Shorty AR-15s: 9mm vs. .223 ?

[MatthewVanitas]

I've always lusted after little shorty AR-15s like the DPMS Kitty-Kat and the XM607 Vietnam-era mini-M16. They seem handy, "cute", and out of the ordinary yet still using mainstream parts and accessories.



However, the more I've heard about shorty ARs, the more problematic they seem. My (chairborne-commando) impression of .223 7"-11" ARs:
--Loud, huge muzzle blast
--Gas-cycling issues
--Can use a Noveske to redirect the noise, but tricky to use with cans b/c of likelihood of baffle-strikes
--Notable loss of velocity, though not as bad as some folks imply


Given those issues, would a 9mm shorty be just about as cool for plinking and gaming? Maybe 7"-10" barrel, no gas issues with the blowback mechanism, collapsing stock, put a nice big can on it too balance it out and get max suppression, etc. I've seen some sub-sonic .44Mag bolt-rifles that sounded "movie quiet", so I'd hope that a 9mm subsonic rifle with a good can would also be extremely quiet.

Does a .223 11" AR still greatly exceed the 9mm AR in terms of useful range, and general ballistic utility?

Does anyone here have a 9mm Shorty-AR? Comments, reviews?

-MV

 

[shark3-1]

I've always lusted after little shorty AR-15s like the DPMS Kitty-Kat and the XM607 Vietnam-era mini-M16. They seem handy, "cute", and out of the ordinary yet still using mainstream parts and accessories.--Be honest with yourself, if this is going to be a gun that looks cool, by all means, get the 9mm just for ammo savings, and the fact that it's not the norm. If you plan on using it for anything more serious, why would you want a really long pistol?



However, the more I've heard about shorty ARs, the more problematic they seem. My (chairborne-commando) impression of .223 7"-11" ARs:
--Loud, huge muzzle blast---Yes
--Gas-cycling issues---No
--Can use a Noveske to redirect the noise, but tricky to use with cans b/c of likelihood of baffle-strikes---Heat and pressure are the issue, not baffle strikes, get a good silencer. I see the KX3 as more of a solution for rifles with inadequate gas systems. If your rifle works without it, why add that long, heavy thing to the end of your rifle?
--Notable loss of velocity, though not as bad as some folks imply---The 5.56 will generally out perform the 9mm out of all barrel lengths in accuracy, usefull range, as well as terminal ballistics, with barrels shorter than 9" being a possible exception. 9mm will have more penetration.

Given those issues, would a 9mm shorty be just about as cool for plinking and gaming? ---Yes, if ranges are less than 50yds, and ammo is cheaper right now. The 9mm will have more recoil.

Maybe 7"-10" barrel, no gas issues with the blowback mechanism, collapsing stock, put a nice big can on it too balance it out and get max suppression, etc. ---If you want max suppression, go with an MP5 variant. The bolt starts unlocking as soon as the hammer falls on the 9mm AR. Also, more weight in the FRONT of an AR is not going to balance anything out, go lightweight for the suppressor.

I've seen some sub-sonic .44Mag bolt-rifles that sounded "movie quiet", so I'd hope that a 9mm subsonic rifle with a good can would also be extremely quiet.--Sound is relative to the shooter, what makes your ears ring may or may not make mine ring.

Does a .223 11" AR still greatly exceed the 9mm AR in terms of useful range, and general ballistic utility?---You bet your sweet @$$ it does. 9mm will have slightly better penetration depending upon ammo selection and range.
Does anyone here have a 9mm Shorty-AR? Comments, reviews?

-MV

 

[Correia]

10.5 .223 ARs still cycle fine provided your gun is built out of quality parts.

I've not see 7s work as well, but admitedly have not used one very much.

My home defense gun is a 10.5 with a suppresor. Chronos at 2,700+ FPS.

Baffle strikes are not an issue.

 

[Nhsport]

My club shoots a pistol caliber carbine plate match and a couple of the guys have SBR'd a 9mm and they have a cool factor going for them. They are set up with foward vertical grips .Of course in my silly state (CT) we have to have a pre ban lower to put a adjustable stock on it.A little shorty would look silly with a full length fixed stock.
Another benifit of a 9 over a 5.56 is the 9 will be allowed at most indoor ranges and the 5.56 will not.
If one goes the SBR route it is the lower that gets the engraveing correct? Therefore once one did the paperwork and paid the man (BATFE)you could have more than one short upper? Not at all sure how this works,something to check into.

