AR carbine 9mm, 300blk, other?

[NIGHTLORD40K]

General purpose for the gun is essentially a range toy. It may be employed as a short range deer hunting gun for the kids, which is why I’m not headed straight to .450bm. One daughter has fallen in love with my marlin 62 30 carbine which is adequate for short range. The other daughter likes my 6.8ar but it’s about 3 times as heavy as she can handle. I want light weight, lower recoil, but bigger bullet than 224 diameter. Things like 6arc would be great but I don’t want to drop a grand on a build that I have little use for. 9mm seems logical since I reload and have a pile of components already. Using beretta mags would be awesome but I expect Glock-mag blocks to be more easily sourced and more reliable. I also like the thought of a short stubby subcompact mag for hunting and a long aftermarket mag for range fun.

My daughters AR9 build uses the Stern magwell adapter for Beretta M92 magazines. With 450 rounds down the tube we have had zero FTF and only 2 FTE. Of the 2 failure to eject, one was on the very first test firing, and the other occurred when a casing got stuck at a 90deg. angle to the port- which of course is sized for a .223 case, so that wasnt the fault of the lower or adapter.

The Stern adapter wasnt cheap, but the quality is top-notch and ours has been awesome. Highly recommended!

 

[herrwalther]

I digress. If you want to do it “correctly “ you’d buy a pistol lower to accommodate your pistol upper. But, like others said, there’s always a way around it..

With prices of everything right now, I am all about versatility. If I were going to build a PCC, I would save more than half buying adapter parts compared to buying everything dedicated. Far cheaper to swap out a buffer, magazine adapter, barrel, and BCG. It is great to have the options we have.

I am not a fan of PCC at all. Doesn't fill any niche for me that I can't do with a handgun as far as defensive use. If I were going to dump serious money into a compact AR project it would be a 7.62x39 build. A true mutant AR/AK hybrid. Use AK mags with the KS-47 lower receiver, controls of an AR, in 7.62x39 like the AK. Ideally it would work on a piston system like the BRN-180 so it could be fired with a folded stock, but I don't know if anyone makes those in 7.62x39.

 

[Lennyjoe]

If I were going to dump serious money into a compact AR project it would be a 7.62x39 build. A true mutant AR/AK hybrid. Use AK mags with the KS-47 lower receiver, controls of an AR, in 7.62x39 like the AK. Ideally it would work on a piston system like the BRN-180 so it could be fired with a folded stock, but I don't know if anyone makes those in 7.62x39.

Now that sounds like a fun build!

 

[herrwalther]

Now that sounds like a fun build!

I got the rough idea about a week ago watching a video about the Galil Ace. IWI makes one in 7.62, closed receiver, with a pistol brace, and uses AK magazines. Controls are similar to an AR but not quite. This is the closest to a dream build as I know of.

https://iwi.us/product/gap39iisb/

 

[tater1961]

I m running the 9mm CMMG RDB system with endomags.
Its built on a mil spec upper and lower. Running a mil spec carbine buffer and spring. The RDB system gives a milder recoil than the regular blowback system. I have had zero problems with mine. There are some reports about ejection issues. I think they have worked the problem out with a different ejection spring.

Another plus with this system is you can pop your 2 takedown pins, and slap another upper on your lower. No buffer or spring change. Put your upper on and put a mag in your ready to go.
I m not affiliated with cmmg whatsoever. This RDB is dependable and a blast to run.

 

[wally]

I’m sure it goes without saying that your current lower (if made for AR15 mags) won’t work for a handgun cartridge like 9mm.

You can get "mag blocks" to convert the standard AR mag well to use 9mm Colt (modified UZI mags) or 9mm/.40S&W Glock mags. The blocks are on the expensive side, but you don't have to bother with FFL transfer fees and can just buy the upper on-line.

I use them in my registered SBRs, very versatile. What I don't like about .300 BLK is that with a bit of bad luck (if the bullet "sets back" instead of jamming) you can chamber the round in a 5.56 upper and have a nice KaBoom!

