The bulk of our evaluations at Gun Tests consist of head-to-head match-ups of like weaponry. However, every once in a while we come across firearms that occupy such a small niche, that competing products are hard to find. The best that we can do is match them up by job function, and see which product we prefer.
The job this month is long-gun self defense. The Kel-Tec SU-16 is, for all intents and purposes, a lightweight AR-15 that folds in half.
The Kel-Tec SU-16 version of the AR-15 rifle featured a barrel and mechanism composed of 4140 steel, but the remainder of the gun was constructed of DuPont Zytel, or reinforced polymer. The forend could be unlatched, splitting in half to drop down and form a bipod. We found that the amount of support this bipod offered was not rock solid but it was helpful when used in conjunction with additional support. For this reason our accuracy tests were performed with the forend locked into the traditional position. However, when we received the SU-16 we had difficulty locking both halves of the forend into place along the barrel. We were finally able to seat the forend by removing material along the edges where the two pieces met. The magazine release was in the familiar position just ahead of the trigger guard on the right side, but the safety and the charging bolt varied from standard AR-15 design. The safety was a crossbolt assembly mounted above and to the rear of the trigger guard instead of being available to the thumb on the left side of the weapon. The safety was hollow on the right side and capped on the left side. (Safety off required pushing the bolt right to left). The charging mechanism was a simple bar operating just above the magazine well on the right side.
Kel-Tec did a good job of adding grip to the slippery polymer and creating tactile clues for the safe operation of this carbine. The forend, pistol grip area, and the sides of stock toward the butt were textured with useful checkering. The magazine release, however, was left smooth, and we found it to be lost among other nearby raised surfaces. We would have preferred a checkered magazine release to prevent the index finger from slipping off into the trigger guard.
Overall length of the SU-16 measured 37.5 inches with a maximum height of just over 7 inches. Folded for storage, the SU-16 became a package measuring 26.2 inches long and approximately 7.5 inches in height. Weight was 6 pounds with the two supplied polymer magazines stored (empty) in the underside of the stock. The SU-16 will also operate from standard AR-15 magazines. Kel-Tec claims this same storage space is compatible with either a single 20-round or 30-round magazine, but we couldn’t get a 30-round magazine to settle into this compartment. We found that a 20-round magazine could be stowed, but the resulting fit wasn’t ideal.
To fold the SU-16, we removed a single pin in much the same way that disassembly begins for an AR-15. But in this case the pin must be completely removed. Once folded, loss of the pin is prevented by slipping it back into the channel on the top end. A wire retainer mated with grooves in the pin kept it in place. It might be wise to keep an extra pin on hand.
The sights on the SU-16 consisted of an oversize aperture rear sight that was mounted on the Picatinny rail and a hooded front blade that sat about 2 inches above the muzzle. The front sight can be moved left and right to change windage and up or down to effect elevation. The manual provided exact information regarding how much the sight was to be moved versus the resulting change in point of impact. The rear sight can be moved forward or back, resulting in a change of sight radius that would further change elevation. However, in our opinion, the locking pin was seated so tightly into the rail that attempting to remove it would cause irreparable damage to the pin, the sight, the rail or all three. So, we decided to leave it in place and live with the original point of impact, which at 50 yards turned out to be about 10 inches high.
Our test ammunition consisted of 62-grain FMJ rounds from Federal American Eagle and Winchester USA. Our third choice of test ammunition was a remanufactured load by Georgia Arms (770-459-5117) that featured Winchester cases and a 55-grain FMC bullet. Average velocity was topped by the Federal rounds that moved at 2919 fps and produced the most muzzle energy of 1174 foot-pounds. The sights proved to be as clear as they were simple, and we rated the 6-pound trigger as acceptable in terms of feel. Since each of the carbines was designed for high-capacity magazines, we dispensed with the practice of measuring mere three-shot groups. Instead, we fired five-shot groups, just like we would a pistol. Results from a sandbag rest met our expectations for this little folding carbine. We landed the most consistent groups in combination with the Federal American Eagle rounds, with little variation from the average measurement of 2.2 inches per five-shot group. The Georgia Arms rounds, which have scored well in the past with other rifles, managed a 3.0-inch average group, and the five-shot Winchester groups varied from 2.3 to 3.0 inches in size.
To improve this performance and simplify adjusting the point of impact we thought that the best bet would be to simply top the SU-16 with a scope. Our first choice would be the Sightron S33-4R scope, because it offers excellent light and a choice of four different reticles, ($233 from Brownells, 800-741-0015). But, any number of dot scopes would likely be up to the task making the Kel-Tec SU-16 even more appealing.
The only question left in our minds was durability of this folding gun. We opened and closed the SU-16 repeatedly in an attempt to disrupt alignment, and we fired over 250 rounds through it without the benefit of lubrication. So far we have not seen any hint of malfunction.