 

[Bartholomew Roberts]

--Loud, huge muzzle blast---
--Gas-cycling issues---

Yes to both in my experience, although guys who know what they are doing can get barrels as short as 10.3" to run reliably (though still less than say an M4 or M16).

--Can use a Noveske to redirect the noise, but tricky to use with cans b/c of likelihood of baffle-strikes---

The KX3 is primarily handy if you are working in an enclosed area with other people. It prevents them from getting a faceful of gas and muzzle blast. I don't know that it is all that useful for range shooting or solo self-defense. A sound suppressor is definitely superior in all the things the KX3 does; but it is more expensive and has more paperwork.

Most of the quality suppressors are warranted on barrels as short as 10.5" though they may require a certified gunsmith to install the mount before they will warranty a barrel that short.

--Notable loss of velocity, though not as bad as some folks imply---

Definitely some loss of velocity.

Does a .223 11" AR still greatly exceed the 9mm AR in terms of useful range, and general ballistic utility?---

I would go with the 11.5" AR myself unless sound suppression and blast were the major issues. You can still suppress an 11.5" 5.56mm down to a level comparable to an unsuppressed .22LR.

I've shot the 9mm Colt subguns and they are a lot of fun, one of my favorites and very controllable; but I think a 5.56mm is more versatile overall. I would only start to look at a 9mm AR if I was wanting a barrel less than 10" and/or blast and noise was going to be a major consideration in use.

 

[TalonArms_R]

MV,
I have a little experience with shorty ARs....

Both versions of SBR are fun, but as has been said before, a 9mm is better suited as a range toy than a defensive weapon. I have built quite a few and have yet to find one reliable enough to stand behind with lives on the line. On the range though, they are fun!

The 5.56mm will give you better reliablity (providing you use a quality upper, BCG, mags and ammo.) than the 9mm will and anything 10.5" or longer will work well with a can with no baffle strikes. It also gives you better terminal ballistics at longer ranges. My 11.5" SDI Commando with Gemtech G5 is a weapon I would never feel under gunned with.

In the end, I am glad I have both.

 

[shappy0869]

This is an affordable choice too...

I am sure M2_Carbine will chime in one this.

 

[TexasRifleman]

My home defense rifle is currently an 11.5" 5.56 AR. I am debating a Gemtech suppressor, but have not decided yet. Frankly I like the shorty for it's handling, though I recognize the extreme noise level if I ever had to use it without hearing protection.

--Loud, huge muzzle blast - The Noveske Krink FH does work VERY well in redirecting all this.

--Gas-cycling issues - None whatsoever, over 2500 rounds.

--Can use a Noveske to redirect the noise, but tricky to use with cans b/c of likelihood of baffle-strikes - You'd remove the Krink FH with a suppressor anyway.

--Notable loss of velocity - I'm shooting Hornady TAP .223 so that isn't a problem anyway.

 

[shark3-1]

Baffle strikes are not a problem in barrels longer than 10". This is assuming your not completely retarded and shoot 77gr rounds out of a cut down barrel with a 1-12 twist (in which case the barrel could be 16" and you would probably still get baffle strikes).

The only concerns you should have with a 5.56 suppressor on any of the factory built shorties (LMT, Colt, Bushmaster, RRA, CMMG, Noveske, Compass lake, etc. etc.) is heat and erosion.

FWIW, the krinks are really heavy and LONG for what they do. You can get a short CQB suppressor that would be about an inch longer and not much heavier. If a suppressor is not available to you, I would use a regular flashhider to keep the weapon light and short. The main benefit for running the krink is increased gas pressure on finicky guns. YMMV

 

[TexasRifleman]

FWIW, the krinks are really heavy and LONG for what they do. You can get a short CQB suppressor that would be about an inch longer and not much heavier

Comparison of the Noveske new model Krink and a Gemtech M4-02 (a leading CQB suppressor)
A little bigger difference than you'd think.


Noveske KX3
7.2 ounces
3.28 inch OAL

Gemtech M4-02
16 ounces
6.25 inch

 

[shark3-1]

Noveske KX3
7.2 ounces
3.28 inch OAL

Gemtech M4-02
16 ounces
6.25 inch

I did overexaggerate the length and the weight, but what I was trying to convey is that the Krink doesn't do much of anything and is heavy and long. The can, while it is heavier and longer actually does something usefull.

I have owned 2 KFH and 2 KX3, I bought them because I thought they would have some kind of advantage in reliability and/or reduced noise to the shooter or others nearby. I found them to be a paperweight that has no real advantages when you already have a reliable weapon. It certaintly doesn't work well as a FH in my experience.

