PSA 9mm AR uppers are hard to beat

TruthTellers · July 5, 2018, 12:40 PM

I had been planning on getting the parts to build a 9mm upper for some AR lowers I recently bought, but was hesitant when I started looking at the total price. Stripped upper, barrel, BCG, charging handle, delta ring and other barrel parts, muzzle device, and handguard were totaling out to nearly $500. Quite a bit for something that's not really a long range accuracy gun.

Found out last night Palmetto State Armory was having some killer sales and saw they had a 10.5" assembled upper with everything, MLok handguard too, for $320 and free shipping. The only downside is the muzzle threads are 1/2-36, not 1/2-28.

Bought it immediately. Don't see the sense in spending the time building an upper that costs more for something that will likely be just as accurate out to 75 yards with 9mm. For true rifle cartridges like .223, I can see the logic behind building that yourself, but for PCC uppers, I'm not.

Anybody disagree?

MagnumWill · July 5, 2018, 05:41 PM

I decided to start building a 9mm AR for HD, purely for the fact that if I have to fire a round without ear protection, I would prefer to have it set off 9 grains of powder, instead of 24.

I went with a Quarter Circle 10 upper and lower with Colt mags, as they were running a killer deal at the time ($180 for a blemish lower, $150 for blemish upper).

I've had nothing but good experiences with PSA, so I would give their 9mm's the same benefit of doubt. I would have gone PSA but I already had Colt SMG mags laying around that I want to use.

Chainsaw. · July 5, 2018, 10:04 PM

Nice to hear you good experience with PSA. I built a 9mm "pistol" last year, upper ended up pretty spendy, but then again I got a fairly swanky rail. All that in hind sight, yeah, I probably should have gone the route you did. Especially being I now have a $900+ build that mostly sits in my safe....ugg.

And about those colt mags, they just look RIGHT vs glock mags.

TruthTellers · July 6, 2018, 12:47 PM

Quote:

Originally Posted by MagnumWill

I decided to start building a 9mm AR for HD, purely for the fact that if I have to fire a round without ear protection, I would prefer to have it set off 9 grains of powder, instead of 24

This is one of the reasons I'm building a 9mm AR pistol. Mine is going to have the 10 inch barrel, which from chrony tests the velocity drops about 2% compared to a 16 inch barrel.

I just don't see why I'd want the extra length to get an extra 2% in velocity, not when I could slap a suppressor on the barrel that would bring it up to about 16 inches and reduce noise dramatically.

Also looking at getting a Fostech Echo binary trigger. Then I can have the closest thing to a submachine gun as the law will allow me.

9x19 · July 6, 2018, 07:11 PM

The law will allow you to have a genuine sub-gun... but I understand if your budget director won't.

TruthTellers · July 6, 2018, 08:50 PM

Quote:

Originally Posted by 9x19

The law will allow you to have a genuine sub-gun... but I understand if your budget director won't.

I'm my own budget director, but I'm not a drunken sailor either. I have another build I'm working on too, but it's a 5.56. I'd rather go cheap on the trigger for both, find out what groups they'll give me, and go from there. I can't put out $500 now on a Fostech, but in the future I can see myself doing it.

Midway has a lower parts kit sale right now and it includes the pistol grip and trigger for $42 and shipping while Brownells has a lower kit minus the trigger parts and grip for $22... really hard to justify buying a Fostech Echo right away.

If the next mass shooting involves a binary trigger, yeah I'll panic buy one... or three (and sell the other two on gunbroker for twice the price).

TruthTellers · July 8, 2018, 10:24 PM

I have an update on this that I just found out (after the upper has shipped of course.)

I was going to get a Stern Defense magazine adapter because my lowers are all standard lowers, not 9mm specific lowers. Turns out that with the PSA upper the Stern Defense won't work without a modification to the bolt.

Now my options are either to have Stern modify the bolt, which they offer to do, buy a 9mm specific lower, which costs the same as buying the Stern adapter, or cancel the order with PSA, which I would hate to do because they're basically giving a free MLok handguard away with this assembled upper.

stagpanther · July 9, 2018, 06:04 AM

I did my one blow-back AR--that was enough for me. One day when the market finally is ready, someone will make a "get real" pistol caliber AR with locking bolt.

9x19 · July 9, 2018, 07:33 AM

Quote:

Originally Posted by stagpanther

I did my one blow-back AR--that was enough for me. One day when the market finally is ready, someone will make a "get real" pistol caliber AR with locking bolt.

IIRC, you built a 10mm blow back... this guy has been doing locked breech ARs in 10mm and .45 (maybe others) for some time.

http://www.rmwxtreme.com/

I have three 9mm blow back ARs and they all run just fine.

Citadel99 · July 9, 2018, 07:54 AM

Quote:

Originally Posted by TruthTellers

I have an update on this that I just found out (after the upper has shipped of course.)

I was going to get a Stern Defense magazine adapter because my lowers are all standard lowers, not 9mm specific lowers. Turns out that with the PSA upper the Stern Defense won't work without a modification to the bolt.

