I have a mid length from saber, and a 14.5 from bushmaster, and I can't get the gas tubes even started into the FSB on either one.  This is my first attempt at putting an ar together.  I thought the gas tube would just slide in.  I am scared to attack it with pliers or hammers because it looks like you could crimp it pretty easy.  Is there a secret?

On an unrelated note, my front sight tool won't fit between the ears of either FSB.  Is that unusual?

TIA for any suggestions you might have.

It might/might not just slide in (lube it up reall well first ).
You might have to push it in, but the amount of forced needed should not bend/break the tube.

That or your FSB is not made to specs and is too narrow.

To make you feel better I had trouble getting the gas tube out...
Aftermath

Edit: some editing.

I had one FSB where the tube was very tight going in, but most of them, it slides in with little or no effort.  Kinda like the women I've known