Runout caused by a bushing?? - Solved

[dstoenner]

Has anybody seen case runout being caused by a bushing?

I have a 6BR that initially I had issues with runout. After trying a lot of sizing dies I found that Whidden makes the dies right and my runout went away. The original Whidden was just the FL die. So when I started loading 260 for F-Open, I settled on a FL bushing die for my 260 after reading (as well as experiencing) the sizing button pulling the neck out. So I thought I would move to a FL bushing die for my 6BR. Every thing was fine till late this year. At about 2600 rounds down the barrel, I was starting to notice that if I went to the range with about 100 rounds, that at about 70 or so into the range session, the accuracy was falling off. Having gone though this on 2 other barrels, it days were numbered. I have been using 3 boxes of Lapua as my brass and had 9 firings on some and 8 on the rest. I don't anneal but thought why not send these off to DJ's brass service and get them annealed for the new barrel. So I loaded up all of the 8 firings so I could go get the 3 batches leveled and low and behold the loaded rounds were horrible. Yet when fired this brass all was 1 or less. This was a couple of months ago.

Fast forward to today and i was going about cleaning and sizing my returned annealed brass. Thinking things would be good. Well they weren't. Remembering back that earlier this spring I went from my 266 bushing to a 264 because I didn't seem to have enough neck tension. My theory was that after 9 firings, the necks were a little thinner. So I got out my 265 bushing and put it in and low and behold straight as an arrow like it should be.

It completely follows the 264 bushing. Just to be clear, I install the bushing with the writing down and I bring down the bushing stop to where it touches the bushing and then back it off about 1/16 of a turn and lock it.

I don't have enough instruments to figure out what is wrong with the bushing. I will buy another one and chalk it up to experience. Just wondering if anybody has tripped over this one?

David

 

[MagnumManiac]

Yes!
I no longer run bushing dies.
I had 2 problems with bushings:
#1 RUNOUT that a mandrel helped with but didn’t make it go away.
#2 DONUTS that took 3 extra steps to eliminate, sizing to push donut OUT, neck turning, then mandrel again.

Now I just order Forster FL Benchrest HONED NECK dies to my specs, I measure the neck and order a die that is .002” smaller than this in the neck, the expander is .001” larger than the neck which equates to minimal brass movement, no donuts and very good concentricity in the order of .001” or very slightly less.

Cheers.

 

[jepp2]

I will offer two different theories.

The bushing could have runout, some do. Read this: http://bulletin.accurateshooter.com...ading-checking-the-geometry-of-neck-bushings/

The second is my experience. I find if the expander has to increase the neck ID more than 0.001", it will pull the case neck off center. So when you went to the smaller bushing, you could have created the situation where the expander is now pulling the case neck off center. No matter if you lube, if you don't and where you have expander set (height).

As mentioned, honed case necks in FL sizing dies, give me the straightest case necks, PERIOD. So I now hone my case necks to get what I want.

 

[dstoenner]

I forgot to mention that i am not running an expander. I also bought a forster FL sizer and had forster hone it to 264. BUT it is too long and won’t set the shoulder back. I have found this to be true for the 6br and a 6x47 lapua i had done. Go figure. Everybody elses die oversizes. Hence why i use Redding match shellholders to adjust but that doesn’t work here at all

 

[dstoenner]

Thanks for the article. Seems to hit this one squarley on the head

 

[6MMsteve]

quit using bushing dies per acc shooter forums, also got rid of my lyman crusher, went with a old rock chucker i found brand new, runout went way down low .001 to .0007 groups shrank also

 

[243winxb]

Redding has info on there website. Sizing fired brass down more then .008" with a bushing , may cause it?? They recommend 2 step sizing.

If i remember correctly?

 

[Tim s]

What kind of bushings ?

 

[dstoenner]

What kind of bushings ?

These are all Redding steel bushings.

So after reading the article I went down with my calipers and measured the bushings. The 264 is egg shaped on the inside by .001. The others are a little better by about .0005 or less. But what is interesting it is always where the word Redding is stamped on the bushing. One bushing I have never used is the worst because it is .001 for 180 degrees not just maybe 45.

So does anybody know where you can get carbide bushings?

David

 

[AJC]

I forgot to mention that i am not running an expander. I also bought a forster FL sizer and had forster hone it to 264. BUT it is too long and won’t set the shoulder back. I have found this to be true for the 6br and a 6x47 lapua i had done. Go figure. Everybody elses die oversizes. Hence why i use Redding match shellholders to adjust but that doesn’t work here at all

So I was wanting to go this route. Will they turn down the base of the die when they hone the inside to fix the die?

 

[STS]

I have a box that has 40 or so bushings in it that I have used over the years. I have another box with 5 of them that are not concentric and are junk. I check them with a tubing mic. It's pretty easy to find a defective one.

 

[dstoenner]

So I was wanting to go this route. Will they turn down the base of the die when they hone the inside to fix the die?

I don’t know the answer to that question because I didn’t find out about this till i had received them back and started to try and figure which of my redding match shellholder to give me the right setback for my new barrel and it wouldn’t work. Even at 0 neither touched the shoulder and that shoulder was 4 mils longer than the go gauge. My Whidden die at 0 will set a shoulder about .006 shorter than the go gauge.

