9mm AR Upper Questions

[FOOMAN]

I know I could do some research but guys on here are usually quick to respond cause I have see a few pics of 9mm AR uppers. I have a standard lower pistol receiver already built. I also have a standard upper receiver. I think the only thing I need is a 9mm barrel and BCG. Is that right? I have a hand guard also. What length barrel? I will attach my Mystic. Will the standard AR upper receiver work? Thanks for the help.

 

[Laxguy59]

Well I would say any barrel length you please, but shorter is always better. I have a 5" barrel, but would rather have a 5.5" because I don't even clear the shortest pistol rails on the market. My Osprey needs the XL piston to thread on to the barrel since It's not round and wont recess into the rails. It's like 1mm away from the shoulder

You wont need a gas tube or block, just BCG and barrel.

You will also need a magwell block or a dedicated lower.

PrON!

yes that's a black santa, cuz he's tactical.

 

[FOOMAN]

Nice. Thank you for the info.

 

[sovietak474u]

You will love the suppressed 9mm AR. I love mine. Very quiet.

 

[Laxguy59]

http://www.theoutdoorstrader.com/threads/187663-AR-9mm-PISTOL?highlight=ramroddoc+9mm

A good thread by RamRodDoc, that dude knows his stuff.

 

[vinhtvu2]

Dang, this just made it on my want list!

So there's no gas block / tube involved?? How does that work?

 

[Laxguy59]

Dang, this just made it on my want list!

So there's no gas block / tube involved?? How does that work?

Direct Blowback. I'm not totally sure of the science, but because of that the longer barrels keep pressure higher longer leading to more port pop, therefore a short barrel can reduce noise at the port.

It's a very easy AR to put together.

ONly negative is that it is a bit dirty due to the action type, but Hi points and Beretta cx4 carbines are blowback as well.

the mp5 is the delayed roller action

and Ron Williams Extreme makes a DI 9mm which uses a standard AR-15 Bolt carrier with a bodified bolt. but the upper is like $700 alone.

 

[sovietak474u]

Direct Blowback. I'm not totally sure of the science, but because of that the longer barrels keep pressure higher longer leading to more port pop, therefore a short barrel can reduce noise at the port.

It's a very easy AR to put together.

ONly negative is that it is a bit dirty due to the action type, but Hi points and Beretta cx4 carbines are blowback as well.

the mp5 is the delayed roller action

and Ron Williams Extreme makes a DI 9mm which uses a standard AR-15 Bolt carrier with a bodified bolt. but the upper is like $700 alone.

I was surprised at how little port pop I had out of my AR-15 9mm. My scorpion has more port pop than the AR does.

 

[Laxguy59]

I was surprised at how little port pop I had out of my AR-15 9mm. My scorpion has more port pop than the AR does.

I think it's one of those things people complain about who have never owned one. There is so much *****ing about 9mm AR's on the web, I friggen love mine.

 

[opps]

You need the 9mm buffer and short dust cover.
Top insert mag well is better. Lower insert with hex key can split the lower if over tightened.