Head size difference

[andym79]

Hi guys I am wanting to do a 35-90.

The idea going through my head at the moment is to use 45-90 brass and a 350 rem mag reamer run in .375" short. Using dies cut short too.

My only concern is case head diameter, being .513 for a 350 and .506 for a 45-90!

Is a .007" difference too much or okay?

I am hoping to end up with a rimmed 35-90 using cast bullets and either bp or trailboss so pressure will be low, but will I likely get a bulge at the head or worse a split?

 

[Swampman]

I can't give you an actual answer, but American made 6.5x55 Swede cases have been made with .472" head size and the CIP standard is 12.2 mm (slightly over .480").

I've seen cases that showed noticable expansion above the case head, but I can't recall hearing about any catastrophic failures that could be definitively blamed on undersized brass alone.