another bushing they are all not created equal.However with a custom made die by the guy who chambered the rifle can't be beat except for the price.You can check runout after each step with each die and see where the problem is it may be in your turned necks or any combination of the three.

 

[rvander1]

Thanks for the help.
My chamber neck is296, and I'm using a .292 Redding Bushing.
Haven't tried a different bushing- I think I may call Redding to see if they'll send me another bushing (its the more expensive gold one.)
Halfmoanut- I called my gunsmith and a custom die from him would cost me almost $400 since he doesn't have the die reamer for my chamber.
I called Harrell but they don't make custom dies for 6.5-284. I was surprised to find out that their custom dies (actually semi custom), are bushing dies--so maybe I'm wrong but the Harrell custom dies must produce pretty concentric ammo since they make the custom dies for the 6ppc and 6br boys who demand and need near perfect concentricity to be competitive.
I've tried two different presses, and even different shell holders.
Getting ready to call Neil Jones and pay the big bucks out of frustration.
I also ordered a non bushing die today from Hornady--suspect that will work the best.
All advice appreciated.

 

[mikecr]

Didn't see where you turned your necks. Have you measured at the necks with a ball mic & culled cases by thickness variance?

The more you size, the more this becomes a factor.
The method(use of bushing) is NOT a root cause of runout. Never has been..

 

[butchlambert]

How serious are you?
Butch

 

[BoydAllen]

Run a case neck mic. around a steel or coated bushing, and then do the same thing on a carbide bushing. I understand that carbide bushings are ground, and when I switched my numbers got better.


Speed costs money. How fast do you want to go?

 

[butchlambert]

I may have some solid carbide 6.5 bushings left. Sizes are very limited.
Butch

 

[rvander1]

mikecr:
I have turned the necks to just under 15 thou which eliminates about 90% of the variance in new Lapua.
I am measuring the necks with a Sinclair Case Neck Micrometer. However since my runout problem is with brass- not loaded round measuring on the bullet-- I guess I don't see how a small amount of wall thickness variation matters for brass concentricity although I understand how it would for the loaded round runout measuremeent, but maybe I'm wrong on this.
I'm measuring my brass concentricity on a Sinclair Concentricity gauge, with the brass support on the gauge on the body just behind the shoulder/body junction, and the dial indicator in the center of the sized portion of the neck (I only size about 70-80% of the neck). I'm using a Rockchucker Press which is tight-- and some have advised getting a Hornady Co Ax so the die will float-- but I don't know how important this might be-- your input would be appreciated on this. Runout of brass fired in my .296 chamber is zero.

BoydAllen,
First, thanks for your expertise.
I don't have any carbide bushings-- since I bought the die from Redding and bought their Titanium Nitride Coated steel bushings. I measured the bushing and the bushing wall thickness varies by .001!!! it measures .105 on one side and gradually increasaes to .106 on the other side-- seems to me the bushing hole was not drilled in the exact center of the bushing?? --How about the rest of the die-- maybe the hole where the bushing sits in is off center??

Thanks again to all of you-- I may get a straight cartridge yet!
Bob

 

[butchlambert]

Bob,
The only thing that matters is if the hole is truly round and is perpendicular to the base of the bushing. If you let your bushing float it won't matter.
Butch

 

[BoydAllen]

Verifying the perpendicularity of the hole through a bushing, to its faces, is well beyond my in house capability, but measuring sized brass is not. Mine came out straighter with carbide. I suppose another good question would be does the difference matter? I don't know. I do know that a long time ago a benchrest gunsmith of national reputation told me that he had a fixture that he used to correct the face to hole axis alignment of steel bushings. Personally, I would rather just start out with something that was straight to begin with. IMO if carbide and steel were the same price, I don't think that there would even be a discussion about which one to use. When I checked my one and only carbide bushing with a neck mic., it came out on the same tenth all the way around. I found this encouraging.

 

[Larryh128]

I can't imagine that any bushing isn't ground. It should make very little if any difference whether you have a TICN coated or carbide bushing. Both are extremely hard and aren't going to be hanging up on a neck.

 

[butchlambert]

Larry,
Have you used solid carbide bushings?

 

[bozo699]

Bob,
With all due respect I think your asking a lot out of your equipment, I mean 80% with +or- .001 that tells me your brass is near perfect and 20% isn't as good. I shoot 1K and strive for the least runout also. I learned to take it in steps, if your chamber is .296 then your measured fired round is probably just over .295 so I would size it with a .294 and if you have multiple bushings of the same size like I do then do some measuring and you might find a .2935 then size it on down to your .292 although .003 is quite a bit of tension. measure your bushing on one side then measure the other side sometimes there is a little difference. Are you also turning or reaming the inside neck? I turn the outside before fireforming then after there fireformed I use my Wilson trimmer and inside reamer to finish the job. However you have to realize when you initially turn your brass and it hits way harder on one side then the other its obviously thicker on that side and its not just in your neck its all the way through that piece of brass so as you get some firings on that brass and the brass flows forward then your necks are getting thicker and thinner again so naturally concentricity and bullet pull will suffer, you may have to full length size with a standard die again and re turn the brass after a few firings. I hope it all works out for you.
Wayne.

 

[bozo699]

Bob,
I forgot to mention when I am turning my brass for the first time I take the lightest pass as possible maybe .0003 or so and if 2/3 or more of the brass is shined up with that small pass I know the brass is very close in thickness and will separate that brass, don't worry you won't get a lot of it out of a single box of brass, I try to buy at least 500 at a time of the same lot, out of that if I can get 40 or 50 pieces that meet my spec's I use it for my record rounds and the rest for spotters and practice and the bad stuff for fouling.
Wayne.

 

[BoydAllen]

Along that same line, a friend, who has a lathe and mill, has made a gauge that allows him to check case wall thickness runout back near cases' heads, and that is how he sorts them. The indicator is one of the lever, test best style. He has promised to make me one. I know that he is not interested in doing it, but do any of you think that there would be interest in such an item?

 

[bozo699]

Boyd,
Absolutely would be interested in one.
Wayne.

 

[BoydAllen]

PM me your email, and I will send you a picture or two. They are pretty simple to make. Perhaps we can get someone interested.

 

[in2deep]

I just quickly run the loaded rounds through a concentricity gauge and cull the rounds with .001 or less runout and use those for score then just use the rest to warm/foul the barrel and for sighters.
Always seem to get a few outies and doesn't matter which cases it seems the ones that grab or have a little more neck tension than the rest induce more runout and it may be that the resistance pushes on the neck/shoulder junction and bends them slightly.
Along the same vein I also went to lighter neck tension (under .001 thou) using a larger bushing and that seemed to help make straighter ammo.
A one piece Forster die (non-bushing die) with the neck honed out to your specs (Forster does it cheap) may be worth looking into if you don't trust the bushing dies.