 

[greyling22]

I’m sure it goes without saying that your current lower (if made for AR15 mags) won’t work for a handgun cartridge like 9mm. If you plan on using your current lower for your build then .300 BO would be a good choice since you have .30 caliber bullets on hand.

yes it will. use a magblock or even better, the mean arms endomag.

that said, I have ar uppers in 9mm, 300, 6.5 grendel, and 223. I hunt with the grendel, shoot the 9 for fun, and the other 2 just sit in the safe. I highly recommend a 9mm ar using the cmmg banshee radial delayed blowback system and an endomag. The banshee ar was WAY more pleasant to shoot than the direct blowback 9mm ar I had before.

 

[jeff-10]

If I did didn't go .223 on an AR it would be 350 Legend unless I was buying a suppressor also. Then 300 BLK.

Anything but 9mm or 7.62x39 is going to be much more pricey than .223. If I wanted 7.62x39 it would be an AK.

 

[Walkalong]

.223


300 BLK


9MM

 

[rdnktrkr]

I like my 6.5 Grendel, accurate and easy shooting with enough pop to comfortably hunt deer with, I've been looking at the 350 legend and 300 BO as a new build but I got side tracked this year.
A friend has a Hi Point 9mm carbine and has enjoyed it, he reclaims his lead and cast new bullets. When he bought his they were cheap

 

[Elkins45]

I hate 9mm AR. I love 300 Blackout. 9mm AR splits cases and fills your face with metal. I couldn’t sell mine fast enough.

 

[Walkalong]

9mm AR splits cases and fills your face with metal. I couldn’t sell mine fast enough.

Something was wrong with yours.

 

[Walkalong]

.22 LR (I believe in diversity in ARs)

 

[Elkins45]

Something was wrong with yours.

Yeah, it was a blowback gun and I'm left handed. The AR wasn't designed to be a blowback gun. My particular specimen was a PSA dedicated Glock mag lower, so it ostensibly came with the "correct" spring and buffer for 9mm. Didn't keep it from swelling cases and spitting gas in my face.

The one that filled my face was a pistol braced conversion using a Sylvan mag conversion, Midway bolt and a Brownell's extra heavy buffer. That was with factory Blaser ammo. The bullet setback was from me driving the front of the case and the bullet out of the chamber from the muzzle end.

9mm AR is bad juju to me. Me no want.

 

[Elkins45]

I finally settled on a 308 recoil spring and a homemade buffer made from steel conduit and poured full of lead. I had almost a full pound of mass reciprocating with every shot, but at least the gas had left the barrel before the case was out of the chamber.

To say that it chambered rounds with authority would be an understatement!

I still have all this stuff from the conversion kit but I'm never going to shoot it again.

 

[BreechFace]

Something was wrong with yours.

I agree. There are lots of AR PCC’s utilizing direct blowback out there.

I’m not suggesting you didn’t have problems with yours but with as prevalent as they are today it makes one wonder what’s going on with yours in particular.

 

[H&R Glock]

AR9 just fine- two ARAK's just fine, AR556- just fine- you need to see a gun smith if you have that much trouble. Bloated brass and blown cases are a disaster caused by basic problems. They can be fixed! Don't give up!

 

[Chuck R.]

IMHO, like most things, it really depends on your task/purpose (and budget).

I've got both a 9mm PCC and a .300AAC, both are for distinctly different purposes and the guns are configured differently.

My 9mm PCC is a Colt AR6951 that's set up like my HD AR15, it's used for practice, plinking and PCC matches. 9mm is cheap and easy to load for and I run the same loads I do in my match pistols. It is a great gun for new shooters to work on learning the AR15 and some CQB shooting. The 9mm doesn't screw up my AR500 plates when shooting close. IMHO for these purposes, the 9mm blows the .300AAC away:



My .300AAC is set up in a pistol configuration with a 9.5" barrel. IMHO the .300AAC shines in shorter barrels as it has a ballistic advantage over .223/5.56 in the shorter tubes. My AR15 pistol is used for HD and as a "truck gun" when travelling. I load for .300AAC, but not quite as cheaply as I do for 9mm, it's also not as easy being a BN cartridge. IMHO for these purposes, the .300AAC in this configuration blows the 9mm PCC away.



