Manual
The Corbin RFJM-22M
Rimfire Jacket-Maker Die:
K.O. Punch (used to push a jacket out of the die,
when needed to push out a jacket).
Die Assembly, consists of the threaded die holder
body (7/8-14 TPI), which screws into the press
head, the ring die insert which does the actual
drawing, the spacer tube, and the retaining bushing
(hexagon head, screws into the top of the die body
and presses against the spacer tube, which in turn
holds the ring die insert).
Ejection disk and tube assembly (press fit together,
slips over the punch and strips the jackets off the
punch on the down stroke of the press). Your press
ram must fit inside this tube in order to use the die
set on a reloading press.
Push rod, which can be used to finish pushing the
jacket through the die, after using the punch alone
to unfold the rim at the end of the stroke. The rod
adds about an inch to the travel of the ram, suffi-
cient to push the de-headed case through the ring
die insert. In the 6mm version, the jacket is NOT
pushed all the way through the die: it is ejected
after unfolding the head and used at original
diameter (it expands in the core seating operation).
Punch, used to push the case into the die just far
enough to draw out the rim into a straight section
without folds or creases. This is done at the end of
the press stroke. The push rod is the put into the
case and used to shove the case the rest of the
way through the die (for .224 jackets only).
How to use the jacket maker sets:
1. Clean and sort the cases. Separate them into groups by headstamp for
the best accuracy. Throw away any that are punched through at the firing pin
dent, or have been smashed flat. Boil the cases in hot water with detergent
and a couple of tablespoons of vinegar to remove corrosion and dust. Rinse
them in clean hot water and spread them out on an old towel to dry.
2. Draw the cases. Screw the die into the top of the press (hex nut faces
away from the ram). Bottom of the die should be from flush with the press
frame to about 1/8-inch below it. Insert the punch into the press ram (screws
into Corbin rams, slips sideways into regular loading press rams like a shell
holder). Corbin CSP-1 press must be in the LONG STROKE or reloading
position of the ram and toggle, not the short swaging stroke. With a film of
Corbin Swage Lube on your fingers, touch a small amount of lube on the
punch, and on the O.D. of the case. Put the case over the punch, and push it
into the die about 1/4 inch (the press should run out of stroke at this point).
Adjust the die so that the drawing is done at the END of the press stroke.
Only about 1/4-inch of the case is drawn down in this operation.
3. Anneal the cases. The cases must be brought to a temperature sufficient
to stress relieve and soften the brass, without burning it. Generally, if the
cases are brought to a barely visible red glow in a dimly lit room, they were
hot enough to avoid folding at the tip when you form the ogive later. A self-
cleaning oven generally gets hot enough. Spread the cleaned cases out on
an old cookie sheet and bake in the self-clean cycle of your electric range,
or heat the cases by using a propane torch to quickly bring them to a red heat
visible in dim light. Failure to anneal only means that the ogive may fold over
instead of drawing smoothly to a point. Let them cool to room temperature.
.224 (5.56mm)
PUNCH-M, and PUNCH-R
6mm (.243)
PUNCH-R, and PUNCH-M
You can convert
from .224 to .243
or vice versa just
by obtaining the
correct punch to
fit your press
ram! Type -R
punches fit the
reloading press,
type -M fit
Corbin presses.
-M -M
-R
-R