Getting spikes every ~0.5 seconds periodically

http://i.imgur.com/BTBMVd9.png

Image should say it all but here's the code snippet (http://i.imgur.com/obRDgel.png), I know there is no lock on _Rundels (I thought it might be waiting for a lock so I removed it for testing)

I don't know why, if it's copying over a list every frame, it takes 419ms one time and not the others. Spiking in unity is ridiculous from my experience, everything that can be moved to a thread is because of the spikes, but I don't know why making a list of 2 items should take that long(no, _Rundels isn't locked anywhere else).

This issue happens with everything, every project I make I come to a point where an 'if' statement, making a new list or making a new thread taking 500ms causes me to quit. Could anyone point me in the right direction, explain to me why a new list being made every frame takes 0.7ms every frame except every half second where my screen locks up because it's taking 419ms. Is there a function in Unity like "try" but puts a time limit on the function and just exits out if it goes over/tries again next frame?

Does Unity randomly stutter on some functions or do I need to continue looking through my code for a few more weeks?