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Old September 12, 2012, 01:45 AM   #10
Lost Sheep
Senior Member
Join Date: January 24, 2009
Location: Anchorage Alaska
Posts: 3,078
Let me comment on Mehavey's excellent advice.

A. When starting to seat, run a loaded case up in the ram to the top
Have the seating die in the press, but not screwed in all the way. You don't want the die and case to touch yet.
B. Screw the seating die in until it first touches the case. Back it off at least a quarter/half turn and lock down.
C. Screw the seating down and adjust to where it seats your bullets to proper depth (nominally middle of crimp groove)
Screw the seating STEM in. You may have to run the case up into the die a number of times, observing how far the bullet is seated each time, screwing the seating stem in a little bit further each time until you have the seating depth where you want it.

The die BODY should not touch the case.

The case mouth should be even with the (a) crimping groove.

D. Seat all bullets.
E. Unscrew seating stem a half dozen turns to get it well off the bullet
Better still, remove the seating stem entirely.
F. Screw the seating die down to where it first touches the (now) loaded case,

Run the ram all the way up AND HOLD IT THERE with the press' lever. When you screw the die body in, you will feel it make contact (by the resistance of the die screwing in) and by observing that the ram will start to be pushed down. You will see the press' lever arm move. Everyone forgets to HOLD IT THERE.

lower the case, and screw the die down another half turn

Not a half turn. Just a little. Run the cartridge into the die and withdraw to inspect. If there is not enough crimp, screw the die in 1/6 turn and repeat, advancing the die 1/6 turn each repetition until you have the crimp you desire. The crimp should just engage the crimping groove, but not actually dig into the lead.
G. Now crimp all the loaded rounds (now separate from any contact with the bullet.)

Congratulations, you have just performed with a 3-die set what everyone else does with the 4-die set (except for the post-sizing, which may or may not be a good thing).

The seating operation (3rd die) with the 4-die set is the "C" and "D" parts described above. The Crimping (4th die) operation is the "F" and "G" parts described above.

At what point in the chambering attempts do your cartridges resist chambering?

I usually refer to the 3-die set not as "deprimer, fluter and bullet seating", but as:
1) Deprime/Size
2) Case mouth belling (or flaring) (Lee also charges powder through their hollow "powder through" die)
3) Combination Seat/Crimp

If a 4-die set:
1) Deprime/Size
2) Case mouth belling (or flaring) (Lee also charges powder through their hollow "powder through" die)
3) Seating
4) Crimping

Both revolvers and semi-auto handguns can benefit from the 4th die. For most of us it just makes die adjustment easier. You don't have to adjust Crimp and Seating together in one die, where changing one adjustment affects the other. Adjusting in separate dies is simpler. Revolvers usually get a roll crimp and semi-autos usually get a taper crimp. Bottlenecked cartridges use an entirely different "Factory Crimp Die" and nothing that applies to the FCD for straight-walled cases applies to bottlenecked (rifle) cartridges.

The 4th die (By Lee, but not other makers) from Lee, the FCD or Factory Crimp Die also provides (as I mentioned earlier) a "Post-Sizing" function. Some people find it unnecessary and some find it counter-productive. It can squish a lead bullet smaller than an ideal fit to your bore.

Unless your bullets are oversized, you don't NEED the FCD. You might want it anyway, but you don't NEED it.

Step "H". With the seat/crimp die body touching the case, fully crimping the case mouth, screw the seating stem down until it firmly kisses the bullet. Your Seat/Crimp die is now adjusted to perform both the seating and crimping operations simultaneously. Or pretty close. You may have to fiddle with it IN SMALL INCREMENTS to get it perfect.

Let us know how everything comes out.

Lost Sheep
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