Hello,

New here and new to AR9 builds. I have a few questions if anyone could help me out it would be much appreciated.

UPPER/LOWER: Gibbz G9
BCG: Gibbz G9 (16.8oz) 9mm BCG
BARREL: BA 5.5"
SUPRESSOR: SiCo Omega9K Or Rugged Obsidian9 (short config)

My question and confusion is with the buffer weight and spring I should use as I will be running this suppressed mainly if not entirely. I'd like to run 115,124,147s.

Gibbz says their BCG is heavier than most at 16.8oz and to use a Carbine Buffer (3ish oz) and carbine spring. I'm not sure if anyone would advise otherwise.

Anyone offer any advice?

For what it's worth, I run a JP SCS and JP BCG my AR9 runs flawlessly with every kind of ammo I have tried 115, 124 and 147.  I now only stock 147 but that is because I run a silencer and 147s are subsonic out of my 4.5 inch barrel.

Good to know. What is the physical weight of the JP BCG?

Gibbz says they engineered theirs heavier at 16.8oz intentional to be able to run standard H 3oz to 3.4oz buffers.

Which JP SCS specifically? Normal, Enhanced or Short Stroke?

Don't know the weight, don't have a scale that will measure it but it is the standard 9mm SCS and standard spring.

Just for comparison, my stock 10.5 inch PSA 9mm AR uses a 5 ounce buffer, carbine spring and the bolt weighs 14.1 oz.  
It shoots 115 -147 both light and hot loads without a single failure so far.