My searching sucks

I have a 80% that I will be finishing and it will be for a pistol build.
The SSE is clear and it is recommended to have  Pistol engrave on I
to prevent a Over zealous LE thinking its a illegal SBR.


But the questions are
Does it have to have  a serial make and model too

after 2015


Can I use a longer than 7.5 inch barrel

TIA

I went on calguns looking for threads but failed

You do not have to have "pistol" stamped on it. Mine don't, I have an AR and a Draco and neither have pistol stamped on them. If you make it out of an 80% then you don't need serial number. I have a 7.5" upper but I think I'm gonna build an 10.5" next, so yeah you can go longer.

http://wiki.calgunsfoundation.org/FAQ#Does_my_homemade_firearm_need_a_serial_number.3F

Nothing needs to be stamped but its probably a good idea to put info on it just incase it comes up missing.  I would never own an AR pistol but if I did it would be 10.5". An adjustable gas block is a plus if yours is over gased. Mine was way under gassed (I mean my buddies) and needed the gas post drilled out. Once I drilled it out to 3/32" for him it ran perfect. It wont run steel worth a darn. I'm thinking about drilling it out to 1/8 and seeing if it works better for him. Its a lot easier to add an adjustable gas block then it is filling the hole.