Gun and Game Forum banner

AR Pistol Build...maybe

6K views 36 replies 9 participants last post by  Kaybe 
#1 ·
I was considering building an AR pistol. I was thinking about adding the folding buffer tube adapter, just thinking about it. I have seen AR pistol barrels with a straight gas tube and a "pig tail" gas tube. Are the pistols reliable with standard ammo? Need special ammo? Do I need the pig tail gas tube or will straight due? Anyone with experience, please let me know. Thank you!
 
#7 · (Edited)
Don't have too much experience with pistol builds. All my SBRs are 11" and 10.5" setups that run carbine gas tubes and receiver extensions.

I have one 8.5" .300 blackout barrel with a corresponding pistol length gas system and a carbine receiver extension. Technically the equivalent of a carbine receiver extension and buffer as it's a non standard setup with a PDW stock (see my 300 blackout SBR thread).

For the Pigtail vs straight... for full sized carbine setups people typically just recommend to use a straight mid length system system and call it a day.

The concept/idea of the pigtail system is to give you added gas tube length per square inch because you now have more tube wrapped around the barrel in the same space as a straight tube...

But regarding dwell times and things like that... you can do more with just putting in a heavier buffer on the other end. Many consider it to be sort of... not worth it.
 
#8 · (Edited)
I have built two--300 BLK 8.5 and 5.56 10.5"

Mine are fine with a standard pistol length gas system on the former and carbine gas system on the latter.

I use a pistol buffer tube and shockwave brace.

They have run fine on most ammo, but there have been some glitches. The 300 does not always like cartridges with the sierra 110 JHP (it does fine with full length 150s, 147s, and 125s) -- it's somewhat sensitive to shorter OAL cartridges. Polishing the feed ramps helps but I sometimes get a 3-point after the action gets grungy with the short cartridges. Longer ones no problem.

Mine were designed to run suppressed. I also like to be able to run them unsuppressed so they have a normal weight chrome silicon spring but a Spikes Tactical T2 buffer. This results in the 5.56 being slightly under gassed (with low power ammo) sort of (it's still properly gassed it's just that the buffer is heavier) and slightly over gassed with suppressor (same thing; technically not overgassed but the BCG/buffer combo is just a bit light). The 5.56 has had no problem with 5.56 ammo, but has had some issues when the BCG gets gunked up from shooting suppressed then going to unsuppressed shooting PMC ammo (which is lower powered 223 ammo--2900 fps). It does fine unsuppressed with 5.56 or the standard (hotter) 223 ammo like finocchi or the gold dot 64s (which are my standard defensive round these days--psa sells them for 9.95 per 20). And no problems running suppressed.

Like thrillbilly said I consider 10.5 the absolute min due to too much vel loss below this for 223/556. If you're going to go shorter you can go 8.5 with 300 blk (the 300 was designed to be run in shorter barrels and burns efficiently in them).

I WOULD go with a nickel boron BCG if you're running suppressed due to the soot buildup from the suppressor. I wound up switching from EWL--which I really like--to my own lube brew in a dunk tank as a result of this for the suppressed guns. Standard ARs have no problem but the suppressor adds a fair bit of blow back. What I usually do is wipe out the receiver area and BCG first and then dunk the BCG for a bit (cycling the bolt in the tank) and this seems to clean stuff out without necessitating a huge drama and teardown after shooting a few hundred rounds.

Here are pics of mine (They have 1-point slings now; I don't really like the brake but it came standard with the Omega and the gun is suppressed most of the time; I prefer the 3-prong specwar flash hider/mount):
Gun Airsoft gun Airsoft Games
Cameras & optics Camera accessory Tripod Airsoft gun Games
 
#9 ·
Thanks for all the replies. I wasn't going to go surpressed. Not really into going down the class III rabbit hole yet. Recent article on a 6 inch 5.56 with folding buffer tube and TAC2 system had me thinking about a pistol. I wasn't going to put a brace on it, but that is just me. It would be a range toy. I have fired a mag out of a pistol a couple of years ago and it seemed to ok. I just want it to be reliable and most of all, fun. I wasn't going to put all the tacticool stuff on it, just a small red dot and sling.
 
#10 ·
Mine all have a sling, a light, and some type of optic. Think that's enough for me.

I wasn't a suppressed kind of guy until I gave some thought to what setting my rifles off indoors would do to what's left of my hearing. They're loud enough as rifles, and making a pistol build is even louder. So I took the plunge and got the stamp (have an omega, still waiting on the K-556). It's not too onerous, but it is more expensive (for no good reason) and there's a huge wait time at present. Suppressed fire is quite a bit more quiet and friendly, and while still loud with supersonics, isn't dangerously loud. So I've grown to like it very much.

In fact, what got me into pistol builds is a rifle with a suppressor is kinda unwieldy to handle indoors but a pistol build works fine. Kinda pretty close to an AR length to begin with.
 
