Target Acquisition and Sneakiness in Bolt Action

Something that irks me slightly about Bolt Action is that there's no real mechanic to reflect battlefield concealment or stalking. If you can draw a line of sight between one model and another, then they can see each other plain as day. Cover helps your troops to avoid being hit when fired at, but it does nothing to impede target acquisition in the first place.

I'd like to propose a couple of house rules:

Target Acquisition:

Before one unit can shoot at another, they first have to acquire the target by passing an Orders Test (though if they fail, they don't suffer the usual consequences of failure, they just fail to see the target).

It would be modified as follows:

• Per Pin marker, (-1)
• Acquiring unit is Down, (-1)
• Concealment (see below)
• Target is Down (-2)
• If the target moved more than 3" within the last turn (+2)
• If the target moved less than 3" (+1)
• If a friendly unit in line of sight of the acquirer shot at the target within the last turn (+1).
• If the target shot at another unit within the last turn (+1)
• If the target shot at the acquiring unit at any time from its current position (+2)

Once a unit has acquired another, they maintain acquisition until either they or the target moves out of line of sight.

Concealment:

A unit in line of sight from another, but not yet acquired, can declare itself to be attempting concealment.

Concealment has no effect except to hinder acquisition by an enemy unit.

Roll 1d3 to determine the penalty to other units' acquisition:

• Inexperienced troops are at -2
• Regular troops are at -1
• Veteran troops at -0.

The roll is further modified as follows:

• If more than 3" from any cover, -2
• If less than 3" from cover, but still in the open, -1
• If touching cover, or if the unit is partially in cover, -0
• If the entire unit is in cover (but still in line of sight), +1
• Small vehicle or gun (e.g Bren carrier, jeep, 6 pdr) -1
• Medium vehicle or gun (e.g. truck, half-track, PaK 40) -2
• Large vehicle or gun (tank, 17 pdr, 88mm) -3.

Regardless of penalties, the minimum score is zero — no matter how incompetent your troops, they're not going to become more obvious by trying to hide.

Infantry and man-packed crew weapons can still move up to 3" while attempting concealment, but it will make it easier for enemies to spot you (see above). Vehicles of any kind must remain stationary to be concealed.

Concealment is lost as soon as the concealed unit opens fire, and may not be regained without moving to a new position at least one Run move away.

A veteran infantry unit, Down, in cover, and concealed is going to be quite hard to spot, but as soon as they open fire they'll lose the benefit of their sneakiness.