Does your Redding type"S" bushing die do this to your necks ?

[Metal God]

Hello everyone , I've been having this issue for quite some time now and thought I'd inform you all what I have found . Although I "kinda know what's going on It's not completely clear as to why It's happening . Feel free to suggest what you think is causing the problem or other ways to fix it . For the most part this thread is a PSA to all that use the Redding type "S: bushing dies .

Now to the problem .

For quite some time now and really ever since I started using the bushing dies . I've been getting Flared or belled necks at the mouth . This does not happen with all lots of brass and appears to happen most with LC brass . Now I use MUCH more LC brass then any other so that may explain why It seems to happen with those only . I still need to test if any other brass does this as much as LC does . Although it is noticeable by the naked eye , It's hard to see at a glance . When you magnify the case and get a closer look it's clear there is a problem .

308 LC-( forget the year ) FL sized using bushing .002 smaller then the loaded OD of the neck WITH OUT expander ball.


5.56 LC-14 FL sized using bushing .003 smaller then the loaded OD of the neck WITH OUT expander ball.


These cases were once fired by military and bought from my local range . As you can see there is a clear belling and or flare at the case mouth which results in very inconsistent bullet hold .

Now if you use the expander ball when sizing the problem goes away .


Pretty crazy right ? yea I was starting to get pretty frustrated because If I have to use the expander to size my cases , Why use the bushing die ?

So I finally contacted Redding as well as talking with a couple experienced reloaders about the problem .

I emailed Redding and informed them of the problem I've been having . Before that I did some measurements and was very surprised as to what I found . I always thought that the case mouth was experiencing spring back that was causing the flare . Turns out the mouth is just about the right diameter as the bushing used but the rest of the neck is actually sized down an extra .004 o .005 then the bushing size .

Meaning : My loaded cartridge necks OD is .337 so I use a .335 bushing . After FL sizing the mouth measures .334 but the center and lower section of the neck measures .331 0r .330 . Wait what ??? the neck or part of it is being sized down .004 smaller the the actual bushing being used ??? Well that's not making any sense right ?????

So I emailed Redding and explained the issue . I'm leaving some of the back and forth out because some was just making sure we understood each other .

Reddings reply :

I have seen this one other time, however it happened with a regular
FL sizing die. Seems the gentlemen's chamber was rather large in the
neck and the die was reducing the case neck down a significant amount
causing the case mouth to flare.

In my experience I have not found LC brass to be consistent with
regards to neck wall thickness.
I do think the problem has to do with the brass itself and may be one
of following.

Inconsistent neck wall thickness.
For instance your 5.56 loaded round that measures .2465 tells me its
neck wall thickness is .01125". Now if you have a sized case having
an ID of .245 using .245 bushing w/out the sizing button, that tells
me its neck wall thickness is .015. That is a difference of .003475"
between the 2 cases.

Reducing the diameter of a fired case down by .008" or more could
create a flare on the case mouth. What does the neck OD of a fired
round measure, for both the 556 & 308? By subtracting the bushing
size from those measurements it will tell us how far down the bushing
is needing to reduce the case mouth.

The thing that is puzzling is that it doesn't happen on every case.
Right?

My response :

I should have been more clear on what cases have the issue and which do not . I buy my brass from my local range where the Navy and coast guard shoot . The range then sells there brass is 250rd lots . When I say not all cases flare . I should have said not all of the lots flare . If one of the cases in a 250ct lot flares then they all do . I have bought those 250ct lots where none of the cases flared . That's what I meant by not all have this issue .

I then went on to give him the measurements I had come up with . At the time I was testing the LC-14 5.56 brass . There was some confusion about my measurements between him and I but the final result/reply from Redding was

Redding reply

It is not uncommon for any one of the brass manufacturers to produce brass within this range from lot to lot or year to year etc. Therefore it is not uncommon for the reloader to have several different bushing sizes on his bench to accommodate different thicknesses. The only way to get around using 1 bushing size would be to turn all case necks to a consistent neck wall thickness. The only other option is to use a standard FL sizing die. You may find for your situation it might be best to use a FL sizing die for the LC brass you purchase and use the B/FL die for Lapua, Nosler or Norma. I have found those three to have some of the best quality as well as most consistent.

