Lee 357 mag expanding and powder die_

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Jan 8, 2017
When using my Lee 357mag powder and expanding die the brass is getting stuck in the die more than normal and takes considerable force to remove. Since I do not use the powder feature I was wondering if I would be better off using either the Lee universal expanding die or the Lyman M die? I do not need the added feature of shaking the powder.
How much flare are you imparting to the case? I usually only flare enough to get the heel of the bullet engaged, and no more - that's a really small engagement against the expanding die. If you're getting stuck with that little flare, I'd venture you have a lip cut in your expander.
Is it possible the die is incorrectly adjusted? It sounds like you are shoving the case too far into the die but it's only a guess from what you Saud in your post.

I have a set of Lee 38/357 dies and a dedicated set of Lee .357 Magnum dies and neither expander does what you described.
Very little bell. This is new starline brass. No problem with dry tumbled brass. Lee is sending new expander,mine has ridges in it.
Couple thoughts; new, extra clean brass will have a tendency to "stick" in the flaring die, so perhaps a but of lube would make things easier. But the easiest remedy would be to get a better flaring tool, like an "M" die...
It's the new brass! Stick a few pieces of brass that is still black/grey on the inside... the carbon residue will act as a dry lubricant!!
If I were to use the Lyman M die would I need to lube my cases? What about the RCBS or Redding copies?
You don't need to lube the cases. You just need to use some used ones for a little while! You already have everything you need to "solve" this problem. Go shoot the rounds you have made. Tumble them if you want to clean the outsides, but don't do wet washing or anything.... let the insides stay dark. Run those through the die. Mix them in with the new brass. Problem solved (especially over time as the die breaks in).

I would anticipate that any die that squeezes an expander down into a case will have this same trait.
I had the very same thing happen with my 9mm and 45acp brass after I started wet tumbling. When you use Dawn to clean the brass, the brass surface is absolutely bare. With dry tumbling, there is the dust and polish left over that acts as sort of a dry lube.

I read about someone using Armorall Wash-n-Wax so I thought I would try that. It leaves a very thin film of wax, no different really than the car polish that most people use in their dry media. Problem solved. Plus, the thin film also helps keep it from tarnishing later on.
I would anticipate that any die that squeezes an expander down into a case will have this same trait.
The Lee expanders tend to be rough to very rough (To shake the powder measure and keep it settled according to advertising), and they grab cases more than the more finely finished expanders from other makers. I polished all of mine, made a heck of a difference. I have also been replacing all expanders with Lyman M Dies or the RCBS or Redding copies. They simply help seat bullets straighter.
Personally, this is not a problem for me even though I experience it on occasion with spanking clean, or virgin brass. This is one of those problems that "works itself out" with use and fired brass. I guess my presses have enough leverage that I don't notice (an old C-H single stage, a Lee turret, a Pacific small C press, and my favorite, a Forster Co-Ax)...
the lee die just does that. if it bothers you, buy a different company's die.

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