450Bushmaster.net

I'm looking at the seating die that comes with the Hornady set, and it appears that the crimp sleeve applies a roll crimp. I'm wondering why they would do that, given that the case headspaces on the mouth. Then there's a fourth die for doing a taper crimp. I'm planning on using the seating/crimp die for seating only and then applying the taper crimp in a separate operation. Is that how most of you are doing it? Any recommendations on adjusting the taper crimp die? There are no 450BM-specific instructions packed with the dies, and the Hornady Handbook says only that you should not apply "too much" roll crimp. Thanks.

you are correct on the seating die and roll crimping, my 450 and 460 S&W stems look identical, so guessing Hornady used the same for both.

I taper crimp till the mouth is .472-.473ish. It's a trial and error setting it but a cheaters way is to put a factory round in, and snug the die down to it to get you close.

Thanks, Al. That sounds like good advice. I almost never roll crimp any more, even for magnum handgun cartridges. If a proper taper crimp is good enough for the .50 AE, it ought to be good enough for just about anything.

On my Dillon 650XL I am using the seat/roll-crimp die for just the seating part and the seperate tapper crimp in the last station. The documentation that came with my die set gave pretty simple directions one how to use the seat/roll-crimp die to only seat.