Doesn't affect gameplay at all, but the front sight and flash hider (on the model, not the attachment) on the Mk14 are inaccurate for that model of rifle. Currently it has a standard USGI combined flash hider and front sight unit, but the Mk14 program rifles have some combination of SEI gas lock mounted front sight (trident/fork or hooded) and either a Vortex or Surefire flash hider (depending on Mod 0 or 1 or in between).

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