Case capacity using military brass

[BARON]

I have a large quantity of once fired military 06 brass. I have a .270 and a 25-06 rifle and want to resize the 06 brass to be used in the .270 & 25-06. What should I look out for when forming the cases and what amount of capacity difference will the new formed cases be from a commercial case? I know that I have to remove the primer crimp & trim to proper length that's not an issue.

[flounderman]

fill one with water and pour it into a commercial case. Federal commercial cases have caused me problems by being less capacity than the others, and a noticable pressure difference with the same loads.

[izzyjoe]

FC cases are smaller capacity than most, Winchester seems to have the most capacity. I always start lower than starting loads.

[Artful]

I checked 308/7.62x51 NATO case capacity back in the 70's and found about 10% difference - I checked case capacity a couple of years ago and didn't find a difference - so segregate and check capacity. And be aware if you neck down you thicken up the neck and shoulder junction and may need to thin the brass

[country gent]

The old rule of thumb was to reduce loads 10% for military brass and work up from there. When necking cases down necks tend to thicken so Loaded round neck dia needs to be checked or nek wall thickness. Reaming neck turning may be needed. Another thing to watch is the concentricity of the neck walls thickness as it may be uneven. Cases sized down will lengthen so oal needs to be checked and a possible trimming ( this may be needed to square case mouths again also). Last is to anneal as reforming hardens the brass.