Psycannon bolts
The bolt weapon carried by the Inquisitor has a magazine of psychically impregnated psycannon bolts. These vary in calibre from bolt pistol size to storm bolter shells, though their potency is remarkable in all cases. A bolt weapon (storm bolter, bolter, combi-bolter or bolt pistol) with this upgrade counts as AP4. Only Armour saves may be taken against psycannon bolts — Invulnerable saves may not be taken.