Dillon Precision Big-Fifty - Manual (Page 8)

PART# 29023 3/8/2010
8
Choosing your dies
The Dillon BFR will perform well with any manufacturer’s standard 1½”-12 UNF threaded
dies. Be ware that many 50 BMG dies currently available are for use in single-stage
presses, and may have a sharp lead in, which may not be very forgiving in a progressive
press.
The Dillon 50 BMG full length carbide sizing/de-priming die is manufactured to minimum
tolerances. DO NOT run this die down to the shellplate and size your brass, it will undersize
the case beyond the specified minimum dimensions. We strongly suggest that a
headspace case gage be used to correctly adjust the size die. You MUST CLEAN AND
LUBE your 50 BMG cases before attempting to size with the 50 BMG carbide sizing/de-
priming die.
To adjust:
1. Move the handle down to raise the platform.
2. Screw the sizing/de-priming die into station one of your reloader.
3. The 50 BMG sizing/de-priming carbide should not touch the shellplate. It will undersize
the case beyond the specified minimum dimensions if screwed down to the shellplate.
Once you screw it in and touches the shellplate then back the die up 1¾ to 2½ turns. This
will give you a good starting point for determining case dimension. The die was designed
to allow for a very wide margin of adjustment for the shoulder setback.
4. Using one lubed, boxer primed, case to test your sizing and headspace adjust the die
as needed to achieve proper headspace. (Wipe the case clean of lube before inserting
it into the case gage. Lube will cause grit and dust to cling to the inner surface and cause
the gage to give false readings. The base of the sized case should fall between the high
and low steps on the base of the case gage. If it does not, adjust your die and resize the
case. It may be necessary to use another case for this step. Repeat this process until the
case falls between the high and low steps on the base of the case gage.)
5. When properly adjusted, with a case in the die, snug the lock ring and its set screws to
set the desired position.
The de-priming assembly
The Dillon de-priming assembly includes a carbide expander ball for neck expansion. With
the handle pulled all the way down and a case inside of the die adjust the de-priming
stem down until it stops and then back it up 1½ to 2 turns. Once adjusted, tighten the nut
to lock the assembly in place. The number one danger in reloading is attempting to de-
prime a live primer. Under no circumstances should you ever attempt to de-prime a live
primer.