Now my options are either to have Stern modify the bolt, which they offer to do, buy a 9mm specific lower, which costs the same as buying the Stern adapter, or cancel the order with PSA, which I would hate to do because they're basically giving a free MLok handguard away with this assembled upper.

I just bought a PSA 9mm upper and picked up the Stern Defense adapter for my SBR'd lower. I sent the bold in and they sent it back to me with no modifications and refunded me the money. Apparently PSA has changed their hybrid bolt and they don't need to mill it any more...

Mark

stagpanther · July 9, 2018, 08:11 AM

Quote:

Quote:
Originally Posted by stagpanther
I did my one blow-back AR--that was enough for me. One day when the market finally is ready, someone will make a "get real" pistol caliber AR with locking bolt.
IIRC, you built a 10mm blow back... this guy has been doing locked breech ARs in 10mm and .45 (maybe others) for some time.

http://www.rmwxtreme.com/

I have three 9mm blow back ARs and they all run just fine.

I think the 9mm blowbacks work OK only by virtue of being a relatively diminutive-powered cartridge--it's a flawed concept IMO--relying on carrier weight to chamber a cartridge and have that same weight flying around in the receiver while cycling. Just my biased opinion. I DO like extreme's 9 x 25 Dillon--that definitely has my attention--thanks for that. : ) Also noticed they make a hybrid 338 for the 10mm case--that too is very interesting--though I suspect that would have capacity/neck tension issues--the Dillon is pretty tricky.

Fishbed77 · July 9, 2018, 09:12 AM

Quote:

I think the 9mm blowbacks work OK only by virtue of being a relatively diminutive-powered cartridge--it's a flawed concept IMO--relying on carrier weight to chamber a cartridge and have that same weight flying around in the receiver while cycling.

It's a "flawed concept" that has worked extremely well for the vast majority of 9x19mm submachine guns over the last century.

stagpanther · July 9, 2018, 09:43 AM

Quote:

It's a "flawed concept" that has worked extremely well for the vast majority of 9x19mm submachine guns over the last century.

That's true--but few (if any) of those designs have been adapted from commercially available AR parts. Just my opinion--not willing to take the risk in an AR without a bolt lock-up (and better feed than Glock magazine). Have fun--enjoy, whatever. My opinion isn't going to change.

TruthTellers · July 9, 2018, 11:09 AM

Quote:

Originally Posted by Citadel99

I just bought a PSA 9mm upper and picked up the Stern Defense adapter for my SBR'd lower. I sent the bold in and they sent it back to me with no modifications and refunded me the money. Apparently PSA has changed their hybrid bolt and they don't need to mill it any more...

Mark

When did you buy this upper? I ordered mine this weekend...

Citadel99 · July 9, 2018, 11:30 AM

About a month and a half ago. The guys at Stern said it was the first one they had seen that was compliant.

Mark

TruthTellers · July 9, 2018, 12:58 PM

Quote:

Originally Posted by Citadel99

About a month and a half ago. The guys at Stern said it was the first one they had seen that was compliant.

Mark

Could you post the link to the upper you bought? I got the 10" with the "Hybrid G-9" bolt and that's one of the problem bolts with the Stern adapter. If you got the same style bolt as I will be getting, then I should be good to go.

Hopefully.

Citadel99 · July 9, 2018, 01:24 PM

This was the one...

https://palmettostatearmory.com/psa-...165448209.html

Looks like the same bolt. Even if it's not, it's cheap to mail it to Stern, they do it for next to nothing, and get it back to you quickly.

Fishbed77 · July 9, 2018, 01:56 PM

Quote:

That's true--but few (if any) of those designs have been adapted from commercially available AR parts. Just my opinion--not willing to take the risk in an AR without a bolt lock-up (and better feed than Glock magazine). Have fun--enjoy, whatever. My opinion isn't going to change.

That's why the bolt of a blowback 9mm AR has to have considerably more mass than a 5.56x45mm bolt carrier group. Colt figured this out many decades ago with the Colt SMG. Physics don't care about your opinions.

That said, who knows if the various commercial pistol-caliber AR manufacturers are putting as much thought into the weight of the bolt, buffer, and buffer spring as they should? Even if they don't, the the AR design is very forgiving in this respect, due to the buffer, massive buffer spring, and generous travel distance for the bolt in the buffer tube.

Most of the 9x19mm submachine guns over the years that have functioned on simple blowback have been designed and constructed in a much more questionable manner and of much more questionable materials than the AR. It is literally the simplest self-loading mode of operation there is.

.

bfoosh006 · July 18, 2018, 05:01 PM

Be sure to check the "over travel" of the bolt into the buffer tube... in context to the bolt catch.

You want about 3/16" of distance between the FULLY compressed BCG and the bolt catch.. any more than that and you risk breaking the bolt catch.

Also, you will find with a carbine length buffer tube.. the 9MM PCC can handle some very heavy buffer weights and heavy recoil springs.

