Questions about the Lyman carbide expander ball assembly for RCBS FL dies.

Curious if anyone is using this in their RCBS .223 dies and if they like it or not. Any potential problems I need to be aware of?

I got one recently and have it installed (less the decapping pin) but have not got to try it out as yet. Don't need or what to use this for decapping as I do that with a Lee universal tool before tumbling. Likely a good thing as the decap pin that came with the Lyman is tiny and looks like it would not last very long at all with crimped in primers...

Hoping this will allow me to use less or no lube in the case necks when sizing and/or prevent me from pulling the necks out as much on the up stoke. Not sure if it matters but brass is wet tumbled and necks are very clean.

Also curious what size a .223 expander ball 'should' be. I measured the ones I have and got .22250" for the slightly polished Hornady, .22155" for the slightly polished RCBS and the Lyman carbide ball measured .22205" straight from the package. 'Slightly Polished' in this case means a little bit of work with some 1200 grip paper followed by some buffing on a leather buffing wheel with some very fine compound. I did not go nuts trying to polish the expanders I had and spent very little time on them.

Appreciate any tips or advice here. :)

I use the Lyman carbide expander with my RCBS 223 dies.  I got mine after using the carbide ball with my Redding 308 dies and seeing the difference in sizing and pulling the shoulders out during expanding.

I initially used it in a small base FL sizer die but I started using a standard FL die about a year ago.  I really like mine and can tell a difference in pulling the expander through the neck.  I decap and wet tumble before sizing and use the homemade Dillon spray lube in a Ziplock bag method of lubing cases as well.

I usually dab a little Imperial lube on the carbide ball before I start sizing as well.  The lube inside the necks keeps things smooth after that.

The only tip I could suggest is to run the expander stem loose if you see high neck runout.  I found that if I tightened down the stem I would get as much as 0.009" of runout and typically 0.004" of runout.  I tried tweaking the stem to center it up but ultimately found that if I backed it out about one turn and let it float I would get about 0.001" to 0.002" of  neck runout with an occasional 0.004" flyer.  I use an o-ring to set the gap between the top of the die and the stem.

Below are the measurements for the factory RCBS expander and the Lyman carbide.

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Die with o-ring between die and stem. You can also see I am running the carbide ball fairly high on the stem and the decapping rod does not extend out the bottom of the die.
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I had a Lyman carbide expander ball on my RCBS 223 die.  The expander rod was a little thinner than the rod on their conventional die and when I encountered a Berdan case, the rod broke.  During the time before I broke the Lyman rod, it worked great.  Since it was my fault, I contacted Lyman customer service to buy a replacement rod, but they wouldn't sell me one.  I replaced the Lyman carbide expander with one from Forster and it also works great.

I have found it possible to skip lubricating the neck of cases using the carbide expander, but lubricating every 5th or 10th case makes everything go much smoother.  I have not found any potential problems unique to the carbide expander.  Just watch for Berdan cases, but that applies to any die.

If your experience is similar to mine, your carbide ball will join your gun and cable modem as something they will have to pry from your cold dead fingers.

Lyman expander ball in an RCBS small base die here. I decap and then wet tumble in stainless steel.  I lube by tumbling in a zip lock with emperial wax on sponge squares. It gets some wax on the case mouth and it’s all the lube I need. Works slick as snot

I just recently grabbed a tin of that as well after reading so many positive reviews about it here and elsewhere. Have not tried it yet and have also not read anything about your method of using it.

My plan was to try out the Imperial at the same time as the carbide ball and see what happens.

Much appreciate all of the advice so far here from everyone.

I have the Redding kit for the Redding S dies.
I have used this set up for over fourteen years and a carbide expander is definitely the way to go.
Normally, I use either Winchester, Remington and occasionally Lake City brass and have never needed any lube in the inside of the case necks.

However, I recently have tried Starline brass and that stuff is a different animal.  I need to use a case neck brush to lube every 3rd case or so of the Starline cases or they size really hard through the expander.
(but don't get me started on Starline and their sub-spec [short; 1.746" AND low case capacity] brass)

I wasn't going to post in this thread because I haven't tried the Lyman Carbide ball/shaft in .223.   I did buy one in .308 during a test on resizing machine gunned 7.62 LC brass.  I was testing ways to get better concentricity when using an plug expander in hard-to-size machine gun brass.  I was told that carbide plugs deformed less.  In that case it deformed my LC brass more.  I think it was caused by the plug's shaft being way too small in diameter and it flexed during the extraction from the case.  The original RCBS plug's shaft was way thicker, and did not flex.  The pictures above in .223 don't show that diameter difference....in fact the opposite.  But is the black Lyman shaft steel, or graphite?  I think mine was graphite and it dang sure flexed.

Maybe there's nothing to glean from the experience, since you are sizing .223, but I share what I learned anyway, and you can ignore whatever you want, or at least be aware the possibility might exist, that it might not actually improve anything and might even make it worse.

In my .308 experiment, I ended up polishing the stock expanders and it helped quite a bit.  After polishing I averaged .001"  but I sized then turned the brass 120d and sized again, repeated....in thirds.  Yes it will work harden....means you might want to anneal after shooting them, but I got really good results.

That was an experiment.  Do I advocate such.  No.  It works, but I'd rather buy Forster and have Forster ream my sizers to what I want and do away with the expanders, period.  If you buy their sizers they will ream them for something like $12.

Caveat?  Yup!  You have to buy sizers for each cache of brass you have that has different thickness in their necks....or inside ream the necks, post sizing, to make them all uniform.  Forster makes those reamers too.

Appreciate ALL of you guys chiming in with advice sir.

In my reading on the Lyman parts being discussed here I did come across a few posts in different forums about the rod being very easy to bend where the part that holds the headed pins screws on. I was hoping to avoid these potential issues by not using the Lyman for decapping at all and only using it for resizing after the brass has been deprimed.

The threads where the pin holder screws on are noticeably smaller on the Lyman unit than the RCBS as are the headed decapping pins themselves. RCBS headed decapping pins will NOT fit the Lyman rod (I checked) due to the size difference.

I definitely plan to try Kingston_fishers' advice pertaining to the use of an o-ring and see what that does for me. Looks and sounds like a great idea...