As part of my personal HDI (Homeland Defense Initiative) I've looked over some "safe queens" to see if they can earn their keep in a bailout bag or backpack. Lo and behold!, I bought the item below in 1997, fired it once (it was fun), put it in the vault, and then forgot about it until I stumbled across some mention of it on some gun site. It's a Kel-Tec Sub9 (now replaced by the Sub2000) 9mm folding carbine.
I discovered that the Sub9 is somewhat of a collector's item, because it had too much machining in it, so Kel-Tec modified the design to use more plastic, coming out with the Sub2000 in 1999. It's still in production today, and if you want a $300 carbine or camp gun in 9mm or .40S&W, it's a handy item, especially if you get the grip adapter to match your handgun. It can use Glock, S&W, or Beretta mags, depending on the adapter.
Here's my final result, after installing accessories from Kel-Tec (soft case and dust cover) and Tacticool (neoprene tube cover, cocking handle cover, and recoil buffer.
It uses S&W 659 mags, and a left-over Urban ERT sling. The GI mag pouch will be replaced shortly with something that works better with the PALS loops on the sling. And it even takes aftermarket 30-round S&W mags.
A closeup shows how the longest part is the 16.1 inch barrel. That makes the assembled weapon longer than the 30-inch federal minimum, but shorter than 32-inch Michigan long gun minimum. When I bought it, it was so new that some dealers sold it as a handgun, and others as a long gun. I bought mine (two-digit serial number) as a long gun. I didn't even know it existed until I saw it at a gun show, and stopped in my tracks to study it.
Being a straight-blowback design, it fires unlocked from the closed bolt position. It was pleasant to shoot because of its mass (a straight-blowback Astra 900 was the nastiest handgun I have ever shot), but I went with the Tacticool recoil buffer to smooth things out even more. I hope it will also let me use the hot IMI 9mm submachine gun ammo I have hoarded for all these years.
I wasn't too happy with the sling setup I got from Kel-Tec, so I decided to improvise. The "front swivel" is actually intended to screw to the left side of the rear sight housing, with the rear of the sling being wrapped around the slot in the stock. Instead, I took off the unneeded Midwest Industries M4 swivel adapter off the Mossberg, and adapted the stock to use it.
I clamped the "MI" side of the adapter in place, then drilled two holes to allow the adapter to be clamped together. I carefully thinned down the front sling swivel on a disk grinder (I did melt the edge of one fingernail, but didn't lose any skin) so that it would fit in the front slot of the foreend, where a short rail mount can also go. It doesn't swivel, but it was the only part of the Kel-Tec sling kit I wound up using. But I'm much happier with my own setup, so it wasn't a total loss.
Another Kel-Tec accessory is the action cover, designed to close things off when the weapon is folded. It's plastic, with two long "fingers" that hold it inside the action. Swinging the barrel into the unfolded position squeezes the fingers, and shoots the cover about ten feet. The weapon is folded by swinging down the trigger guard, which hinges at the front.
Finally, a look at the two "comfort" items from Tacticool that makes the Sub9 more user friendly. One is the neoprene action tube cover. The tube itself is steel, and is always too hot or too cold. They left the cover length untrimmed, because I was the first Sub9 owner to buy a cover, and the length of the steel tube is a bit shorter on the Sub2000. It worked perfectly. And the semi-hard plastic cover for the charging handle makes operating it more comfortable than the series of ridges and disks machined into it, as shown in the Sub2000 picture.
After spending some quality time with the Sub9, I took out a scale, and found out that the Sub9 with three loaded mags weighs the same as the Armalite AR-7 with 500 rounds of .22LR. Bullets are heavy, and the question becomes whether one wants a .22 with 500 rounds of ammo, or a 9mm with 45 rounds, all for the same weight penalty.
Still, it's a fun weapon, and the Sub2000 is well liked when used within its design limits. But nothing beats the absolute blast the comes with firing the FN PS90. But the Sub9 is something I can put in a bailout bag and forget about it. I'd already forgotten about it for almost ten years now, anyway. It won't stay forgotten than long again.