you wont go wrong with any of the 3 options - all are a significant step up in fps over 7mm08 (which is still a damn fine choice for most NZ hunting situations). I own all the above - 280AI is a sentimental fav & gets me to 800 yds, the down side is long action and you'll need a 24 in (or longer barrel) to ring the best velocity out of it. More of an open tops rifle than bush bashing & in light weight rifle its kicks pretty hard. The 284 seems to be an underrated calibre in NZ (no factory ammo), but those who own them or shot with them know how good they are & you can run short barrel & light weight rifle with really good performance. Recoil with a suppressor is super light ... like non existent. In my experience 284 speeds are slightly under the 280AI, but based on 20 in barrel with bare rifle weighing in at 5.6 lbs its damn nice rifle to carry on the hill, especially bush stalking (built on Weatherby MK5 ultralight). SAUM short action REM model 7, 22 in bbl in STUG stock weighs in just a sniff under 6lbs bare rifle, and 162 AMAX doing 2930fps 0.5 moa groups. Pretty hard to beat. You're spoilt for choice ! Only down side on Tikka's is fighting the mag length, but if you go 284 on long action that should not be an issue.
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