There are normal swords in the 40K universe too. I wouldn't mind a chain sword either but that doesn't seem to fit the role of an officer very well.
If anything the LC's on the GM squads should get a bolt pistol. Normal bolter weapons can't be used by normal humans and are actually illegal for them to use.
There are special augmented bolters though for them to use.
Also the reason I think the LG has a bionic arm.
So they could model him with a bolter. ^^
Like other Space Marine weaponry, Astartes Bolters are designed to be handled by their superhuman physique. The weight of each Godwyn Pattern Bolter means that most normal humans cannot handle the weapon comfortably without the aid of a supporting brace and even the weapon's handgrips are too large for a mortal to grasp without assistance. However, even if a mortal were to fire the Bolter, the resulting recoil would most likely rip his or her arm from its socket. It is illegal within the Imperium for a non-Astartes to wield an Astartes Bolter, which is one reason why the weapons are genetically coded so that only a Space Marine can fire them. An Imperial citizen caught in unauthorised possession of a Bolter or even of just a bolt can be harshly sentenced by the Adeptus Arbites. However, some Bolter patterns like the Godwyn-De'az or Locke patterns are specifically built to be wielded by unaugmented humans, and the weapon is sometimes favoured by officers of the Imperial Guard and members of the Adeptus Arbites who require a weapon with more stopping power.
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