Raycast and Layer Masks

Back again, more problems :)

After completing and ironing out all the problems with making a collider based projectile and handling the damage across game objects, I realized as so many do. Fast moving collisions don't work. Kinda wish I was warned, but it lead to some extremely useful knowledge so I'm happy for the experience.

Moving along, I started to learn about ray casting. But I have some questions about it, and how to apply layer masking to it. Heres my code first.

     var hit = (Physics.Raycast (transform.position, target, range));
     if (hit != null) {
          var testhit = hit.GetComponent(test);
               if (testhit != null) {
               print("Companion Cube in sight!");
               }
     }
 

Now as you can plainly see... I haven't gotten far. I was using code who's sintax I cannot seem to fathom using the lovingly emblished reference material. I thought I was applying a layer mask to variable testhit. The layer I was trying to restrict to was test. The only object in my test environment that has the layer test is a cube named 'Companion Cube'. But it was sorta a failure on the debug check. Kept spitting the same mumbo jumbo that every programmer I know hates. Error code: Something~in~greek

So moving along. What I need help with is the sintax involved. If you could show me my trouble spots using the same variables I used. (When people use cookie cutter expamples I get very lost as to what is a function/var/expression/blackmagic etc.)

Also, layer masks seem to be Exclusive only from what I've read (Which really makes me feel my code is fragged) is there a way to write it so that I don't have to isolate the layer mask as a variable and invert it with the whole var = ~var expression?

I'm fairly confident that once I understand the layer mask sintax, so I can restrict the contact of my ray-caster unity will stop having a hissy-cow about unexpected Boolean nonsense.

Next question I'm fairly sure is in-depth. Raycasting appears to cast the ray as far as the distance its marked for. Returning everything it bashes into (Maybe I'm totally wrong there, Sorry if I am please set me straight). But I don't want all my bullets to be piercing. I'd like to be able to restrict the selection to the first, second, third, All, objects it collides with, in order. This way I can add target's pierced. Or all. Or simply stop on the first target. Is there a way to isolate and restrict this or pick it apart as usable information?

On the flip side, if ray-casts don't push beyond the first collision, how am I to accomplish piercing bullets?

I know this is a lot of questions honestly, but they are all the same two subjects in the heading, and I feel splitting all this information up would cause me to lose sight of the concept as a whole. Thanks for reading if you got this far and haven't given up on me!