I don't think you need to wonder much longer about who copied who, because GS Custom started manufacturing their bullets in 1993 already when most other manufacturers, including Barnes, were still on 'core bonded' stuff!
Barnes TSX came up very recently with their design, clearly an effort to try to achieve what GS Custom has reached, but far off from what it should be when compared to GS Custom's superior design in all the different aspects required of a high velocity bullet.
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Jagter
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