I am looking for some assistance building an AR9 under $400. Can my Maryland shooter folks help me out.
Not sure it can be done and have it run reliably.
Example, you can find AR-15 lowers for $50 in MD. But AR-9 dedicated lowers are going to be hard to find for less than $100. Or you are spending $50-100 on a magwell adapter. BCG can be bad for $60 for an AR-15, but an AR-9 you are going to be hard pressed to find one under $100 and more likely $150+
It isn’t an impossible task, but you are going to spend a ton of time finding sales and accumulating parts and often they don’t run quite right the first time, which means investing in a replacement part of two to get it tweaked and running right.
I’d budget $500 as a minimum budget AR-9 and figure reasonable, quick and running right may be more like $600-800.
Don't go cheap on AR-9 parts. I broke 2 cheaper BCGs before I bought a better one that has not failed. Now I have 2 separate uppers for difference kinds of competition.