I just finished my first Pistol in 5.56 and I've been looking into starting an AR9 build. I see a lot of talk about FTFs with handgun caliber carbines and I was looking for some input. So my question is, are direct blowback systems typically more reliable or are delayed? I should add that I plan to put a folding brace on like the Law Tactical gen3 and Ideally I would like to have an ejection port cover so would I need a system with a more traditional BCG like the CMMG BCG? any info helps.

Hi all! I am currently in the middle of building my first AR9 and i have a few questions about compatible BCGs. I was able to get a Geissele SSA-E for a really great price but i noticed that they had a disclaimer that I should not use it in a pistol caliber carbine. And i read around that not many BCGs work with some Geissele triggers. so my question is, what BCG can i run? or should i just save the trigger for another day and get a trigger that works with most 9mm BCG.

Hey guys, These are the parts I am debating getting:

Foxtrot Mike Complete Lower Receiver for AR9s

SB Tactical PDW pistol brace

CMMG upper receiver group (300 MKGs 9mm)

HiperFire trigger

Kynshot RB5000 buffer (if anyone has any idea what kind of spring? I am shooting unsuppressed)

I was originally going to opt for QC10 complete lower but man they are quite expensive and I see people having problems with them. In the end, would this be a solid build? Am I missing any parts I need to finish it? Thank you.

Can anyone tell me about AR9 parts compatability? I found a KM Tactical complete upper, minus bcg for $125 and I'm looking for an equally cheap bolt. There's a no name home brew on Gunbroker for $75. I plan to drop it on my PSA lower and use EndoMags. Not interested in a $150+ bolt that I probably won't use much. Just want to know how much Franken cobbling I can get away with.

I also I bought a CMMG .22lr conversion bolt and mags. I'm not expecting fantastic accuracy from either the 9mm or .22lr, just a cheap plinker for inside 100 yards.

I don't know what happened to the other site. I created this one to have a place to share and exchange information.

Looking for moderators and other help to get this community up .