| Well this looks like as good a place as any for this, and I can't seem
to find the answer anywhere else in this file.
I have a set of Lee dies that when I am doing the resize/deprime, the
downstroke (per handle) seems to go fairly smooth (using Lee lubricant)
but the upstroke is _extremely_ difficult. The deprime pin/interternal-
sizer seems clean of any gunk. I'm probably showing my ignorance again,
but does anybody know what in blazes is causing this?
fred();
|
| If these are bottle necked rifle cases, the expander button is
dragging on the neck. Even tumbling won't help. You need to do one of
three things.
1. get a case "graphiter" box. This lubes the inside of the neck with
either mica or graphite. Won't harm powder or primers. Midway has a
cheap one with brushes and a well for the mica.
2. get a carbide expander. These are available for Hornady, RCBS
and some others. It's basicly a replacement decapping rod, and may fit
your Lee dies.
3. get rid of the expander button completely, and get a Lyman "M" die.
This adds an extra pass, but uses a stepped expander plug that is
pushed down, not drawn back through the case mouth.
jim
|
| From: AUSS::HAGARTY "Dennis HAGARTY - ARC/ARMS @ OPTUS 04-Feb-1997 1557 +1100" 4-FEB-1997 16:15:43.33
To: CSC32::HADDOCK
CC: HAGARTY
Subj: Case necks and expander balls
Gi'day Fred();
Well, I can give you some more advice on the expander problem...
Firstly, you must clean out the necks - on the inside. This is best
done with a tumbler, it will clean the carbon out nicely. You can also
use a neck cleaning brush in a drill to do the same thing, or a
specialised case prep station.
Secondly, you must use some form of lubrication. I use graphite, I find
it to be much better than mica. I dip the cases necks (you don't have
to do every case - but it probably helps uniformity) in a shallow dish
of graphite.
Thirdly, you must make sure that the expander ball is the correct
dimension, like just under the bullet diameter. I cannot remember what
the proper dimension should be, but remember that the brass springs
back after working, so it should be usually a bit smaller than the
bullet diameter. You should probably end up with .002 or .003 of neck
tension (depending on application), so make sure that your button sizes
your brass down to approx .305 for .308 brass. You may have to
experiment to find out what diameter button will acheive this. If it's
too big, then attack it with some grit or something.
Fourthly, you must make sure that the expander ball is properly
polished. But, paradoxically, you must ensure that a very well polished
expander is lubricated - one not as nicely finished doesn't need the
lubrication as much. This is because a finely polished button will have
much more surface area in contact with the neck. You can polish the
expander ball with some 1200 grit and a drill. You should only remove a
few tenths of thou with it (if that).
By now, you should be neck sizing/expanding like a knife through
butter, but if you want to continue...
Penultimately, you could get a carbide expander ball. These really are
good, I have managed to retro-fit a few Redding ones to Hornady dies,
but originals should be now available.
Lastly, you should make sure that the expander ball is being withdrawn
through the case neck at a point where the lever is close to the bottom
of its travel as possible (not always possible with long cases). This
will increase the leverage.
This is BEFORE you go onto neck turning, no expander button, etc etc
Cheers
Dennis
|