Howa actions are actualy very strong and pretty well desgined , their bolt is very solid and comes with a M-16 style extractor , they have a flat bottom with intrigal recoil lug. The desgine of the Howa will haned anything that the Rem 700 can and probably a little bit more , the trouble may come when you try to get longer rounds to fit in the mag. Their are way around everything so either having a new mag box made or lengthening yours can be done but is it worth the cost?
I wouyld say that a 300 RUM should be doable without a whole lot of fuss but it may require the bulletys to be seated a little more deeply than one world like.
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