With regards to a sized case coming out smaller than the bushing size. The only definitive way to determine if the bushing is in spec would be to have a machine shop pin it. You are also welcome to send the bushing back here where we can check it as well.

I have pasted below a quick explanation of how this can occur.
It has come to our attention through customer calls and our own use of the bushing style sizing dies that in certain instances, a given neck sizing bushing will produce a case neck diameter that can be several thousandths of an inch smaller than the actual diameter of the bushing. This idiosyncrasy occurs when the neck diameter of the fired case is a great deal larger than the diameter of the neck sizing bushing, such as occurs when factory chambers are on the large side of the tolerance range. Typically, we have not noticed any problems until the case neck is reduced more than 0.008-0.010". (your fired case .254 - .245 bushing = .009")

Solutions include, increasing bushing diameter to compensate and/or the use of a size button. Reducing the neck diameter in two smaller steps by using an intermediate diameter bushing will also help. More concentric necks will also result using this method, as the case necks are stressed less during sizing. Don't forget to properly chamfer the inside and outside of the case mouths and apply a light coating of lubricant to the case necks before sizing.
.

Now If you use the expander ball it reforms the neck and all works just fine but that defeats the purpose of the bushing die

The fix so far is to size the neck down in increments . Lets say you want to size the outside diameter of the neck to .245 but your fired case neck measures .254 . You first must size it down with a .250 bushing , then again with the .245 bushing . I can confirm that this does work .

There is another way how ever that seems to work well . You can use a Lee collet neck die to size the neck down first then run the case through the FL bushing die with the proper bushing . That also works and stops the belling of the case mouth .

I how ever found a silver lining in all this . I use a universal de-capping die to deprime all my cases first . I then clean primer pockets and brush inside of necks before first tumble . Instead of using the universal die to de-prime . I de-prime when I do the first neck sizing . For me and my process there is no extra step really just a different one .

I've been holding off on posting anything about this until I had a full picture to provide you all .

What say you ??

[J-cat]

It's normal for a bushing die to do this. That's why I don't like bushing dies.

[Metal God]

I have this thread going on a couple forums . I just got this link . It says this is a known problem with bushing dies and explains the two step process in detail .

http://riflemansjournal.blogspot.com/2010/04/reloading-two-step-sizing-and.html

That's all well and good but I'm still confused as to how the bushing sizes the neck down smaller then the diameter of the bushing . In the testing I did There was a point someone suggested using a different lube . I'm not going to get into all the different ones I tried but it was at least 7 different lubes with all the same results . I still plan to test a couple more lubes like molybdenum disulfide powder or even STP which I've heard is pretty slick .

EDIT : I should add that I did try annealing the cases first . That did not seem to help , If it did it did not help enough to remove the problem .

[J-cat]

It's how the brass is moved through the bushing. Brass is elastic and flows through the bushing in a "S" pattern. The amount of curvature that remains depends on brass hardness, the amount of brass you moved at once, and the thickness of the neck walls.

I could tell you how I really feel about bushing dies and the people who advocate them but I'd be instantly banned.

[fguffey]

If I had a die that sized cases that look like the picture of cases your posted I would ask for my money back.

Again, I was sizing the shoulder/body of cases before the die existed. When I did not completely size the neck down to the shoulder/neck juncture the neck had two different diameters.

F. Guffey

[J-cat]

That is correct. The neck has several different diameters: different at the case mouth, different in the middle, and different at the base. This is the nature of the beast with these bushing dies.

Stupid bushing dies.

[fguffey]

When I did not completely size the neck down to the shoulder/neck juncture the neck had two different diameters.

I had two diameters, I never had anything as ugly as the cases pictured.

F. Guffey

[J-cat]

I agree. Ugly as hell. They need to wear a bag.

[Metal God]

I agree , they are some of the worst cases I've ever seen . How ever , like posting groups online . I cherry picked the best pic to show the issue . I took that picture in such a way to high light the problems then zoomed in . They don't look as bad as they look . eer wait whaaat ??? It's only a .005 total flare so .0025 on each side . It is hard to see with the naked eye . Just look at the third pic above . The cases on the left are some of the same cases but they don't look that bad in that pic .

