A rank and file clarification...

Forgive me if I've overlooked this, but, is there a maximum number of models you may have in each rank? Example: Could I run a unit of 60 gnobblars, with trapper upgrade, 60 models wide and 1 model deep? I know this may sound silly, but I really am working on something big here ...

no there is no limit, and did it.... was hilarious!!!!!

but, not very effective.

Was thinking of running 2-3 units of gnobbo trappers 60 strong and placing them 60x1 in 3 rows one inch apart... Then behind it sits my newly possible ogre gun line... Looking at a 2600 to 3000 point game... Thanks for the clarification btw.

Would the trapper dangerous terrain take place in the event of an overrun?

The trappers become obliterated and suddenly the unit that destroys them clashes into the next unit of trappers that was 1'' away.

How about the same scenario except when pursuing?

Those are considered new "Charges" so yes they would need to make Dangerous Terrain checks.

Problem is of course you can't shoot as something that's in combat. So they crash into the first line, obliterate it, and you need to put the next line 13" away or they'll overrun into it and be safe from shooting.

I think I'd prefer 3 sabretusks and multiple small 10-gnob units to try to run interference.

Yep, once they hit your first line, if they overrun You are basically picking your nose for a couple turns.

Thats also a lot of points to be giving your opponents for killing 1/6th of their unit.  Im currently trying to decide if 50 points is worth it, let alone 435.  I like the gun line though.

how does the step up rule even work with that? Can your opponent even kill more then 5-7 gnoblars a turn?

You can definitely kill more models than you're in base contact with, just as you can attack with more models than are in base contact. And I would be surprised in this situation if the opponent didn't get several units into contact, and was doling out dozens of kills every turn. I would expect overruns (rather than pursuit) a good fraction of the time, put it that way.