If you do go that route let us know if the will shorten a die also

David

 

[varget204]

Redding , RCBS, and Hornady make Hardened bushings.I believe they are all inter changeable in Redding,Rcbs,and Hornady dies.The steel one's do not Hold-up like the Titanium or coated bushings.The Hardened one's cost 2-3 times as much;but it's money well spent if you load a lot.

 

[MagnumManiac]

If the Forster die doesn’t move the shoulder, you can use a body die to bump with first, then the honed neck die.
If you do it the other way, the neck sizing first can change the shoulder at the juncture.
I always use powdered graphite on my expanders too, even though I’m not dragging it through a tiny hole, it helps keeping everything straight.

Cheers.

 

[Tim s]

These are all Redding steel bushings.

So after reading the article I went down with my calipers and measured the bushings. The 264 is egg shaped on the inside by .001. The others are a little better by about .0005 or less. But what is interesting it is always where the word Redding is stamped on the bushing. One bushing I have never used is the worst because it is .001 for 180 degrees not just maybe 45.

So does anybody know where you can get carbide bushings?

David

While I suspect a caliper measurement leaves something to be desired, the best ones are the titanium nitrided ones, pretty Popular in BR dies.

 

[L.Sherm]

So does anybody know where you can get carbide bushings?

Get CRT/Whidden bushings.

 

[dstoenner]

If the Forster die doesn’t move the shoulder, you can use a body die to bump with first, then the honed neck die.
If you do it the other way, the neck sizing first can change the shoulder at the juncture.
I always use powdered graphite on my expanders too, even though I’m not dragging it through a tiny hole, it helps keeping everything straight.

Cheers.

I also use graphite on my necks. I don’T have a sizing button to pull through but it helps get the neck smoothly in and out of the die.

Yes I am considering using my Whidden die without a bushing as the body die and then the Forster as the neck sizer

After all of this today I have ordered from Whidden the 3 bushings I use the most and will give it one last try.

Thanks everyone for the help

David

 

[_Raining]

I don’t know the answer to that question because I didn’t find out about this till i had received them back and started to try and figure which of my redding match shellholder to give me the right setback for my new barrel and it wouldn’t work. Even at 0 neither touched the shoulder and that shoulder was 4 mils longer than the go gauge. My Whidden die at 0 will set a shoulder about .006 shorter than the go gauge.

If you do go that route let us know if the will shorten a die also

David

I had this issue with my 6 Dasher. I contacted them and they said they would remove material from the base of the die. I'm lazy so I have not sent them out yet but I am about to fire-form my last batch of 100 so I'll have to send it out sooner rather than later if I want to bump the shoulder.

"Thanks for contacting us about this, with the Dasher not being a SAAMI cartridge, there is some guessing that occurs with both rifle and die manufacturers. We can likely shorten the die. I would send a couple sample ready to size cases for our review along with your requested sized for honing. There is a $12 machining fee for both services, plus the actual return shipping, we can call you for CC information upon completion."

 

[One Shot One Thrill]

Has anybody seen case runout being caused by a bushing?

I have a 6BR that initially I had issues with runout. After trying a lot of sizing dies I found that Whidden makes the dies right and my runout went away. The original Whidden was just the FL die. So when I started loading 260 for F-Open, I settled on a FL bushing die for my 260 after reading (as well as experiencing) the sizing button pulling the neck out. So I thought I would move to a FL bushing die for my 6BR. Every thing was fine till late this year. At about 2600 rounds down the barrel, I was starting to notice that if I went to the range with about 100 rounds, that at about 70 or so into the range session, the accuracy was falling off. Having gone though this on 2 other barrels, it days were numbered. I have been using 3 boxes of Lapua as my brass and had 9 firings on some and 8 on the rest. I don't anneal but thought why not send these off to DJ's brass service and get them annealed for the new barrel. So I loaded up all of the 8 firings so I could go get the 3 batches leveled and low and behold the loaded rounds were horrible. Yet when fired this brass all was 1 or less. This was a couple of months ago.

Fast forward to today and i was going about cleaning and sizing my returned annealed brass. Thinking things would be good. Well they weren't. Remembering back that earlier this spring I went from my 266 bushing to a 264 because I didn't seem to have enough neck tension. My theory was that after 9 firings, the necks were a little thinner. So I got out my 265 bushing and put it in and low and behold straight as an arrow like it should be.

It completely follows the 264 bushing. Just to be clear, I install the bushing with the writing down and I bring down the bushing stop to where it touches the bushing and then back it off about 1/16 of a turn and lock it.

I don't have enough instruments to figure out what is wrong with the bushing. I will buy another one and chalk it up to experience. Just wondering if anybody has tripped over this one?

David

Not sure what kind of accuracy you are looking for but at 2600 + rounds on a barrel it has past its peak. Most likely if the first 70 rounds are good it is the combination of carbon/copper fouling affecting your accuracy. Just for fun if you experience this again try pulling a bore snake thru to Nick off the carbon and see if that helps.

 

[Milo 2.0]

Not sure what kind of accuracy you are looking for but at 2600 + rounds on a barrel it has past its peak. Most likely if the first 70 rounds are good it is the combination of carbon/copper fouling affecting your accuracy. Just for fun if you experience this again try pulling a bore snake thru to Nick off the carbon and see if that helps.

I'm with ^^^, the more the barrel wear, the more rds you can get between cleanings, if done properly. A 2600 rd count is a fair amount too, how accurate are the first 70rds?