IMO, if you are going to stick something on the end of the SBR that increases the length and the weight, it should be either more barrel, or a suppressor. I think that people buy them because they think that it will negate the need for earplugs indoors or help protect others hearing indoors by directing the blast, I still go temporarily deaf when I fire a KX3 equipped rifle indoors or if I'm in the same room when it is fired. Hell, my ears almost ring when I fire a rifle indoors with a full size rifle can on it.

I'm not trying to tell you you made a bad decision, I'm just telling you what my impressions of the device are. You are correct about the length and weight of both a CQB can and a KX3.

 

[BucksDC]

Hello

I have a kitty-kat bbl'ed AR (7inches) with Noveski break, and it runs like a champ. Over the last two weeks I have put about 500 rounds of Winchester, Wolf and Silver Bear thru it without cleaning, and it still runs. I am trying to see how long it can run uncleaned. The Silver Bear (200rnds) really started to slow the action up. Making it hard to charge, almost a sticky feeling. It has a good concussive whoomp out of the short bbl, but the break dampens the shooter perceived loudness. I couldn't tell you about knockdown power or ballistics, but no cardboard has walked away, even at 100 yds. At 100 yds I am getting about 5-6inch 10rnd groups off sandbags. This is with iron sights and the short sight radius. I am eager to see how much I can shrink those groups with an aimpoint.
My next SBR will be a shorty AR in 9mm. I have an MP5 clone, and when it runs, it is a blast to shoot. A big plus is that I can use it at my range's pistol pits with steel targets in various scenarios. I can't do that with rifle calibers. Our rifle range is standard set up, shoot at a known distance into paper.

IMO the choice comes down to ammo money and range rules. Any SBR has a coolness factor. Any would suffice for a SHTF scenario that I might be involved in. I really enjoy the .223, but my enjoyment is dampened by the money flying downrange. 9mm is easier to stomach.

 

[TexasRifleman]

I found them to be a paperweight that has no real advantages when you already have a reliable weapon.

Well we can respectfully disagree on that one.

I find, from the shooters perspective, that there is a HUGE reduction in blast and noise vs a standard FH or the Phantom I had on before that.

VS. my 16" M4 I think that the perceived blast for the shooter is still less with the shorty.

Also, the folks I shoot with regularly said they could stand to be next to me on the firing line now where with the Phantom I had to walk off alone

But I do agree that a suppressor is best, though I'm looking for as short as possible so I don't give up the handling advantage of the short barrel.

9mm is easier to stomach.

Something to consider for sure. I might get a 9mm upper for mine at some point.

 

[M2 Carbine]

However, the more I've heard about shorty AR's, the more problematic they seem. My (chairborne-commando) impression of .223 7"-11" ARs:
--Loud, huge muzzle blast
--Gas-cycling issues
--Can use a Noveske to redirect the noise, but tricky to use with cans b/c of likelihood of baffle-strikes
--Notable loss of velocity, though not as bad as some folks imply


Given those issues, would a 9mm shorty be just about as cool for plinking and gaming? Maybe 7"-10" barrel,
Does a .223 11" AR still greatly exceed the 9mm AR in terms of useful range, and general ballistic utility?

I don't have any shorty AR's but I do have a couple .223 Kel Tec PLR's and a Bushmaster Carbon 15.
The PLR has a 9 inch barrel and the Bushmaster's barrel is 7 inches.

I have a 16 inch barrel UZI which has a muzzle velocity of 1306 fps. The 9mm MV from a 7-10 inch barrel is going to be close to 200 fps slower.

The muzzle velocity of the .223 is 2,515 fps from the 9 inch barrel and 2,296 fps from the 7 inch barrel.

IMO the 9mm in almost every way is inferior to a .223.

The .223 bullet in the 2,500 fps range will go through 1/4 inch steel plate, the 9mm, even in a longer barrel will hardly scratch 1/4 inch steel.

The .223 at any distance is more accurate than the 9mm. My PLR gives me 100 yard groups as small as 1 1/8 inch and 2-2 1/2 inch groups are normal.
I don't know but I doubt the average 9mm shorty AR does that.
I haven't shot the (AR) Bushmaster Carbon 15 enough at 100 yards enough to get a good idea what it is doing at 100 yards but I'm sure it is more accurate than a comparable 9mm shorty.

The short barrel .223 isn't loud, it's horrendous.
A 9mm is fairly quiet.

