PCC lower recommendations

[Alibiiv]

I posted this thread under a different forum, then I figured out it was in the wrong forum. I did some searching on the forum, and the only thread that I could find was from 2020. This guy wanted to build a .40 S&W. I am looking to build a PCC in 9mm.. I am looking for suggestions for buying a lower. This is going to be for home defense and playing at the range. Accuracy and functioning are part of this build. I presently have a Ruger PCC in 9mm. The rifle shoots and functions fine, I am just more familiar with the AR platform. The Ruger is shooting 4-5 inch groups at 100 yards with the right ammunition. More than enough to play with shooting steel. Presently there is a scope on this rifle just to see what it would do. I definitely want a 9mm just for the practicality of the cost of ammunition. The 9mm ammunition is quite inexpensive to purchase, however I have components to make 9mm if I have to. I do not know that much about 9mm lower, I believe they are blow back operated. It would be great if the lower were capable of holding Glock stick magazines as I have a few of them, however this certainly is not a deal breaker if the Glock sticks do not fit. I am asking for any recommendations about what to buy and where to buy the parts. I would not be opposed to purchasing a complete lower if a package would be a better deal. I know that I can buy a complete rifle, I just think it would be great to put together a Lego gun. I live in a left wing, liberal, deep blue state of corruption!! The east coast version of California!! I have until September of 2026 to put this together after this date I can no longer purchase anything or own anything (purchased after 9/26) that is AR or resembles anything AR. Thank you for any help and any recommendations.

 

[RWE]

I have always wanted an MP5, may still do it someday but I have two Full Stop issues - no Last Round Bolt Hold Open (LRBHO) and mags don't drop free. No go.

The 9mm PCC has become one of my favorite range and game guns for what we call "outlaw" matches - similar to IDPA, USPSA, etc. Handgun and carbine matches. 1,000's of rounds, love PCC. Cheaper and funer.

They are blow back and recoil tuning is for another post or PM.

I started with a 16" PSA PCC Rifle (for the carbine versions of our matches) and it is great, mags shoot out with authority, but... no LRBHO. Never had a single problem with that set up. As time passed and thoughts of the MP5 lingered, I moved to an AR Pistol format PCC. I played with some 10" but started at 8" and then 5", both suppressed. Oh my... so fun, quiet, fun, and even more quiet fun. Trying to decide between them but why decide??? Oh, the 16" sits in the safe...

I have two brands of lowers and have used a half dozen others. I also took time and studied pretty thoroughly and it can become a deep rabbit hole for sure. I built a PCC in AR Pistol with the AERO EPC9 upper and lower receivers. Highly recommend these having used and handled a few, seen others perform in matches. That said, whatever you get, I would tell you to go with upper/lower from same manufacturer. Tolerance stacking, blah, blah...

But of all of them, I recommend and see less (no) issues with tuned EPCs. I also love a buddies CMMG too.

Other recommendations - pick one mag brand and tune the LRBHO to that mag/follower. I have a few brands, recommend Glock or MagPul Glock pattern mags.

You mentioned optics, I use Primary Arms GLX 1x Prism, green, mounted high for heads up and over the light. Etched reticle, wakes up when you pick it up, good (not blue) glass, tough/solid built, good warranty, etc. Optics are personal, this is my choice.

Light - have streamlights and surefires but for these I added a Holosun P.ID light/laser. Designed for handguns (??huge) but I love them for this use and set them at 12 o'clock on the end of the handguard, just overhanging. You can use the light/laser individually or in combo. Great at night matches to 75-80 yards (farthest I tried at night).

Search the googles for "blowback9" and check out his website. If you have a bunch of questions, maybe buy him a coffee (he has a link) and ask questions, he responds! Has great testing data and other links to good info.

Good luck and have fun! Feel free to PM.

 

[Alibiiv]

I have always wanted an MP5, may still do it someday but I have two Full Stop issues - no Last Round Bolt Hold Open (LRBHO) and mags don't drop free. No go.

The 9mm PCC has become one of my favorite range and game guns for what we call "outlaw" matches - similar to IDPA, USPSA, etc. Handgun and carbine matches. 1,000's of rounds, love PCC. Cheaper and funer.

They are blow back and recoil tuning is for another post or PM.

