Galvanic Weapons are a type of weapon used by the Adeptus Mechanicus. These weapons fire electro-galvanically driven projectiles that can damage and pierce both enemy infantry and armor alike.
Galvanic weapons runs on Galvanic cells obviously. A galvanic cell, or voltaic cell, is an electrochemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. In layman's talk, they run on a battery. As this cell only generates the physical power, similar to gunpowder, Galvanic weapons must also fire some form of projectile (sometimes bullet, sometimes flechettes, whatever you want really). So just like a bullet only instead of a gunpowder there's a battery.
Given that they fire a projectile with electro-magnetic energy, they're basically an Imperial railgun, though obviously less powerful due to using a battery instead of a reactor. This also means this is one of the few weapons that have an Imperial variant that is less Grimdark than its Xenos counterpart and for once the Ad Mech aren't the ones who will get radiation poisoning.
As with most AdMech weapons, Galvanic weapons have a pretty cool steampunk-sheen to it. Making it both classy and nice to look at.
The Galvanic Caster is a type of galvanic weapon used by the Adeptus Mechanicus. Wielded by Secutarii Peltasts, this electromagnetically driven projectile weapon is akin to a combi-weapon, in that it is a galvanic shotgun paired with what is effectively a Grenade Launcher
With its main weapon mechanism, it is able to fire rapid bursts of low velocity razor-edged flechettes, or with its secondary discharger, attack concealed targets with retina-burning ignis charges. Some of these weapons are upgraded with a high-intensity capacitor which compresses the galvanic charge to fire an armor-piercing inert slug at the supersonic velocity all lethal slugs are shot at. This complex but flexible weapon allows the Peltasts to engage a wide variety of enemy targets.
For some reason, Skitarii Rangers can't use this, even though it would make a great special weapon for them in for both aesthetic and logistical reasons.
The middle step-child of the Galvanic family. The Galvanic Carbine is the 'rifle' of the Galvanic weapons and offers a fine balance between the Galvanic Rifle and the Galvanic Caster. The weapon shares the same revolver-style ammunition casing as the Galvanic Rifle, making it simple to repair and maintain at the cost of a slower reload.
As a carbine, it has an inferior range than the Galvanic Rifle, but it is much easier to handle. Makes sense, given that the primary users of these weapons are the Serberys Raiders, who must both fire their gun whilst riding a mechanical steampunk
horse greyhound. Due to their ease of handling and a rather basic maintenance in design, the Carbine is actually considered a standard-issue weapon, not a specialised weapon for the AdMech.
Due to their augmentations, it is not surprising to see a Raider snipe important individuals with the Galvanic Carbine whilst on horseback.
The sniper rifle of the Galvanic family tree.
Galvanic Rifles are a type of weapon used by Adeptus Mechanicus Skitarii. The favored weapon of Skitarii Rangers, it is modeled after the flintlock guns of Mars' past, though in terms of design it pulls more from the Lee Enfield. The current model of the weapon, known as the Mk IV Arkhan, are exquisitely hand-crafted but no less deadly. These weapons fire specialized bullet over long distances that causes all potential energy of the target to burn out in a killing blast of electric force. How it burns the potential energy of the target with a bullet, is like many things, never explained. How the army they're in doesn't die from so much energy being released is also inexplicable. How none of the other Galvanic weapons do this, is likewise inexplicable.