The muzzle flash from a short barrel .223 is about the size of a 5 gallon can and VERY impressive.
But the flash can be almost totally stopped with the right flash hider.

About the only thing I can think of that the 9mm has over the .223 is the cost of the ammo.

I don't know about the reliability of the average shorty AR but my Bushmaster does fine.

This is all not to say that I wouldn't like to have a gun like the PLR chambered in 9mm.

Here's a few pictures of the short barrel .223 in action.

Kel Tec PLR and Bushmaster Carbon 15.


1/4 inch steel shot with the 9 inch barrel .223. The 9mm chips the paint.


Short barrel .223 muzzle flash with plain barrel.


Same PLR a few minutes later with a Phantom flash hider installed.


Accuracy of a good short barrel .223.

 

[shappy0869]

This is a bit off topic, but related to a SB .223. With such short barrels, doesn't muzzle velocity almost immediately fall below the 2700 fps magic number desired for fragmentation?

If you are using it in anger, aren't you basically just punching .22 cal holes into whatever (or whomever) you are hitting?

 

[Correia]

shappy,

Once .223 hits 2,500 fps, it falls out of the air, and lands on the ground. Helpless... So helpless...



Seriously, those of us using SBRs for home defense aren't limited to the same ammo in Black Hawk Down. There are plenty of loads ou there that perform a whole lot better than a .22, even well below that magic 2,700 number.

 

[TexasRifleman]

If you are using it in anger, aren't you basically just punching .22 cal holes into whatever (or whomever) you are hitting?

Depends on your barrel and ammo.

Out of my 11.5", XM193 keeps above 2700 out past at least 50 yards.

That said, most people using these for real are using 75gr Hornady TAP or a 77gr Mk262Mod0 variant ammo anyway, which doesn't need the "magic 2700". I'm not subject to the Hague Accord. Both of these use the OTM (legal speak for hollow point LOL)

I use the .223 TAP.

 

[M2 Carbine]

shappy0869
This is a bit off topic, but related to a SB .223. With such short barrels, doesn't muzzle velocity almost immediately fall below the 2700 fps magic number desired for fragmentation?

If you are using it in anger, aren't you basically just punching .22 cal holes into whatever (or whomever) you are hitting?

I'm not real concerned with fragmentation in a civilian gun.
Why use FMJ in a defense gun when you can use JSP.

A Remington 55gr JSP shown with a 45ACP Gold Dot.
This .223 bullet was only loaded to about 2,300fps and shot from the 9 inch barrel PLR.

 

[shappy0869]

Good info, thank you all.

 

[ny32182]

My impressions based on my LMT 10.5" 5.56mm:

--Loud, huge muzzle blast

90 degrees from the muzzle, the blast is HUGE. Much louder than a 16". As the shooter, I can't tell a difference in terms of the noise, but the 10.5 has a much greater flash as well that is clearly more noticeable from any perspective including the shooter's. My rifle has a standard A2 FH on it.

--Gas-cycling issues

My rifle hasn't malfunctioned, but I have cleaned it after every 100rds or so, and it clearly gets dirtier faster than a 16". That is a result of the larger gas port. The larger gas port also speeds the cyclic rate, which makes the internals wear faster as well. If I had to guess the round count on my 10.5"'s bolt, I would definitely have overestimated it. Looks like a bolt from a 16" with a considerably higher round count. Overall its a higher strung/higher stressed action. Definitely use an MP tested bolt.

--Can use a Noveske to redirect the noise, but tricky to use with cans b/c of likelihood of baffle-strikes

I don't have a can yet, but have researched getting one, and baffle strikes shouldn't be considered a problem on barrels over 10" or so.

--Notable loss of velocity, though not as bad as some folks imply

Muzzle velocity with 55gr should be right around 2700fps or so.

Given those issues, would a 9mm shorty be just about as cool for plinking and gaming? Maybe 7"-10" barrel, no gas issues with the blowback mechanism, collapsing stock, put a nice big can on it too balance it out and get max suppression, etc. I've seen some sub-sonic .44Mag bolt-rifles that sounded "movie quiet", so I'd hope that a 9mm subsonic rifle with a good can would also be extremely quiet.

Does a .223 11" AR still greatly exceed the 9mm AR in terms of useful range, and general ballistic utility?

You are still comparing a rifle round to a pistol round. The difference is ballistic performance is vast. Shooting a 10.5" AR feels about like shooting any other AR to the shooter. The few times I shot 9mm carbines, it literally reminded me of shooting a paintball gun: virtually no recoil or movement of the gun at all.