Let's talk AR pistols... barrel length and caliber suggestions welcomed.

[Lebowski]

I don't know what the appeal is but I've been wanting to build an AR pistol and am starting one.

Since I've not started assembling anything yet and don't have any upper related parts or the BCG, choosing a caliber and barrel length is still open game. It's a standard 223/556 lower so that's the only limiting factor at this time, but most pistol calibers should work with that anyhow.

I originally was just going to go short (7-8" barrel) with 556... but that may not be a very effecient setup. I'll take the barrel out to 10" and am open to any caliber options that would work well on a 10" barrel.

The AR pistol is going to be mainly for fun and plinking at ranges from 25-100 yards.

Thoughts?

223/556, 300BLK, 6.5 or regular pistol calibers like 9mm?

9mm may be fun to shoot from an AR platform.

Unsure if I can ever legally make this a SBR or suppressed since this build is based on an 80% lower. Haven't read stamp requirements for such things so this will probably stay a pistol and a regular ol' AR pistol only.

 

[Bfish]

You can do a 556, nothing wrong with them. Great length seems to be 10-11 IMO.
However, I would strongly consider a 300blk! It begs to have a 9-10 barrel! Mine is in pistol form right now awaiting a form 1... Either way you would like it I'm sure!

 

[Lebowski]

223/556 certainly has the advantages of being available readily and is affordable-ish. Plus I don't like having a ton of different calibers to stock.

Though I thought the round didn't perform so well from short barrels? I'm not looking for competition grade accuracy at phenomenal distances but I also don't want to be frustrated with a poor performing setup.

 

[Bfish]

Yeah. 223 is certainly more available and a bit cheaper. 300blk is dropping in price slowly, and it's really cool if you can suppress it or if you reload. However, it sounds like you want to keep you calibers to a minimum... It is also nice because all of the powder in a 300blk burns in roughly 9" or that is the common thing you hear thrown around (from personal observations beyond a chrono,muzzle flash is also noticeably less). To cut to it though, it basically it does very well in a short barrel unlike many other calibers.

Sounds like you are leaning 223 though and that's fine... There is a performance loss with the 223, but nothing you need to worry about at 100 yards and even at greater distances. Most problems with the shorter barrels are A.) cycling reliably and B.) stabilizing the bullet. At 10" you shouldn't have any of these problems. While many people will get them to work just fine in shorter configurations, most people have great success staying at the 10" and above mark, and your performance loss isn't as great.

There is lots of debate and conversation/information to be found on barrel lengths, but what you are wanting will be just fine!

 

[freekforge]

I have onewith a 10.5 inch barrel in 5.56 and besides a few hiccups on the first few rounds it has ran awesome and now resides in a tennis bag goes where ever i go. With 5.56 you have to do some fiddling with them if you go under 10" my cousin built one with a kitty kat upper and we had some issues and had to switch the buffer and spring to get it reliable enough for range fun.

 

[GChambers]

If you already have a .223/5.56 go 300blk with a 9-10.5in barrel and a suppressor. Buy decent brass for your .223, cut the casings and reload them subsonic for your 300BLK. That's my plan.

 

[SSGSAD]

300 blk .....

 

[EvilKidsMeal]

Yea, I'm in the process of a 300BLK pistol. I have the lower with parts installed and the pistol buffer kit is on its way. I am planning on getting an 8.5" upper. I want this bugger to be as small as possible without hampering performance. I have heard that 9" is the butter zone for 300BLK so I figure a 1/2" barrel loss won't hurt performance. I too have a tennis racket bag I plan on carrying it in, in my car while I'm out.

I already have about 220 converted 5.56 cases that I did myself, and am in the process of cleaning and sorting about 1,400 more cases. About half or so I will convert as well.

 

[Psode27]

Balistics.... pshhhh..... haha I have a 223 with a 7.5" upper and its been 100% reliable, no issues at all! That being said, i'd probably go with 10.5" if I had to do it over again (I got a 7.5" on trade). there aren't a whole lot of reasons to go 7.5 aside from cool-factor.
If 300blk is your thing, then that might be the way to go. I have no first hand experience there, though I will soon in the form of about an 8" SBR likely.... Probably can't go wrong!

 

[Tactically Fat]

Go 9mm...

Then later, as funds allow, build a .223 upper as well!



My 9mm upper for my pistol is in route as I type this.

I've tried to convince my wife that I need something in 5.56/223 as well - but no dice so far. :-/

 

[rvb]

9mm is really fun, and you can go really short since no gas system. mine is a 5" barrel (SBR, not pistol). w/ silencer it is probably as long as a 10.5" gun w/ muzzle device.

-rvb

 

[Zoub]

I never wanted one until .300blk came along. I did it as a stepping stone to an SBR that I use to hunt with and will now add a can. I did 10" as I see no reason to run on the ragged edge of fail, especially with a can coming next. A 10" + can equals AR's I already used for hunting. I am comfy with that.

Otherwise 9mm would be more useful and easy to get good advice on. This is where buying local can be a wise choice. You buy from a local shop that has knowledge of the project you are doing.

For me, in Indy, that would have been Mark at Bradis. Back when he and Bigcraig were just getting out of their diapers, I watched them make theirs go. Knowledge like that is priceless and saves the customer lots of money, time and heartache.

As a matter of fact, even though I am 500 miles away, I would still have Mark set me up if I did a 9mm.

 

[rvb]

nothing hard about a 9mm.
1) go "colt pattern"
2) metalform mags only
3) use the correct style hammer/bolt/buffer.

it'll run.

-rvb