Weapons are able to ignore line of fire if lag is involved I.E Hitting blocks inside your ship without hitting blocks in front of these blocks.
Example: http://i.imgur.com/q2nQAUO.jpg
As you can see in this picture there is damage deep within the ship even though no damage has been done to the external hull something that should be impossible since weapons work off of line of fire.
I used cannons to test this affect but missiles can also be subject to "spawning" inside your ship if enough lag is involved so can beam weapons.
Steps to reproduce:
Spawn a ship (preferably a large one)
Pilot that ship and spawn another ship to fight
Simply let the mob fire on you while you move around
You will find that damage is being done deep within your ship with no entry point being made.
This is mainly due to lag so the more of it you have the more likely the bullet will bug out and spawn inside your ship or detonate deep within the hull.
Please note here larger sector size may be partly responsible as the larger the sector the less accurate the math that governs position is.
Test conducted with 10KM sector size 2KM sector size would yield near same results due to testing with 1 million block ships.