Ideal sized neck expanding mandrel~?

[COLT45SA]

My 6mm PPC has a .262 chamber. The brass thickness in my cartridges runs from .008 to .0085. I've crushed several necks after using a die with a .241 expanding ball and am wondering if a .243 expander would provide enough tension after "spring back". Or maybe even a .2425~!!

 

[Richard Jones]

My 6mm PPC has a .262 chamber. The brass thickness in my cartridges runs from .008 to .0085. I've crushed several necks after using a die with a .241 expanding ball and am wondering if a .243 expander would provide enough tension after "spring back". Or maybe even a .2425~!!

1. A larger expander doesn't make sense if you're crushing necks. Are they getting crushed in the bushing or when the expander hits it? At .241, the expander shouldn't even touch it. Confused. What size bushing?

2. Pitch the expander. Bushing only, then mandrel if needed.

Maybe I'm missing something here. @COLT45SA

 

[Bill Norris]

Agree with Richard on moving up in expander size. If a 241 is crushing the necks then a larger one would be increasing the results. Size with bushing and THEN run an expander in if needed. I get better results using a 240 expander in my 6 PPC necks when and if I use it.

 

[COLT45SA]

Interesting when you suggest a .240 expander. Mu bullets measure .243 and I don't see how you expect to stuff a .243 diameter dowl (bullet) into a .240 hole (case neck)~!!

 

[Eagle Six]

@COLT45SA why not a .242?

What ID are your sized cases? With the chamber neck size and neck wall thickness the ID of the neck cannot be computed. Neck OD after sizing less the neck thickness would be close.

As far as tension it would depend on the goal line. If you magazine feeding is going to be different than single loading. if you are jamming and you want to slide the bullet to seat when you jam load, then you need only enough tension to hold the bullet until you close the bolt.

 

[EGBrown]

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