The reason is simplicity, the most common action used for competition is the Rem 700 and it's clones, why you ask, is due to the simple nature of it's design and ease that it can be trued and aligned.
I have Rem 700 based target rifles, they are cheap to blueprint, barrel fit and stock, but, I prefer a classic Win Model 70 action for anything else, including original '98 Mauser, CZ 550 and my second favourite action, the Kimber 8400.
I really like Weatherby cartridges, at present I have 270 Weatherby, 300 Weatherby, 340 Weatherby and 375 Weatherby, but, I do NOT like Weatherby rifles, never have.
I think the problem with Weatherby's being not so popular, is due to this very platform, the interweb, all this talk about bullets touching the rifling and you NEED this for accuracy, has eaten it's way into everyones' minds and FREEBORE is somehow detrimental to accuracy, this, however is completely unfounded, as all of my Weatherby's are very accurate, maybe not benchrest grade, but they're not benchrest rifles, either.
It really makes me chuckle out loud when I see a question about how much a bullet should be into the rifling on an AR based rifle, seriously, why would you bother?
Cheers.
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