I don't really understand what you mean by that. To clarify, the bayonets are being used as bayonets, attached to a rifle. However, attaching a bayonet doesn't actually change the melee damage of the rifle. I just did a quick test, and the game is just applying the normal bashing damage of the rifle, as if there is no attachment. Reach attacks are possible with the sword bayonet, but the it is still just using the rifle's unmodified bash damage.