Let’s talk about AR carbines.

[Eoddave27]

One of my local ranges that does steel matches has a carbine division. I am thinking I want to build myself a AR in 9mm. I am eventually going to get a CZ scorpion but I really want to build an AR first. My son will be shooting with me so once I get the CZ that will give each of us a rifle to shoot. I want to stick with a rifle length and not and SBR. I’m not real big on pistol size AR’s with a brace either. I’ll probably stick with 9mm just because ammo is so cheap. The thing is I have zero experience with AR’s in pistol calibers. I want to avoid building a rifle then realizing I should have done something different and needing to build another to get it right. My question is what are some of the things I need to know. Is a lower designed as a carbine or a standard lower with an adapter better? Are there any bolts that I should steer clear of? Am I better off just buying a complete upper? Is there a good break that is fairly quiet that helps to control muzzle rise? I could go on but I’m guessing you guys who have built these are a lot more familiar with any issues you can have with these than I am at this point.

 

[TonyTheTiger]

Is this like a Steel Challenge match? If so light weight is the name of the game, if more like USPSA it's not as important.

Mag blocks are ghey, get a dedicated lower.

Colt mags suck to load, Glock mags don't.

Brakes do little to nothing on 12"+ barrels, there's very little gas pressure given the small amount of powder burned and the large volume of bore.

The CZ Scorpions have possibly the worst trigger of any firearm ever, budget for an upgrade immediately.

Buying most important parts from the same company seems to avoid a lot of issues, e.g. all JP or all Taccom for bolt/buffer/spring systems.

 

[oldfatguy]

Colt mags suck to load, Glock mags don't.

Lula loader makes loading Colt mags very, very easy. That said, most 9mm PCCs are going to Glock mags. The CMMG RDB system is only available for Glock mags.

OFG

 

[Darqusoull13]

One of my local ranges that does steel matches has a carbine division. I am thinking I want to build myself a AR in 9mm. I am eventually going to get a CZ scorpion but I really want to build an AR first. My son will be shooting with me so once I get the CZ that will give each of us a rifle to shoot. I want to stick with a rifle length and not and SBR. I’m not real big on pistol size AR’s with a brace either. I’ll probably stick with 9mm just because ammo is so cheap. The thing is I have zero experience with AR’s in pistol calibers. I want to avoid building a rifle then realizing I should have done something different and needing to build another to get it right. My question is what are some of the things I need to know. Is a lower designed as a carbine or a standard lower with an adapter better? Are there any bolts that I should steer clear of? Am I better off just buying a complete upper? Is there a good break that is fairly quiet that helps to control muzzle rise? I could go on but I’m guessing you guys who have built these are a lot more familiar with any issues you can have with these than I am at this point.

If you want a no nonsense rifle that both you and your son can both run invest in a JP GMR15. I have between 25,000 to 100,000 on various individual JPs and they just run. Loaned out at matches with random ammo or heavy practice sessions.

GLOCK mags, barrel that feeds anything 9mm you can shove in a mag and phenomenal fit and finish.

 

[padom]

7.5" AR15 9mm with dedicated can is my sons favorite gun. He essentially steals it from me every time we go to the range. Runs like a swiss watch, virtually no recoil, super accurate. I run glock 32rd mags and have a few with the Taccom 65rd billet extension which runs great!!


Spartan AR15 Billet 9mm Glock lower
Spartan AR15 Billet 9mm Upper w/LRBHO
7.5" Wilson 9mm 416SS Barrel Threaded 1/2-36
Seekins 9" MCSR Handguard 1.80" ID to fit can under handguard
Spikes 6 Position Adjustable Buffer Tube
Magpul CTR
Geissele SD3G Trigger
Toolcraft Nitride 9mm BCG
KVP 17-4 Extra Power Buffer Spring
KVP 10oz SS Blowback Buffer






115 FMJ




165gr subs

 

[Eoddave27]

Padom, so if you are running that with a can will that get you around the SBR rules? If so that is defiantly an option.

Tony, this is a falling steel style match. It is all about speed for this rifle. Also I have shot the CZ and you are right. The trigger stunk.

So it sounds like the best bet is to pick a good maker and get all the major parts for the upper from them. I’m a big fan of JP and Wilson Combat. I guess I will take a look at those. I’m not familiar with Spartan but I will take a look at them too.

 

[TonyTheTiger]

I’m not familiar with Spartan but I will take a look at them too.

Its the in house brand name that JoeBobOutfitters uses. They're made by New Frontier Armory and are a known good product. I used their lower for my PCC and its great.

I built it light out front for transition speed, 4" barrel with a 12" aluminum tube pinned/welded on. Taccom 3 stage buffer. The recoil is weird and harsh compared to a well tuned 223 AR but the dot tracks really flat, which you can kinda see in the last practice video I took a few months ago.

 

[WestDesertPRS]

Something to think about is that most AR15 PCC don't lock the bolt on last-round. If you want that feature then you'll need to make sure your chosen brand includes it. The Spartan / New Frontier brand mentioned earlier has the LRBHO built into the upper.

I'd also just go dedicated lower for Glock mags and not mess around with mag-adapter blocks or anything like that. Glock mags are cheap and plentiful and if you go 9mm then you can get the 33rd mags for the G18.