Thanks in advance ........

1) I want to remove an Oly FIRSH barrel nut (came with the FIRSH). It is about 1.25" in length and it the threaded nut that the FIRSH twists onto. It has the holes drilled in it (one of which you would slide the gas tube in if it were a 223). I didnt install it so I dont know how to remove it.

2) is this the olny thing attaching the barrel to the upper? In other words, if I remove it will there be something else?

3) Is the 9mm barrel that same exterior footprint as a 223 barrel? In other words, if I am able to get this FIRSH nut off do I just need a standard barrel nut to replace the item I am removing. In other words again- is there anything as a 9mm barrel nut?

Thanks again

you will need a bbl wrench that has pegs on it to remove the bbl nut but make sure you remove the gas tube first.

yes.

the firsh should work on the 9mm bbl.