Also , The dies don't do that all the time . I just sized 120 LC-12 LR cases that came out perfect when sized only once .


I don't see the need to replace them or send them back right now but I may in the future . I have to say though . This has changed my opinion of these dies . I no longer feel I will recommend them with out pointing to this thread to be sure who ever it is understands what they may be getting in to .

It's why I did not recommend them in the recent closed 308 die thread . The OP said he was using LC cases and I felt it would have been wrong to say anything good about the Redding bushing die for what he would be doing and using .

That said I have loaded some very accurate ammo using these very dies sizing only once , so I know they work . It's now coming down to how much effort I want to put into these cases . I already do a tone of case prep to get these cases shooting well . The fact I don't need to do an extra step to fix the problem helps . I just change the first step from de-priming only to de-prime and neck size .

This was truly to be a PSA . I'm betting this is happening to more people then they realize . I hoping this will help a few folks out .

[J-cat]

Most folks don't have that amount of attention to detail.

[pacrat]

MG, thanks for the PSA.

I find it odd that Redding gives the opinion that "it happens". At certain times, with certain cases, and certain chambers. Yet gives no actual physical explanation as to how, or why it happens.

It does mean that for those who stick with their bushing dies and use "certain" cases. They get to sell them another bushing for "$26.49. So they can double their number of sizing operations by sizing twice per case.

I have never used the Redding Bushing dies. I've always handled the neck dia after sizing. And bullet tension issues by other means. Which I will not go into. Because they are irrelevant to your issue.

One thing your observations didn't mention at lenght is the neck tension issue. Focusing mostly on the weirdness of the undersized neck config after sizing.

If you load the cases. As they come from the die, with undersized neck. When you seat the bullet. Then the bullet itself is acting as 'the expander" to open the neck to bullet dia. This has long been known to cause concentricity issues.

After 47 yrs of handloading, I thought I had a pretty good grasp of how cases react during different sizing processes. This is a head scratcher for sure.

Possibly, the brass at the very mouth of the neck has been work hardened more, due to the original crimp. Giving it more springback capability than the remainder of the neck. But that should be negated by annealing. And would not describe how a bushing is capable if sizing the case "smaller" than its own internal diameter.

Have you measured the actual diameter of the bushing? Just maybe it is out of spec. Which still would not explain why it is capable of double diameter reduction.

Head Scratcher for sure.

[liber]

MG,

The one thing I'm curious of is if there is any noticeable different between the LC-14 cases that didn't size correctly and the LC-12 cases that did?

IMO, given the fact that Redding knew about this is kinda deceitful. Although I can't think of a good way for them to attack the problem if it is only happening to a minority of their users. They could surely try to understand why some cases fail and others don't.

I was mostly curious if the case thickness is noticeably different between those two year or anything else stands out as making them different (i.e., appearance of shoulder or other).

[Metal God]

Unfortunately I did not do any extensive measurements of the LC-12-LR . The LR is important because it's there best brass they load match quality ammo in for Long Range . Even when the military shoots it . It's likely shot from a bolt action rifle with much tighter chamber tolerances then the semi or full auto they shoot the regular LC stuff from .

My thought is that LC-12-LR did not have as large a diameter neck to size down as the standard LC-14 . That's why they sized correctly .

That's my best guess .

[liber]

Were these all cases that had been fired out of your chamber, or is this the first sizing?

[Metal God]

Generally I'll say all have been once fired by the military and this was my first time sizing them . On all of them except the LC-12-LR I've had to remove a primer crimp so I know they were only fired once .

I say generally because if the case had the issue and needed the expander to be used . I always used the expander for that lot of brass the next time they were sized .

Some of this testing is a few years old so my memory is not remembering all the details . I kinda remember this happening even after I fired the cases from my rifle but can't be sure and that's why if I used the expander I kept using it . .

I keep all my brass separate in head stamp lots as well as times reloaded . I note if the expander was used and if it was on a lot of brass I use it again .