seating stem for JHP

I have been loading LSWC and using the Dillon seating die with the seating stem that seats from the shoulder. I would like to start using the Zero 185 JHP and it seems like the LSWC seating stem does a better job of cupping the bullet than the "round nose bullet" seating stem does. Is there a seating stem shape that is specifically designed for use with JHP bullets that I should be using instead?

Reach out to Dillon, maybe the seater insert is misshaped and you can get a replacement.  Have had good luck with Zeros with Dillon dies.  

I had a Forster seater for 22-250 that left a ring in the jacket when seating. Replacement seater stem solved it.

The SWC stem is very likely just pushing on the flat defined by the hollow point.

You can make one….

Make a dummy round as best as you can at about the right length.
Find a seating stem you’re willing to modify and drill and tap a hole for a #4-40 cap screw (optional).  
Apply grease or cooking spray to the interior of the die and the seating stem except for the area that contacts the bullet.  Also spray the dummy round. Wipe the area Thad contacts the bullet on the seating stem with a patch or rag wet with brake cleaner or acetone.
Use some epoxy putty and make a small ball (maybe the size of a small marble) of mixed epoxy putty.  
If you’re using the screw, work it around the screw head leaving a few threads exposed.  
Screw the ball or press the ball into the existing recess and then thread the stem into the die.  Just before the ball of epoxy enters the die form the seating recess by pressing the bullet as straight as you can into the epoxy ball.  Remove the excess epoxy and screw the stem with bullet  into the die until the case stops on the crimp shoulder.  Set the die down on the round so the weight of the die applies some pressure.

When it cures, remove the bulletin then the stem.  It may seem stuck but probably isn’t.  Then I’d clean up the epoxy plug to be even and reduce the diameter to the original diameter of the seating stem.  

Easy peasy…