Die expander issues

[spudgun]

Need some advise. I have a Hornady resizing die in 6mm Creenmore and have easily used it over 2,000 times. Today I get issues with after sizing the case and then lowering it in the press when the expander ball tries to expand the inside of the neck it gets stuck and I really need to pull hard on the press handle to get it out.

I am using a case lube (One Shot). I cleaned the marks off the expander and retried another case and it still gets stuck and the marks come back.

If I apply a lot of lube to the inside of the neck it will be easier but still need to jerk the press handle to get it out.

Any advise?.

 

[358WCF]

Keep it clean... die innards & brass. What I've always done when getting a new to me set of dies is chuck the expander rod, or just the ball if it's removable, in a drill & polish with 400 grit wet/dry paper. Some expander balls can also use some tapering on the top side radius with a fine file but your Hornady wont need it. Dipping the case neck in powdered graphite/Imperial dry neck lube (I think Redding sells this now) should also help with the build-up your pics show. A nylon brush thru case neck before sizing isn't a bad idea.

 

[wagonman]

as cases get several firing and loading cycles on them brass flows from shoulder into neck and can do what your describing, before sizing see if you can insert a bullet in neck thru the shoulder if its a tight fit or wont push thru you got what's called doughnuts

 

[Coyotefurharvester]

Are you leaving the case fully in the sizing die for a short period? Then when you extract the spring back seems to make a tough extraction for the expander. Are the marks even all the way around?

 

[Pawnee Bill]

My advise:: Get rid of the expander ball and switch to a mandrel. Problem solved.

 

[chromatica]

Cases will work-harden after being sized 5 or 6 times. This makes it very difficult when sizing. It might be time to anneal the case neck and shoulder to return them to their original pliable state. Annealing is a process where the brass is heated up to a temperature of about 700 degrees F. There are plenty of threads on this forum about annealing.

 

[243winxb]

Donut at neck shoulder junction? Neck turn or use bushing die.

 

[NZ_Fclass]

One Shot spray is rubbish. The wax works OK...but Imperial sizing wax or dry lube is best.

 

[Martin52]

....A nylon brush thru case neck before sizing isn't a bad idea.

^ This, run a brush through the necks to clean out any build up. Spin the brush (bronze if necessary) in a drill for 5-6 seconds. Putting lube on top of a build up will only work for so long.

 

[PRR1957]

The sizing button in most resizing dies are made from mild steel which can be galled easily by the carbon residue in the cases neck. Polishing the expander button will work for a while, but it will gall again and it’s the brass that is scraped off as the sizing button is pulled up through the case neck and adhering to the expander button causing more galling. This action will create a ruffed surface to the brass inside the case neck which can affect bullet seating and release during the discharge of the cartridge. This also will pull the case shoulder forward changing its shape and causing undo case neck strech. The problem with repeated polishing is that over time the expander button can be reduced in O.D. causing the case neck I.D. to be under sized. Some of the die manufactures offer a carbide sizing button, but they are pricey, but worth the money. As others here stated to lubricant the inside of the case neck prior to resizing, but after so many cases the decapping/sizing button stem should be removed to wipe off the accumulated sizing lube and carbon. I use RCBS Case Lube 2 applied to inside of the case neck with a nylon bore brush. I do have to wipe off any case lube that gets on the outside of the case neck so it cant migrate to shoulder region of the resizing die and cause hydraulic denting of the case shoulder. This does require the cases after resizing to be run through a case polisher to clean out the cases lube. I use fresh ground corn cob for this, but alternatively RCBS Case Lube 2 is water soluble and in the past I’ve washed the case lube off the cases in hot soapy water, then dry the cases in an oven set at 200°F on a cookie sheet for an hour.

 

[spudgun]

as cases get several firing and loading cycles on them brass flows from shoulder into neck and can do what your describing, before sizing see if you can insert a bullet in neck thru the shoulder if its a tight fit or wont push thru you got what's called doughnuts

The sizing button in most resizing dies are made from mild steel which can be galled easily by the carbon residue in the cases neck. Polishing the expander button will work for a while, but it will gall again and it’s the brass that is scraped off as the sizing button is pulled up through the case neck and adhering to the expander button causing more galling. This action will create a ruffed surface to the brass inside the case neck which can affect bullet seating and release during the discharge of the cartridge. This also will pull the case shoulder forward changing its shape and causing undo case neck strech. The problem with repeated polishing is that over time the expander button can be reduced in O.D. causing the case neck I.D. to be under sized. Some of the die manufactures offer a carbide sizing button, but they are pricey, but worth the money. As others here stated to lubricant the inside of the case neck prior to resizing, but after so many cases the decapping/sizing button stem should be removed to wipe off the accumulated sizing lube and carbon. I use RCBS Case Lube 2 applied to inside of the case neck with a nylon bore brush. I do have to wipe off any case lube that gets on the outside of the case neck so it cant migrate to shoulder region of the resizing die and cause hydraulic denting of the case shoulder. This does require the cases after resizing to be run through a case polisher to clean out the cases lube. I use fresh ground corn cob for this, but alternatively RCBS Case Lube 2 is water soluble and in the past I’ve washed the case lube off the cases in hot soapy water, then dry the cases in an oven set at 200°F on a cookie sheet for an hour.

The die I am using are Hornady. I tried polishing the expander ball with emmory cloth but it just gallded up again. Going to call hornady tomorrow to see if they will send me a new one.

Thanks to all that helped.

 

[PRR1957]

The die I am using are Hornady. I tried polishing the expander ball with emmory cloth but it just gallded up again. Going to call hornady tomorrow to see if they will send me a new one.

Thanks to all that helped.

It will just gall again. Lubricant for the inside of the case neck. Since I been doing that for more then the last three decades of four decades of reloading, case neck stretch and galling has not been a problem for me.

Another thing to consider is the use of a bushing neck sizing die be it either just resizing the neck or full length. The only caveat is that the case neck thickness shouldn’t vary more than .002” around it’s circumference. I use several bushing neck and full length sizing dies, but with most the necks have been turned. A high quality dial or digital caliper can be used to measure case neck wall thickness, but I use a Mitutoyo .0000” tube micrometer left over from my machinists days.

 

[JMayo]

Imo,
No need to use an expander or mandrel. Size em and load.

 

[divingin]

Keep it clean... die innards & brass. What I've always done when getting a new to me set of dies is chuck the expander rod, or just the ball if it's removable, in a drill & polish with 400 grit wet/dry paper. Some expander balls can also use some tapering on the top side radius with a fine file but your Hornady wont need it. Dipping the case neck in powdered graphite/Imperial dry neck lube (I think Redding sells this now) should also help with the build-up your pics show. A nylon brush thru case neck before sizing isn't a bad idea.

Personally, I use 800 or higher wet/dry, and lube it with some oil. I want to remove the brass on there, not take down the ball diameter.

Prevent it next time by getting some case lube on the neck interior prior to sizing.