I ran my 280 AI in a Cadex chassis with both AI and Accurate mags and never really had any issues with feeding. The shoulder angle made me think that I would, but I don't recall ever sitting there struggling with it. I never ran it fast, so I can't speak on how it would hold up in a match or somewhere where you are firing more rapid shots.
If the shoulder on my 257 Weatherby can feed reliably, then anything can!
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