9mm AR pistol questions

[krw]

Wanting to build like a CMMG Banshee clone. To start off with I dont know squat about AR9 pistols!
1 I know they operate by blowback and not gas operated like most AR’s. Do I need to get BCG and barrel from same company or do all interchange?
2 What weight Buffer and Spring do you use with 5-7” barrels?
3 Will shoot it suppressed 99% time. Will it be as quiet as a suppressed Scorpion? Thanks

 

[SporterII]

Port noise with blowback 9 Ar is not bad but present. These will never sound like a 22lr bolt gun. Barrel length won’t determine buffer choice. I have only ever used Colt rifle buffer/tube /Stock(A-1), my fave. Skorpion is entirely different and was never of interest so hope someone else chimes in for you.

 

[tomcatfan]

If you use the banshee system then no the bolt and barrel are not interchangeable with other systems as it uses a delayed blowback system. Its kind of like DI vs. piston in some ways. Most other systems are interchangeable. A faxon barrel will work with a spikes, foxtrot Mike, fail zero, etc. you just have to make sure you stay on the same system.
Most buffer and spring combos will be marketed as for a 9mm pistol. Mine were. Some bolts come with interchangeable weight systems too, but barrel length doesn’t drive that bus either way. A 5” barrel would use the same as a 10”.
Cant speak for shooting suppressed.

 

[roostercogburn98]

4.5 inch barrel using 3.8g of titegroup behind a 124g ball is pretty dang quiet. 100% function in my sbr setup. Build is an old school (built in 2012-13) CMMG upper and lower based on uzi mags.

 

[mewillis]

I bought a PSA Gen. 4 AR9 complete, runs like a sewing machine, uses Glock mags flawless feeding, had 1 jam when new but going on 400 now without a failure. I use an old Gemtech Tundra which is crazy quiet with super supressed Win. 147gr. and IMI 158gr.
I paid half of what a Banshee costs........

 

[Strykervet]

Is it a range toy? I didn't want a range toy so I went with JP but thought I could make a reliable one on a budget --and maybe you can but I wasn't comfortable with what I learned/found. I'm sure there are others besides JP but that's the only one I really felt comfortable with after digging around --I swear by their AR BCG's already. 9mm AR isn't standardized at all and it seems like there's a LOT more junk parts in that size too. Or parts that just don't work well. Then mixing and matching shit... Some of the barrels are chamfered at the chamber, some aren't. Some bolts work with that, some don't. Then there's the recoil system, holy shit... The list literally goes on and on.

At the end of the day I placed an order for the JP barrel, standard stroke bolt and captured spring system. SCS2-9-5H2 and their 10" bbl. (seems like I could find nothing but junk barrels too). Whatever you do, you want those three parts to work well together. The JP junk can be tuned and they've put a lot of work into making their system function well, it's possible they've put the most work into it period, catering to 3gunners and such.

I've got a Tavor 9mm that uses the same mags, why I wanted this thing in the first place, same mags. Anyway, Tavor is a damn hard to beat 9mm and it functions with all ammo, suppressed or not. Even mixed mags in the rain with shit in the action. So I'd get good parts and be prepared to wait for 'em, maybe get a Tavor on GB in the meantime and beat up on it until your parts arrive. Then keep it or sell it but mine is a keeper. Just don't buy a Kriss.

FWIW, JP has a short stroke bolt/buffer assy. (it's not guaranteed to lock back under all conditions like the std. one though) and later this year they're supposed to be releasing a roller lock IIRC.

The reason some of these other companies are using rotating bolts is, IMO, probably because it's cheaper --9mm and 5.56 basically use the same bolt face and extractor. So modifying it so it'll "slip" under recoil (that's where the delay comes from, it really doesn't lock at all in the true sense of the word) seems to me like a solution to a problem that didn't exist as well as introducing failure into the system. Looks like a 5.56 system with the locking lugs cut at 30-45deg. to match similar cuts on the extension.

 

[krw]

Thanks for all the posts! I picked up a Rock River strippd lower for 9mm Colt style mags. Went this route cause I hav buttld of mags
I plan on ordering CMMG radial delayed blowback BCG/bbl combo. Will chk on that tomorrow and see expected ship date. Hopefully rest of parts can fall into play fairly easily

 

[kl3309]

Thanks for all the posts! I picked up a Rock River strippd lower for 9mm Colt style mags. Went this route cause I hav buttld of mags
I plan on ordering CMMG radial delayed blowback BCG/bbl combo. Will chk on that tomorrow and see expected ship date. Hopefully rest of parts can fall into play fairly easily

You do know that the new CMMG radial delayed setup for colt-style mags uses a different ejctor, feed ramp, and bolt hold-open, than the previous CMMG straight blowback rifles, right? Not sure if the retrofit kit that they sell is applicable to a RRA lower.

 

[AHorn]

Just buy a banshee, tight ass. This has dun got WAY over your head .

 

[krw]

Think ur prob right!!