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Neck up or down

09 May 2020
@ 12:29 pm (GMT)

Wayne Woodard

Hi again.
What are the issues to neck down 308 to 7mm-08 and the best way to go about it. If their is info in the books please point me to the correct place. I have had a bit of a search on the forums as I know it has been discussed but no luck.
Would going up from 243 be any better?
In Australia so 7mm08 brass can be expensive.


10 May 2020
@ 08:14 pm (GMT)

Dale Wilhelm

Re: Neck up or down
I haven't tried do this myself so can't comment on which is easiest. However a note on safety. If you size down from 308 to 7mm be very careful that no-one picks it up thinking it is 308. Admittedly it will rattle its way down the barrel but not very well. On the other hand sizing up from 243 will end up with a round that could be very dangerous if someone tried to force it down their 243. In theory it shouldn't chamber but their are plenty of people out there that are dumb enough to try.
Personally I would just buy the right brass to be safe and to save a bunch of work.


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