Can I shoot through Deathtrap?

Solution 1:

Bullets do not go through Deathtrap. However, rockets and other things that explode on contact (glob gun shots for example) do go through deathtrap.

How I tested it:

1. I cleared an area of enemies and summoned Deathtrap.
2. I then positioned him between myself and a corrosion barrel. Close enough that even if I missed him due to Anarchy I couldn't hit the barrel.
3. I then unloaded several clips into him, aiming at the barrel on the other side of him.
4. The barrel didn't go off.
5. To double check that I wasn't mistaken in my aim; I waited for him to disappear and then shot once, blowing up the barrel.

Additionally, to try to rule out ricochets off of Deathtrap I performed another test:

1. I have 5 points in Close Enough (50% chance to ricochet)
2. I summoned DeathTrap and positioned him in front of me, with the barrel off to my side.
3. I unloaded several clips into him, aiming at different points and strafing to ensure that if I was ricocheting that it shouldn't have been able to miss.

I noticed that no ricochet trails were appearing on screen, and the barrel did not explode.

Solution 2:

In regards to it being a moving object like any other NPC. I recently was in fight for your life mode as Zero, and between Deathtrap and I was a grouping of baddies to be shooting at. I had the bore spec, so thought nothing of shooting through deathtrap, but no bullets went through, and damaged the ones behind deathtrap. Thus I died, and well yeah, bullets don't go through Deathtrap, no matter the circumstances.