The following is the 'Octamodem' Bolt with eight mode states. Space Marine carry around 180 of these bolts as part of their standard kit on tactical operations.
Mode 0 (Storage)
Can only be armed with correct coded signal from authorised Bolter. The Bolter can only authorise if it receives the correct activation commands from is designated covenet and is attached via a live feed and confirmation of vital life signs has been confirmed. This is a double safety measure as both Bolter and ammo is rendered inactive unless a Marine is present.
Mode 1 (HEAT: High Explosive Anti Tank)
Kicker - Enabled/ Gyrojet array - Enabled/ PIBD - Enabled/ Proximity fuse - Disabled/ Auto destruct - Enabled.
At short range (up to 50m) the bolt defaults to mode 1 until it picks up sufficient speed to cause impact damage through kinetic energy, it then takes on a programmed intent of the shooter if different from mode 1.
The bolt detonates as a shaped charge on contact and is effective against heavy armours acting as an RPG (rocket propelled grenade). However they are ineffective against 'electric armours'.
HEAT Performance (approx)
Mode 1 can punch though 4" (100mm) of RHA (Rolled Homogeneous Armour), 2' (600mm) of pine logs, 32" (800mm) of concrete block, 6" (150mm) of reinforced concrete, 4' (1200mm) of sand bags, around 2" (50mm) of base ceraforms. All these figure are consistent over the entire range of the weapon, and max powered range of 1km/ 1000m/ 3,280 feet.
Vs Modern armour
The bolt would slice through most APC armour, including the M113's 12-38mm aluminium armour (aluminium tends to vaporise when hit with HEAT rounds) and the M2/M3 Bradley even with urban armour upgrades. The Bolt will not penetrate the main battle tank armour such as Chobham Armour found on the Challenger 2 and Abrams M1 (guesstimate equivalent of 24" of RHA on main facings). However, the Bolt would destroy tracks, hatches, and other vulnerable areas so a Marine would gain access (disable, close, access, finish with mode 2 to interior).