I started with a 16" PSA PCC Rifle (for the carbine versions of our matches) and it is great, mags shoot out with authority, but... no LRBHO. Never had a single problem with that set up. As time passed and thoughts of the MP5 lingered, I moved to an AR Pistol format PCC. I played with some 10" but started at 8" and then 5", both suppressed. Oh my... so fun, quiet, fun, and even more quiet fun. Trying to decide between them but why decide??? Oh, the 16" sits in the safe...

I have two brands of lowers and have used a half dozen others. I also took time and studied pretty thoroughly and it can become a deep rabbit hole for sure. I built a PCC in AR Pistol with the AERO EPC9 upper and lower receivers. Highly recommend these having used and handled a few, seen others perform in matches. That said, whatever you get, I would tell you to go with upper/lower from same manufacturer. Tolerance stacking, blah, blah...

But of all of them, I recommend and see less (no) issues with tuned EPCs. I also love a buddies CMMG too.

Other recommendations - pick one mag brand and tune the LRBHO to that mag/follower. I have a few brands, recommend Glock or MagPul Glock pattern mags.

You mentioned optics, I use Primary Arms GLX 1x Prism, green, mounted high for heads up and over the light. Etched reticle, wakes up when you pick it up, good (not blue) glass, tough/solid built, good warranty, etc. Optics are personal, this is my choice.

Light - have streamlights and surefires but for these I added a Holosun P.ID light/laser. Designed for handguns (??huge) but I love them for this use and set them at 12 o'clock on the end of the handguard, just overhanging. You can use the light/laser individually or in combo. Great at night matches to 75-80 yards (farthest I tried at night).

Search the googles for "blowback9" and check out his website. If you have a bunch of questions, maybe buy him a coffee (he has a link) and ask questions, he responds! Has great testing data and other links to good info.

Good luck and have fun! Feel free to PM.

Thank you for the reply. This is what I was hoping for. I'd like to buy once and not try to invent the wheel. I am familiar with Aero, and Ballistic Advantage barrels, I don't even know if they make an upper. I never thought about having the bolt remaining open upon the last round. If Aero works, that works for me. Keeping all the computers the same makes a lot of sense as well

 

[RWE]

Yes, for me, anything that feeds itself has to stay open when empty. Operating procedures for me.

Check those links out, lots of brands and options. CMMG, MaconArmory are good too. Obviously, I like EPC9 but it suits my use cases, yours may dictate otherwise.

With barrels, if you go Aero or BA - Make sure it has the "Enhanced Feed Cone", should list it in the description. Original 9mm AR pattern barrels used the old Colt design of feeding and basically it has to hit the hole just right. The "enhanced" is just dished out more and it feeds well. JHP too.

They (Aero) make uppers or you can assemble your own. I went did, the RISE Armament PCC trigger is very gtg, Kaw Valley bolt, and with the "Gentle Recoil System" as described by blowback9. I do want to try some of the delayed blowback systems. Lots of options, remember, the simple PSA set up works too... Heavy bolt/buffer combo is the way to go, 22-26oz total. Ish...

 

[Hydra6]

Daniel Defense now makes a complete 9mm PCC. JP Rifles is well known for AR style PCC for competition but also they market for LE use. If you want something dedicated to 9mm - SIG MPX. I have a SIG MPX SBR.

 

[RWE]

I agree, the DD is nice and runs well. The JP and Sigs are also great options.

 

[Dash734]

smart call building an AR9 PCC before your state's AR ban hits plenty of time to Lego it together for HD range duty. Blowback operation is spot on for 9mm lowers, and yeah, accuracy functioning is easy with quality parts. Your Ruger's 4-5" at 100 yds is solid baseline an AR9'll tighten that to 2-3" with a good barrel upper.

 

[Alibiiv]

smart call building an AR9 PCC before your state's AR ban hits plenty of time to Lego it together for HD range duty. Blowback operation is spot on for 9mm lowers, and yeah, accuracy functioning is easy with quality parts. Your Ruger's 4-5" at 100 yds is solid baseline an AR9'll tighten that to 2-3" with a good barrel upper.

Thank you for the reply. My son picked up a complete lower for me, and I just picked up an Aero upper. The next items are the butt stick and a bolt carrier group. Then we will LEGO the rest of it. It is coming together.