Three-Five-Seven

[Iron Mike Golf]

What die set are you using?

If you are not using a Lyman M die (or one similar that has 2 steps to the expander diameter) and have not trimmed your cases to a common length, then you are subject to having the flare on some brass be more than what you set things up for.

When I have a case that's flared like that (I like to shoot new brass before trimming), I run it in the sizing die a tad (with a bullet sitting in the mouth).

Since you don't have a dedicated crimping die, you might look into the Redding Profile Crimp Die. It makes a nice roll crimp and the entrance is generous, accepting over-flared cases a seating die won't. I have one of these for most of my revolver calibers.

 

[Hammerdown77]

Is it the flare on the case mouth that is hanging up in the seating die, or is it the expanded part of the case below the case mouth?

How's your neck tension? If your brass is being expanded too much (not flared, expanded) then your neck tension can't be that good.

 

[Chuckbuster]

If by "FCD" you mean a Lee Factory Crimp Die, you might reconsider if loading cast bullets depending on your bullet dia./throat dia./ bore did. relationship. Sometimes the bullet diameter used to fit throat and bore correctly results in a loaded cartridge over "factory spec." which the Lee Factory Crimp Die sizes to, potentially giving you an undersize bullet leading to excess fouling and poor accuracy.

To illustrate, I have a .44 special Blackhawk that does best with .432 dia. cast bullets. Lee factory crimp die made with standard .429 dia. in mind causes problems for me. I know .003 don't sound like much, tell my Blackhawk

Not that big of deal for me as I single stage load everything so I just seat a batch then run then reset the die and crimp. Application of the Lee FCD makes the most sense to me if loading for an Auto that maybe has a tight chamber.
Kevin

 

[hammie]

@gibson: This is a great forum. The members are helpful and welcoming.

It sounds like you're way ahead of me in your reloading knowledge. One thing I always do with a 3 die pistol or two die rifle set, is seat and crimp in separate operations. Of course it means that you're re-setting your die twice in the same session, but in the long run, it has caused me fewer problems (fewer bulged cases and a more uniform crimp). But not everyone is as anal retentive as I am.

 

[pisgah]

Maybe I am missing something, but it sounds to me like your only problem is that you are over-flaring the case mouths. The flare should not even really be visible, and just barely detectable by touch -- only enough so the base of the bullet feels like it will almost fit in to the case, but not actually start in to the case for any appreciable distance. Any more, and there will be difficulty getting it in to the seating die, and you will get premature case neck splits from overworking the brass.