I own two of these neither fish nor fowl carbines. They have nowhere near the range of a “real” carbine, nor are they concealable like a pistol, so what is their appeal? I actually think they have a couple of things going for them, and in civilian life very little downside.
These carbines share the advantage of all rifles, multiple points of contact (shoulder, 2 hands & cheek) provide greater stability. It’s longer barrels give a bit of a velocity boost, and in 9mm makes for a 200 yard rifle or so.
On my AR carbine I have and Eotech XPS 2-2, that has 2 dots (1 MOA when turned down) in a non-magnified holographic reticule. The center dot lines up with 25/100 yards and the second perfectly with 200 yards, when I shoot the very cheap and fairly effect 9BPLE 115gr +P+ defensive round.
The 9mm is more than accurate enough for the ranges we are talking about. The paper plate below was shot off hand at 25 yards, maybe a 5 MOA group from standing ain’t too bad. I believe that a 3 MOA group from prone with a sling with decent ammo would not be too challenging.
Weight & Size
The Kel-Tec SUB 2000 is exceedingly light at 4 lb and 16 inch long when folded, it fits nicely in an old laptop bag and makes an easy “truck gun” to store. The AR-15 in 9mm runs roughly the same as it’s .223/5.56 counterpart at ~6 lbs. My rifle has a pencil barrel, short hand guard and a minimist stock to keep the weight down.
Gun Range Usage
My range only allows center fire rifle rounds in a few places, but pistol calibers are allows everywhere, even if it’s launched from a 16 inch barrel. So a AR in 9mm can become a trainer for your full powered AR-15 and most of the controls work the same. My carbine does not have a bolt hold open, but that is an option if so desired.
A 9mm carbine provides a surprising amount of recoil, offering a more realistic training experience than the .22LR understudy. Both carbines are sufficiently accurate to easily hit a paper plate off-hand at 100 yards all day long with either a red dot on the AR, or a 5 MOA post on the Kel-Tec (my front sight has been replaced by a metal sight, replacing the plastic factory part) and a pretty generous rear aperture. The trigger on the Lone Wolf lower that came in it is surprisingly good, but of course it can be replaced with any AR-15 trigger you wish. Some 9mm lowers need a “rounded hammer” to work properly, but the Lone Wolf is not one of them. The Kel-Tec trigger on the other hand is very heavy, 10 lbs or more, and the original plastic part would flex under the strain, so I replaced it with a metal part, but it’s still pretty terrible, but it does not seem to effect making good hits out to 100 yards (but 8 MOA is not exactly sniper grade). The lack of the bolt hold open on either rifle is their biggest downside, for the AR-15 it makes it a less good training understudy for the AR-15 in a rifle caliber. The Kel-Tec has it’s magazine well in the grip, just like a semi-auto pistol and it makes for a very sure and nature reload, even in the dark. The idea that “hand finds hand” which was a design principle in the Uzi is also at work with the Kel-Tec.
Most, but not all Glock compatible magazines work in both the AR and Kel-Tec carbines. The ETS, Glock and Magpul all work flawlessly in both rifles, but the Khan (Korean) will not fit in the tighter magazine well of the the AR-15. All types do work in the more generous magazine well of the Kel-Tec. I’ve had almost no problem with either rifle feeding and ejecting just fine. These rifles shine with a 33 round “happy stick”, and both ETS and MAGPUL have or are releasing 22 and 27 round magazines that are IDPA legal at 140mm and 170mm, respectively.
Looking at ammoseek.com (10/7) .223 is 21.8 cents around verse 14 cents for 9mm. Both are steel cased Tulammo, but on a well build gun they should run fine, with maybe the occasional short stroke, since Tulammo is at the low end of power. So basically you can put 3 rounds of 9mm in the berm for every 2 you could in .223 for the same price. If you already own a Glock, the cost of magazines and magazine pouches can be shared between your pistol and carbine. If the “cowboy” advantage of having just a single caliber to stock and keep track of is an avantage to you that is great, but for most of us 223 and 9mm are both calibers that we stock.
There is a concern about 9mm penetrating normal house building matters. This may be true, but there is also some testing that says just about any round will over penetrate most American homes. A 115gr hollow point seems like it would be the most likely to penetrate the least, but that is only conjecture and if this is a major concern you could use a frangible or speciality round like the Glaser Safety Slug by Corbon
I use the ITOA bag by Hawkepaks, that has 4 Glock 22 round magazines from ETS and a VOK Trauma Kit which pairs well with either of these rifles or my CCW Glock and keeps medical supplies and ammo right where you need it.
Some guns are fun. Not every gun needs to be used to hunt or be setup for the blue helmets, some are just to fun, and both these guns are that in spades, from easier magazine handling (compared to 5.56 or 7.62), lighter and cheaper, for a little “run and gun” at the local outdoor range that allows that kind of thing.