I also own 3 other AR15s in .223/5.56 and a .22LR, they also have their own task/purpose.

 

[bullseye308]

I cheated and bought one from PSA. Got the 8” AR-9 that takes Glock mags and have run several thousand rounds through it with 2 malfunctions, one of which was definitely ammo related and my fault. Before the stupidity hit it was 585 delivered and I really should have gotten another.

The vortex came with an AR kit also from PSA and the discreet carry case from evilbay. This is my car gun as legally it is a pistol and it maneuvers much better in a vehicle than a standard AR. I replaced the muzzle device with a cheap linear comp from evilbay for 18.88 and it does make a difference.

 

[Crosshair]

With 115 grain bullets and the fact that you reoad, have you considered the 300 Ham'r?

Sacrifice subsonic performance for improved supersonic performance. Plus you can make it from 5.56 range brass with a simple necking up.

 

[horsey300]

General purpose for the gun is essentially a range toy. It may be employed as a short range deer hunting gun for the kids, which is why I’m not headed straight to .450bm. One daughter has fallen in love with my marlin 62 30 carbine which is adequate for short range. The other daughter likes my 6.8ar but it’s about 3 times as heavy as she can handle. I want light weight, lower recoil, but bigger bullet than 224 diameter. Things like 6arc would be great but I don’t want to drop a grand on a build that I have little use for. 9mm seems logical since I reload and have a pile of components already. Using beretta mags would be awesome but I expect Glock-mag blocks to be more easily sourced and more reliable. I also like the thought of a short stubby subcompact mag for hunting and a long aftermarket mag for range fun.

Soooooo just an update, I found subsonic ammo for the .450 at my lgs!!! (New to me) if you weren't aware of this, does it make a difference for you?(kinda did for me)

 

[sevt_chevelle]

I feel 7.62x39 is a waste of the AR’s accuracy potential.

I built an AR in 7.62x39, bought a barrel from Satern, it shoots nothing but cheap ruskie ammo and rovers around the 1.0 to 1.5 range all day long.
Lent it to a coworker who needed a deer rifle this season, never shot the rifle before, he put 5 rounds of Wolf into a group at 100yds with all 5 shoots touching.

 

[M1key]

I traded into a like new Colt 20 inch upper last year. I've set it up on an RRA carbine lower with iron sights. I haven't shot it with a scope yet but what little I've shot it with 123gr Gold Dot reloads it is amazing. I plan to scope it and shoot off the bags but our county range has been deemed "non-essential" by our governor, so it will have to wait.

M

 

[Bcwitt]

762x39 is a loser in the AR. The magazines are very cheaply constructed & the straight well of the AR dosent work well w the very tapered 762 round. Also has issues w bolt cracking.

 

[BigBore44]

762x39 is a loser in the AR. The magazines are very cheaply constructed & the straight well of the AR dosent work well w the very tapered 762 round. Also has issues w bolt cracking.

Interesting. I have 2 x39’s. 16” HBAR’s. I run C-Products Duramags exclusively in them and my 450’s. Never had any type of problem. Not with my handloads. Not with Wolf or Tula. The AR platform USED to have have problems feeding x39. They fixed that problem quite awhile back. Not saying you have to magically accept what I’m saying as gospel. Makes me no difference really. But the issues were resolved. The bolts breaking seemed to be from using a 5.56 bolt that was thinned. And using a cheaper alloy. There are fixes for that also if you had that problem. I have had no such issue. My accuracy has been better than expected. And I have a few thousand rounds down the tubes. Off the top of my head I personally know 6 people with x39 AR’s. Every issue that has been had with those rifles was a magazine problem (fixed by purchasing DuraMag) a separate feeding issue (caused by using the mag as a POC while prone (newbies) and a firing problem caused by some cheap no name ammo that wouldn’t fire in any of the rifles we had with us.

To blatantly state that the X39 is a loser in the AR, is simply false. It’s anecdotal evidence at best. Likely old anecdotal evidence.