Was seating some Hornady 200fr FN interlocks in 358 wins this afternoon, winchester once and twice fired brass, die just kissing the top of the shell plate, and noticed I was getting these bulges when using the last bit of throw on the lever. Almost felt like it was camming over to crimp and instead I got this??
Any idea what I'm doing incorrect here?
How did you decide to set the seating die this way?
You've probably got the crimp ring of the die prematurely coming into contact with the case mouth.
Suggested procedure:
Back the seating stem out of the die body a good way. Then back the die body away from the shellholder several turns.
Place a case
with no bullet in the shellholder and raise the ram all the way. Screw the die body into the press until you feel contact. More than likely the bottom of the die will still be off the shellholder. So what is touching? It's the crimp ring inside the die hitting the case mouth.
Now that you've established the contact point, screw the die out a full turn and set the lock ring against the top of the press. That's the die setting for seating bullets.
Put a bullet on top of the case and run it into the die. If earlier you backed the seating stem out a sufficient amount, the bullet won't be very far into the case. Now use screw the seating stem into the die in small increments until you seat the bullet to the desired overall length.
If you wish to crimp I suggest doing it in a separate operation which I'll outline if you so desire.