I’ve had a bit of experience with bullpups, some more than others. But if you’re interested enough in them to be reading this, you may want to read my last piece “Ode to bullpups” where we discussed bullpups in general. Today we will be speaking specifically about the Keltec RDB bullpup, a sixteen inch barreled 5.56 bullpup semi-auto.
Keltec has been around since the early nineties, with a motto of creating original and innovative firearms in the state of Florida. An overview of Keltec firearms gives the impression that affordability, alternative designs and materials are all part of their operation. My personal experience with Keltec has been modest at best until this RDB came to me, so this review will represent a fresh look at the rifle.
The RDB is a 5.56 nato chambered bullpup rifle, the action and magazine are located behind the pistol grip. This allows the rifle to present with a much shorter and well balanced platform than a traditionally configured rifle such as an AR-15. The RDB is fed by standard AR type magazines, and those cartridges are loaded by a piston driven bolt-carrier. The sixteen-inch one in seven twist barrel features a 1/2-28 threaded muzzle that came with a birdcage style muzzle device, as well as an adjustable gas block to meter pressure into the operating system. The cunning ejection system that sets the RDB apart from its competition is it downward ejection, the spent cases are pulled behind the magazine and ejected out the bottom of the rifle. The controls of the rifle are pretty standard, but not like you are used to for sure. There is a reversible charging handle that can be placed on either side of the fore-grip after disassembling the rifle. The safety is ambidextrous and located in the right position, right where your thumb would expect it to be.
The magazine release and bolt catch are both located behind the pistol grip. The mag release is a stamped piece of metal that reaches around both sides of the lower-rear receiver, there is a push-pad at the front of this horseshoe shaped piece just behind the pistol grip to release the magazine. The rifles locks open upon emptying the magazine, and the bolt release is located on either side of the lower receiver, but uses a captured lever on the right side of the rifle to aid in leverage to easily release the bolt after loading a fresh magazine.
There is a picatinny rail across the top of the rifle for sight mounting, and there are several points on the rifle for attaching slings with a hook or other attachment. The Defender handguard features M-Lok slots at three, six, and nine o’clock for attaching additional accessories.
I have seen Keltec firearms for years and had many opportunities to handle them. So when the RDB case arrived I wasn’t particularly surprised by its contents. I picked the RDB up from its case, and cleared it for inspection. I shouldered the rifle to give it a feel, it was then that I noticed it was lighter than I had anticipated, six-point-seven pounds according to Keltec. This was a pleasant discovery.
I played with the rifle for a few minutes to get a full understanding of its operation and features, and then I stared at it for a bit. At first I thought it appeared like a high school or college engineering class had drawn this thing in Solid Works, but the more I looked the more I could see what they were working at. The bullpup balance was like most others I’ve held, balanced right at the grip area. I again ran the charging handle a few times, the handle can be pulled to the rear and lifted into a locked position to leave the action open. But the ejection port being on the bottom, there isn’t really a place to inspect.
I wanted to try out the trigger, which for many bullpups is famously terrible. To my surprise the trigger was not bad, the first stage gave way to a solid wall that broke clean and firmly. So firmly in fact I almost immediately felt the desire to open up the rifle and see what was making such a significant strike when I pulled the trigger. Internal inspection showed a very curious design, both the hammer and trigger mechanisms were far from what I’d imagined.
The hammer itself is not unlike a turkey wishbone, with two legs coming together at the top to form a hammer anvil. The hammer splits around the magazine well, and the sear/connecting linkage travel all the way up to the trigger group itself. The whole thing is quite interesting, and explains why the trigger feels so good compared to other bullpups.
While inside I noticed the very short bolt carrier. The bottom ejection requires the bolt-face to travel far enough behind the magazine as to allow spent cases to clear the magazine and trigger parts. The short bolt and firing pin are similar to most other semi-auto bolt designs, with a rotating bolt guided by a cam-pin that also locks into the receiver guide rails as it goes into battery.
With fresh perspective, I reassembled the rifle and went to work preparing it for a range session. The rifle had come with set of Magpul flip up sights, but I also added a Sig Sauer Romeo RDS. I was surely going to try the rifle suppressed as well, to see how the adjustable gas system could accommodate the difference.
On the Range
Once on the firing line, with some thirty-round magazines I loaded the RDB and prepared to fire. Initial ergonomics were not bad, the rifle fit me well. The charging handle on the left side of the rifle was easy to find blindly and provided plenty of purchase. With an easy click of the safety I was in business. Recoil was just what I expected from a 5.56 caliber bullpup, not bad at all. The spent shells began to pile up neatly on the ground in front of me. When my first magazine went empty, it was time to try out the reloading controls of the rifle. Stuffing magazines through the rifle and doing lots of reload drills taught me a couple things about the RDB. It could use a more flared magwell, as it seemed a little bit of a stickler to get the magazine stabbed in properly. The magazine release worked better than I had anticipated, almost too good. I have long heard of people complaining that the mag release is too easy to inadvertently drop the magazine while maneuvering the rifle. And it proved to be so for me as well, a slight miscalculated move of the shooting hand can drop your magazine from the rifle. The bolt release took some time to get used to as well, reaching back and hitting it with my right thumb seemed to be the best option. I’m sure with some training it could become second nature. Cross training on different rifle platforms doesn’t hurt anyone, and its a bit of a pet peeve of mine when bullpup haters act as though a slight retraining in operation somehow renders a gun “useless” in their opinion. Continue Reading Here…