I used a Mec 9000 for probably 60-70,000 rounds over the last 6 years. Don't use it much since I bought a new PW 800+. One thing I figured out about the MEC was that
it worked a whole lot better if you De-prime and resize all your hulls first. Then skip that step and start reloading the hulls in the primer/powder step.
Set the crimp starter to "Close" the mouth of the hull as much as possible. (Measure your empty hulls and set for the Tallest (longest) hulls.)
Remove the last stage "Finished hull sizer" ( last step before ejecting the finished shell ). If not set exactly correct for the hulls ( hulls all have to be the same length or it can't work)
it will mess up crimps.. You don't need it anyway.
There are TWO adjustments for the crimper. One for depth of the crimp plunger. This sets the total depth of the crimp. It is adjusted with the top threaded plunger screw and set with the lock nut.
The other is the Cam adjustment on the arm that pushes the plunger down. This sets the finished length of the hull. Adjusting the cam on the drive arm has a lot to do with the finished crimp.
(the manual, under trouble shooting tells how it works )
Measure your empty hulls and set BOTH crimp adjustments to work on the "Tallest", (longest) hulls. The shorter ones will be "OK". If you adjust the crimper to the shortest shells, the tall ones will
be over crimped and a real mess.
Another thing. If your reloads are going to be fired in the same gun all the time ( Except for autos and pumps) then resizing isn't necessary. Back the resizer all the way off, oil the hell out of it,
and just use it to deprime. The whole unit will work smother. And deprime as a seperate operation. With LOW BRASS, the resizer doesn't do much anyway. I know a bunch of Guys who never
resize 28ga. hulls and use them in different guns including autos without problems ! I don't think tha 28ga. is as suseptable to expanding as the larger guages. Especially low brass hulls. You
can't resize the plastic part anyway and expect it to stay resized. You would have to heat the plastic part and put it back in the factory mold to get it to actually go back to( and stay) factory size.
Keep the unit cleaned and "Well Lubed" !
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