Case Volume

[spittoon]

What I did.. I took a 3006 case cut the neck off at the shoulder. lubed the case and ran it trough 308 dies. then trimmed them to 308 Case AOL . turned out nice> I have done this on a 308 match case to make 243 case. but the problem is the 3006 case will hold 1.3 grn less of powder than the 308 case. The question is with case volume where or what do i do? Would I take the 308 load data and take off 1.3 grains from the max and work the load down ? I wish I had a chronograph to check speed . it will be for plinking 147-168 bullets thanks

[bobbyfairbanks]

Start at bottom of load data. Work up from there. All load development starts low then works up

[spittoon]

I under stand I did not want to under charge the load. or end up with a compressed load.

[Delfuego]

The lower volume could be in the "case taper". After firing, it may equal out.

All things being equal; 308 brass is super cheap. Might be easier, safer and more practical to buy some once fired 308 brass...

[Hoser]

You might end up with really thick case necks. Not a big deal until you pull the trigger and the case neck cant expand enough and pressures skyrocket.

Using a quality micrometer, measure the neck thickness.

[Irving]

What are you gaining by doing this?

[spittoon]

You might end up with really thick case necks. Not a big deal until you pull the trigger and the case neck cant expand enough and pressures skyrocket.

Using a quality micrometer, measure the neck thickness.

There is a .005 on the O.D wall thickness .and I will probably split cases on the shoulder even if I anneal them . Also wonder what the chamber P.S.I would be I do not think it would be a big deal .IF the cases make it through fire forming it is a plus.

[spittoon]

What are you gaining by doing this?

Well I have POOO ton of 06 case and to much time on my hands lately.

[Irving]

Well I have POOO ton of 06 case and to much time on my hands lately.

That's as good of a reason as anything I do. I was just curious.