Before you do something as foolish as shoot Sectopods with a Laser Pistol, let's do some math:
Laser Pistol base damage = 46
... with TFTD damage formula the range is 23 to 69
... Sectopod takes 150% from lasers, so it increases to 35-104
However, the armour of Sectopod looks like this:
- front armour: 145 (i.e. cannot take damage from laser pistol)
- side armour: 130 (cannot take damage)
- rear armour: 100 (can theoretically take damage, but maximum 4 per hit)... the chance to do any damage is 4/70=5.7% and with average damage being 2.5 and health of 96, you'll need to hit him approximately 674-times... good luck with that
- under armour: 90 ... using same math you would need to hit him only 192-times
but I don't really see a Sectopod flying in the air so that you can hit him from below...