I agree with Alex, forming brass for the MachIV is a snap but it does take forming dies $$$. I don't think there's a chance in the world Remington will bring out Lapua brass for the .17 Fire Ball but I sure hope I'm wrong for those who want it. You can form .221 brass from .223 such as Lapua and then down to MachIV but again more dies $$$. Another situation that will hopefully resolve itself is from what I hear, in a world of difficult to find brass the .221 parent case needed to form MachIV (barring making it $$$) is particularly difficult to latch on to. That would be the logistical issues I'd consider keeping in mind that forming cases etc. is a large part of the appeal to wildcats for most of us and could as easily be a positive as a negative depending on your point of view. One other thing to possibly consider is resale, it "might" be a bit easier to sell a factory chambered rifle to some who might not enjoy wildcatting. Decisions, decisions
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As Alex stated there isn't 27cents worth of difference ballistically between em, I have both. Both are great by the way so that helps the decision process.
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