My PSA Colt pattern's ( carbine stock ) 16"... "Linda Blair"like bark and blast was calmed down with a .308 Tubbs flatwire recoil spring and a 7.5ish oz buffer weight.
It now cycles like Winnie Pooh... steady and smooth.

July 5, 2018, 12:40 PM	#1
TruthTellers Senior Member Join Date: October 22, 2016 Posts: 3,888	PSA 9mm AR uppers are hard to beat I had been planning on getting the parts to build a 9mm upper for some AR lowers I recently bought, but was hesitant when I started looking at the total price. Stripped upper, barrel, BCG, charging handle, delta ring and other barrel parts, muzzle device, and handguard were totaling out to nearly $500. Quite a bit for something that's not really a long range accuracy gun. Found out last night Palmetto State Armory was having some killer sales and saw they had a 10.5" assembled upper with everything, MLok handguard too, for $320 and free shipping. The only downside is the muzzle threads are 1/2-36, not 1/2-28. Bought it immediately. Don't see the sense in spending the time building an upper that costs more for something that will likely be just as accurate out to 75 yards with 9mm. For true rifle cartridges like .223, I can see the logic behind building that yourself, but for PCC uppers, I'm not. Anybody disagree? __________________ "We always think there's gonna be more time... then it runs out."

July 5, 2018, 05:41 PM	#2
MagnumWill Senior Member Join Date: March 18, 2009 Location: Central Colorado Posts: 1,001	I decided to start building a 9mm AR for HD, purely for the fact that if I have to fire a round without ear protection, I would prefer to have it set off 9 grains of powder, instead of 24. I went with a Quarter Circle 10 upper and lower with Colt mags, as they were running a killer deal at the time ($180 for a blemish lower, $150 for blemish upper). I've had nothing but good experiences with PSA, so I would give their 9mm's the same benefit of doubt. I would have gone PSA but I already had Colt SMG mags laying around that I want to use. __________________ Those who hammer their swords into plow shares will plow for those who didn't...

July 5, 2018, 10:04 PM	#3
Chainsaw. Senior Member Join Date: September 12, 2015 Location: Issaquah WA. Its a dry rain. Posts: 1,774	Nice to hear you good experience with PSA. I built a 9mm "pistol" last year, upper ended up pretty spendy, but then again I got a fairly swanky rail. All that in hind sight, yeah, I probably should have gone the route you did. Especially being I now have a $900+ build that mostly sits in my safe....ugg. And about those colt mags, they just look RIGHT vs glock mags. __________________ Just shoot the damn thing.

July 6, 2018, 07:11 PM	#5
9x19 Senior Member Join Date: October 15, 1998 Location: Sherman, TX USA Posts: 3,750	The law will allow you to have a genuine sub-gun... but I understand if your budget director won't. __________________ Make mine lean, mean, and 9x19!

July 8, 2018, 10:24 PM	#7
TruthTellers Senior Member Join Date: October 22, 2016 Posts: 3,888	I have an update on this that I just found out (after the upper has shipped of course.) I was going to get a Stern Defense magazine adapter because my lowers are all standard lowers, not 9mm specific lowers. Turns out that with the PSA upper the Stern Defense won't work without a modification to the bolt. Now my options are either to have Stern modify the bolt, which they offer to do, buy a 9mm specific lower, which costs the same as buying the Stern adapter, or cancel the order with PSA, which I would hate to do because they're basically giving a free MLok handguard away with this assembled upper. __________________ "We always think there's gonna be more time... then it runs out."

July 9, 2018, 06:04 AM	#8
stagpanther Senior Member Join Date: March 2, 2014 Posts: 11,789	I did my one blow-back AR--that was enough for me. One day when the market finally is ready, someone will make a "get real" pistol caliber AR with locking bolt. __________________ "Everyone speaks gun."--Robert O'Neill *I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk!*

July 9, 2018, 11:30 AM	#15
Citadel99 Member Join Date: February 13, 2002 Location: Austin, TX Posts: 83	About a month and a half ago. The guys at Stern said it was the first one they had seen that was compliant. Mark

July 9, 2018, 01:24 PM	#17
Citadel99 Member Join Date: February 13, 2002 Location: Austin, TX Posts: 83	This was the one... https://palmettostatearmory.com/psa-...165448209.html Looks like the same bolt. Even if it's not, it's cheap to mail it to Stern, they do it for next to nothing, and get it back to you quickly.

July 18, 2018, 05:01 PM	#19
bfoosh006 Senior Member Join Date: February 17, 2009 Posts: 1,089	Be sure to check the "over travel" of the bolt into the buffer tube... in context to the bolt catch. You want about 3/16" of distance between the FULLY compressed BCG and the bolt catch.. any more than that and you risk breaking the bolt catch. Also, you will find with a carbine length buffer tube.. the 9MM PCC can handle some very heavy buffer weights and heavy recoil springs. My PSA Colt pattern's ( carbine stock ) 16"... "Linda Blair"like bark and blast was calmed down with a .308 Tubbs flatwire recoil spring and a 7.5ish oz buffer weight. It now cycles like Winnie Pooh... steady and smooth.