Got a Real-World Weapon, Armor or Tactics Question? Mk. XXVII

[Kiero]

I'd say the rifle length is the deciding factor here - if you look at those pictures, the bayonet makes the carabine have the same reach with bayonet on as a musket would have.

That's exactly why sword-bayonets for riflemen were longer than the socketed bayonets those with muskets had. Because the rifle was shorter than the musket.