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This product is supplied with: Shellholder Jaws (028271-016), Large Primer Tube only for Primer Seater (011521-
011LG), Small Primer Tube only for Primer Seater (011521-011SM), Primer Assembly, Large for Primer Seater
(011521-101), Primer Unit, Small for Primer Seater (011521-100).
I
NSTRUCTIONS
F
OR THE
P
RIMER
A
SSEMBLY
Select either the large or small priming assembly and set it in place by coming from the back of the tool. Move the
assembly forward so that the front end is even with the milled surface the jaws travel in and so that the milled top sur-
face is squared right and left with the front of the tool. It is important to get this correct, as the primer tube bottoms on
the top of this flat surface and all dimensions are figured to this tolerance. One way is to lock the jaws to the center and
move the assembly forward until it hits the back side of the jaws. Bring the primer tube in from the top at this point and
you should be able to see that everything has moved into its proper place. Lock the set screw on the side of the base.
The supplied jaws will work on most boxer-primed cartridge cases having a rim thickness of .050 to .070 and are
easily identified and matched with a small dot on the .050 end. (See inset on reverse page.)
It is necessary to first determine which end of the jaws you are going to use and set them accordingly. Most load-
ing manuals give complete cartridge dimensions as part of the loading data for that caliber. Loosen the jaws slightly
and center the primer pocket on the priming punch by depressing the handle slightly. With slight pressure on the han-
dle, move each jaw onto the rim and lightly tighten the socket head screws. Rotate the case so that it moves freely; if
it does not, loosen the jaw at the point of friction, rotate the case, and relock the set screw. This is necessary because
the primer pockets are not always concentric and this method will build this tolerance into the setting. Now, lock the
jaws and try a few cases to make sure the jaws are properly located and locked.
There are two methods of using this priming tool. The primer tray has a roughened surface which serves as a primer
flipper when the press is agitated by hand in a circular motion. After the primers are all bottom-side up, insert the tube
in the channel at the end of the tray and tip the tool toward you and downward to the right. The primers will all run into
the tube. Hold the handle of the press down and put the tube into the tube channel of
the tool, place the tool on a bench or flat surface, and you are ready for priming.
The second method is with the tool mounted on a bench; of course, the tray cannot
be used as a primer flipper in this situation. Place the tube in the channel built for it as
shown in Figure A and brush the primers in that are one side up, turn the tube over and
brush in the remainder. In both systems, the anvil of the primer faces the slotted side of
the tube as shown. Use a paper clip to hold the primers until the tube is inserted.
Priming is the single most important operation in reloading. Crushed, broken-tipped
or protruding primers are either dangerous or will cause variations in pressures.
NOTE — Seat primers with a slow, steady pressure to avoid breaking the primer
pellets or setting off the primer. Avoid any sudden or sharp blow when working
with primers. Wear safety glasses when reloading and always position yourself so
that you will not be injured in case of accidental explosion. To dissipate pressures,
the primer tube is open. This opening should be turned away from you.
The tube bottoms against the flat surface of the primer housing (Part #013). The bottom of the tube must be fun-
neled in slightly for proper functioning. For several reasons, the tube is made of a light, soft material which may be
bent, filed or trimmed with a penknife. The slot in the tube also permits visual inspection to determine if any primers
are reversed. Always clean your primer pockets.
CAUTION — To avoid the danger of forcing a live primer against a live seated primer, place all unprimed
cases in a loading block with the rims up. While priming, keep additional supplies of primers, powders and
flammables well away from your immediate work area and out of the reach of children.
CO-AX
®
PRIMER SEATER INSTRUCTIONS
www.forsterproducts.com
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