I emailed Igman and they said they could supply in batches of 200, 800 or 1000 and ship to NZ(never asked how much as Robbie already has heaps and at a pretty low cost(about $65/100 is I recall correctly). I've fired these over 10 times now and still going strong! All up I've hard about 130 cases since the start and after damaging and learning a few things about would I was doing, I have about 90 formed now. So if 10 times each, 900 rounds down the barrel. I'll form another 100 shortly for winter wallaby trips.
Igman only do them in 12.7x99, 7.62x63, 7.62x51, 7.62x39, 5.56x45 - These are military cases so unlikely that 22-250 would be possible(but not 100% of that).
I would suggest reaming to 22-250AI for a bit of extra capacity. But I understand that most 22-250 barrels only have a 1:12 or 1:14 twist so you would still only be pushing about a 65gr bullet.
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