300 RUM - hard to get cases out of die

[NotEnoughTriggerTime]

I am starting reloading my 300 RUM. Today I was full length resizing my brass (rem cases), and had a bear of a time getting them out of the sizer die. MAJOR effort! the downstroke seems pretty normal, but once the case neck hits the expander on the way out, it takes a major pull to get it out. Some were worse than others. I ran into this mainly on 2x fired brass (factory load, then reloaded once and fired).

What am I doing wrong, or should be doing different?

Inside neck reaming maybe? is this done before or after resizing?

My best load so far is 90.2 gr of H1000, 200 gr SMK, Fed 215M Primer. no chrono yet, but 3/4' group.

 

[Varmint Hunter]

Dirty case necks (inside) or excessive resizing of the neck can both cause the difficult neck expansion that you have been experiencing.

Just my thoughts - VH

 

[Guest]

Are you cleaning the inside of your necks and then lubing them? I was having a similar problem with my 22BR and after cleaning necks with a brush then lubing the inside with a Q-Tip and Imperial sizing wax the problem went away. Sometimes the die will size the neck way too small then the expander ball has to work the brass real hard to expand it back to size, this is the case with my 22BR dies. You can take out the expander assembly and size one case then measure the od of the neck. The RCBS dies for my 300 RUM will size the case neck od to .333" then with the expander in place it is .335" and with a bullet seated it is .338". My 22BR die sizes the neck down .010" under the size it should be. I called the manufacturer and they said send in the die with a few sample cases and they will open the neck up. Hope this helps some.
Wayne

 

[sniper2]

Try polishing your expander ball!

 

[dwm]

I had this exact same problem real bad with some Hornady dies.

The first thing I tried was to use the Hornady spray lube to lube the inside of the case necks and outside of the cases when sizing. Similar to Wayne's suggestion, lube the inside of the necks. This works to some extent but does not always solve the problem completely.

The problem went away when I tried an inside neck reamer. I am pretty certain I was reaming the doughnut out of the bottom of the case neck. This is not a precision process so no one recommends it.

I finally figured out that the case necks had an uneven thickness and/or were too thick to work with this type of die. There are a couple of ways to solve this.

Option 1. Take out the expander shaft and ball. Put it in a drill, spin it up and polish/turn down the expander ball a bit with some steel wool or very fine sand paper.

Option 2. Turn the case necks just enough to even them out and make them thin enough to work with your existing expander ball. You do not have to turn the complete neck, just enough to make about 80% shiny. If I were to use an expander ball I would still use the Hornday spray lube to lube the inside of the case necks.

Option 3. Get some Redding bushing dies or equivalent dies that do not use an expander ball. This solves the problem completely. There is nothing to pull through the inside of the case neck.

Option 2 solved the problem and the Hornady dies now work again. Can increase the accuracy of factory chambers also. Lots of work though.

Now I turn all my case necks a little to even them out/make them uniform. I also bought a complete set of Redding bushing dies for all my cases and do not use the Hornady dies any more, problem solved.

Lee collet dies work completely different and do not have an expander ball. They also do not have this problem. I do not have much experience with them though.

 

[NotEnoughTriggerTime]

thanks!

I think all of the above apply - I presently size the fired cases, resize, then put them in the case cleaner to remove the case lube. I was not cleaning or purposly lubing the inside of the case necks. I assume someone makes a case neck cleaner/lube rig for the bench top, I'll check Midway.

Although I din't origionally mention it - these are Hornady dies also. Polishing the decapper/expander sounds like a good idea.