School me on go to 9mm AR parts

**Vegas** · 06-16-18, 02:14

Hey all,

Been thinking about a 9mm build for a while and finally ordered a New Frontier Armory C-5 lower (accepts MP-5 magazines). I'll be adding their upper receiver for compatibility with the mags but after that, I don't know squat. Some I am wondering what are the go to parts as far BCG, buffer, spring, receiver extension and barrel? The build will be a pistol configuration with either a SBA3 or Tail Hook Mod 1.

C5LOWER.jpg

Thanks in advance.

**Smokin338** · 06-18-18, 02:49

BCG - JP rifles has some of the best, second is any that copy their style... NO psa 1's period
buffer - dedicated 9mm extended buffer (7.5 oz minimum)
spring - 308 spring works good, more money XP or wolf
receiver extension - any mil-spec tube will work
barrel - Ballistic Advantage makes some good ones

**Vegas** · 06-23-18, 14:48

Originally Posted by Smokin338

BCG - JP rifles has some of the best, second is any that copy their style... NO psa 1's period
buffer - dedicated 9mm extended buffer (7.5 oz minimum)
spring - 308 spring works good, more money XP or wolf
receiver extension - any mil-spec tube will work
barrel - Ballistic Advantage makes some good ones

Thanks. I am trying to figure out what barrel length to go for. I don't currently own a suppressor for 9mm but it could happen in the future so may opt for something that helps with subsonics.

**medicman816** · 06-23-18, 21:08

I would keep it less than 5.5" for subsonic use. Suppressed 9mm ar is all kinds of fun.

**Warhawk** · 06-23-18, 22:05

I recently went through this and settled on the Foxtrot Mike setup, or FM Products as they are called. Check Primary Arms and Brownells. They use Glock magazines, but I understand a Colt magazine version is in work. I stuck with a 16” carbine, b7t they are also available with 8.5 and 10.5 inch barrels. They use a unique side charging system, and a very nice bolt hold open. They make billet receivers and a polymer receiver with metal inserts. I went with the billet receiver. I’ve got everything here except the receiver, which should be in early next week.

**Smokin338** · 06-24-18, 00:12

Originally Posted by Vegas

Thanks. I am trying to figure out what barrel length to go for. I don't currently own a suppressor for 9mm but it could happen in the future so may opt for something that helps with subsonics.

8-8.5" seems to hit the spot just right...

**Tortuga** · 07-01-18, 18:52

Originally Posted by Warhawk

I recently went through this and settled on the Foxtrot Mike setup.

Ditto on the 16" FM upper. I just got mine back from Cerakote. The whole thing started with an EDC glock lower that fell in my lap. It was supposed to be a budget setup until I installed a hiperfire Eclipse, TACCOM 3-stage buffer, and BAD safety.
I'm already eying a quarter circle ten lower with TACCOM ultralight weight upper.

**Vegas** · 07-01-18, 19:03

From what I have gleaned elsewhere, the FM stuff is decent but temperamental with the NFA C5 lower. I’ll stick with the NFA assembled upper (just the upper, not group) as they are local and I can get support.

**blade_68** · 07-01-18, 20:41

A heavy A5 buffer works well for me with standard receiver extension (buffer tube) that's with my colt magwell one and 5.5 in barrel suppressed. The longer length keeps 9mm brass out on hammer area and shortens bolt travel. I will second that JP's 9mm bolt works well.