#13 ·
Still working on my 80% pistol build. I got it together enough to know it works, just need to finish it now. It is a .223/5.56 7.5" 1 in 7 twist free float handguard ear drum buster. YES it is very loud. It is only accurate out to about 100yds.

I hunt deer with a .300 blk pistol it is dead accurate out to 125 yd with supers. Great gun!
 
#16 ·
Im becoming more interested in a pistol AR myself. Id probably be going with a 12" barrel and non suppressed. with some type of "arm brace" to help with accuracy.

the goal being a handy little rifle that could fit in a back pack, my current 16" upper is about 4" too long to fit in my BOB.

I dont want to go too short though because of the rather drastic velocity/ accuracy loss. .300 blk has crossed my mind but i just dont want to have to adopt another cartridge.

I most people and guns I have seen use straight, either pistol or carbine length gas tubes. It's my understanding the pigtail ones would be for super short barrels.

Im thining of running something like the Noveske PIG FLash Suppressor to make it alittle more bearable without being full suppressed. My thought is that it might direct more of the blast/ concussion forwards rather than to the side like most brakes.
 
#17 ·
Im becoming more interested in a pistol AR myself. Id probably be going with a 12" barrel and non suppressed. with some type of "arm brace" to help with accuracy.

the goal being a handy little rifle that could fit in a back pack, my current 16" upper is about 4" too long to fit in my BOB.

I dont want to go too short though because of the rather drastic velocity/ accuracy loss. .300 blk has crossed my mind but i just dont want to have to adopt another cartridge.

I most people and guns I have seen use straight, either pistol or carbine length gas tubes. It's my understanding the pigtail ones would be for super short barrels.

Im thining of running something like the Noveske PIG FLash Suppressor to make it alittle more bearable without being full suppressed. My thought is that it might direct more of the blast/ concussion forwards rather than to the side like most brakes.
Griffin also made a blast shield doing this which attaches to the standard A2 flash hider with a minimum amount of trouble. Just clip it on. It directs the blast forward.

10.5 or better on a 223 seems reasonable with the right ammo, although I wouldn't use FMJs for anything but target due to the velocity loss. There are a plethora of internet tests done and shots at reasonable ranges are OK. If you want something more (or defense against thicker skinned threats) you'll probably have to step up to the 300.

Accuracy has never been an issue; if you're looking for sub-MOA maybe not as much but any pistol build has been more accurate than my full length minis (which I do like but also recognize their limitations). And on par with other intermediate level AR rifles.

If you can get over the wait time and the stamp though, I'd HIGHLY recommend going the suppressed route if you can. It's not much trouble at all once you get it (just a suppressor tube to carry around; you can carry the stamp paperwork if you want but I just scanned it in to the cloud and can access it anytime if anyone ever wants to see it which nobody ever does). It makes quite a difference to me. And it isn't too hard to get the gun to work both suppressed and not, although you do have to dunk the BCG more often IMHO and wipe out the crud in that it does throw more stuff in the upper receiver. But every few hundred rounds is more than enough.
 
#19 · (Edited)
You might want to consider this:

I did the SBR registration because I wanted a pistol grip on the for-end for better control (already had one lying around gathering dust) and a folding stock as well. Also whichever you decide on, Hornady recently came out with an SBR designed ammo in 5.56 which I find to be quite accurate. The AK is just as reliable and much less expensive.
 
#32 ·
Another benefit for the Vortex Flash Hider is the ability to directly fit their Windtalker QD Suppressor. I have one for my Rem 700 and it also fits the Zastava albeit not as quiet as the 700 due to the fact it is a .308 can and that the short barrel does not give enough time for the powder to burn off; although the Hornady ammo helps.
 
  • Like
Reactions: TXplt
#33 ·
I think the key is if you have a choice, consider a FH which might support a suppressor you might want down the line. As it is (notwithstanding any potential of legal changes of old and outdated NFA laws) the suppressor is the limiting factor; the guns and parts are easy to get while the suppressor takes way too much time (like almost a year and costs an extra 200 bucks to boot). Having common FH fittings has worked well in moving the suppressor to different guns and is a major factor in which ones I choose moving forward.
 
  • Like
Reactions: Kaybe
#36 ·
I know they call it a flash "suppressor" but really all it does is direct all the blast forwards... and with a short barrel chambered in .223/5.56 there will be a blast lol. That's why they have the pic of the flame spitting pig on it.

You won't get nearly that blast with .300 blackout (yes I know you don't want to go to another caliber)

Those things are also heavy. They add 7 oz. to the end of your barrel.

The weight and length is why I don't have a pig.

I'd rather have a 12.5-13 inch upper with a2 fh, versus my 10.5 with a pig.
 
#37 ·
Getting a flash hider that will support a suppressor might be the way to go...just in case the "whisper" bug talks to me.
Anyone have any issues with the .223 Wylde chambered barrel? I want a heavy barrel for the pistol, not contoured. The Wylde seems to be the choice in 7.5 inch.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top