I couldn't find any Lee 300BLK dies around, so I got Hornady. How in the HELL do you adjust a seating die to seat and crimp in one pull? I followed the instructions several times and always end up with either a seated bullet and no crimp (bullet creeps forward (longer) in the case when AR slams it into chamber) or I crush the damn case during seating. I've been reloading for several years, but have always used the Lee factory crimp die. With the Hornady die I can get a crimp OR I can seat a bullet. If I have to make 2 passes, I might as well use the FCD. I have one on the way from MidwayUSA, so long term I'm good. I'd still like to figure this out.

For the record here's what I did:

1. Ram up w/ cartridge in shell holder.
2. Screw down die until resistance.
3. Back out die 1 turn to prevent crimp.
4. Adjust seating knob to get correct depth.
5. Back out seating knob 2 turns.
6. Screw die in 1 turn, then in small increments to get crimp.
7. Screw seating knob back in 2 turns + final adjustment.
8. Lock it all in place.

Where is the black magic that I'm missing?

I would start with your step 6, unless your full turn in doesn’t crimp any I would increase in smaller increments. Also I would turn the seating stem out more than 2 turns. The die body has a much coarser thread you don’t want the seater coming into contact with the bullet while adjusting your crimp

All your brass will need to be the EXACT same length if you plan to crimp with the Hornady die. It will crimp evenly based on the case mouth being constant. You have the right steps. When setting up to crimp, you have to adjust the die body separately of the seating stem, which it sounds like you are doing. The Lee crimp die is not sensitive to differing case lengths and crimps from the sides, not from above, which I like better. I run the Lee crimp die for 308, blk out, and 223.

Thanks! I'm just going to resign myself to not mastering this and stick with my Lee FCD.

Its really not difficult at all. Trim casings to same length. Get the bullet seated to the desired length. I always remove the seating stem then run the ram to top and screw die body in till you feel resistance, then lower ram and screw die in a little more and keep checking till you have the amount of crimp you want. When you have the desired crimp tighten down the lock ring and then screw the seating stem back in till it contacts the bullet tighten lock nut and done. Recheck to make sure you have the desired crimp and length and adjust accordingly.

That is good info.