[Swany]

I've read with interest about a lot of folks on the boards, fire forming 30-30 brass into .375 or 38-55, I have a 38-55 and made a new expander for my lee dies and what I did was to make one out of bronze that is shaped like a long bullet, tapering up to a flat .375 the length of the case mouth to the start of the shoulder, I generally lose about 5 of 100 due to splits now mind you I do this before they are deprimed as don't want any extra work for that 5 of 100, just a spray of Hornady One shot and I upsize in one stroke. Take care and have fun. Swany

 

[Bandito]

Neck Lube

Have you tried Imperial Sizing Wax? I use it on 7.62X51 brass to size up to .358 WCF. Good luck. Bandito

 

[ribbonstone]

That's about par for the course with used brass...the more used, the higher the failutre rate. Some factory loads are agressivly crimped with a kind of 3-section crimp...they often fail at the junction of the crimp segments. 30-30's are pretty cheap, so living with a 5 or 10% failure rate is acceptable.

Will find that the reformed cases have thinner case mouths than .375 brass...and thi8nner than most 38/55 factory cases. So long as your dies/expander still allow a firm grip on the bullet, no foul. May even help...it does when I want to use .380" bullets

 

[Contender]

Here is an image of a Lee 375 H&H EZ Expander. You can chuck this in the collet of your sizer die and expand the case necks up to what you need. They are tapered nicely and cost about 3 bucks plus shipping. Spin it in your drill press and use a hacksaw at the decapper pin to remove this portion of the stem if you want.

http://www.leeprecision.com/catalog/parts.cgi?1062633392.300=90559

Regards