Kel-Tec RDB: A Unique Bullpup Rifle Design

by
posted on December 9, 2020
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
kel-tec-rdb.jpg

To say the Kel-Tec’s RDB is an unusual take on a bullpup is understatement. The firearm’s initials—which stand for Rifle, Downward-Ejecting Bullpup—tell only part of the story. It was a big hit at the NRA Annual Meetings & Exhibits in 2014, where it was first unveiled to enthusiasts.

Bullpup designs traditionally eject up top or compromise ambidextrous use by tossing empty cases to one side or the other. In this rifle they leave from behind the magazine well and head toward the ground. The piston-driven RDB is semi-automatic and uses a short-stroke, gas-operattion system.

Versatility is key in the gun, and includes a regulator on the barrel that allows owners to adjust the amount of pressure tapped off for cycling (for suppressor work or when using light loads). It’s also modular, consisting of four assembly groups—bolt group, barrel group, grip group and where the serialized component resides, the receiver group. H&K-style push pins make disassembly for maintenance, repair or replacement fast and easy. Dual ejectors on the bolt ensure operation from unconventional shooting positions, even upside down.

All four versions available today are chambered in 5.56 NATO, feature 1:7" rifling, have a rail on top for optics and accept standard AR-15 magazines. That’s a huge advantage for enthusiasts who already own a modern sporting rifle.

Last year the Kel-Tec RDB was the seventh-most-poplar semi-auto rifle in sales on GunBroker.com. It’s gaining steam, too, because it was No. 8 in 2018.

You can expect it to move up in the rankings when this year’s totals are in, thanks to the company’s introduction of the new Defender RDB model. Its barrel is 16.1" in length, the buttstock is adjustable and it comes with an M-LOK-compatible aluminum handguard. MSRP is $1,072 to $1,142, depending on options.

The RDB Defender version has the same length barrel, but ships with folding sights and no pistol grip. Price varies from $1,036 to $1,108.

If you’re after hogs or hoping to fill a tag on opening day the Hunter model may be more to your liking. With a sleek fore-end, 20.5" barrel and swivel stud up front, expect it to set you back $930 to $1,002.

And finally, the RDB 17 wears a 17.3" barrel. It has a Zytel fore-end, Pitatinny on the bottom for accessories and MSRP is $930.

Latest

Us Army 250 Th Part 3 1
Us Army 250 Th Part 3 1

250 Years of the U.S. Army: Bolt-Actions & Semi-Automatics on the Battlefield

In just a few decades, the U.S. Army would see itself go from a single-shot, blackpowder design in the form of the Trapdoor Springfield to a modern, semi-automatic fighting rifle in the M1 Garand.

Modernized & Economical Muzzleloaders: The CVA Optima XP & XP-SB

CVA's longest-lasting muzzleloader design, the Optima, has been updated in 2026 with "modern ergonomics and modularity."

MidwayUSA Awards $7.5 Million in Cash Grants to Support Youth Shooting Teams

MidwayUSA Foundation recently announced that it concluded its most recent grant cycle, which resulted in a total payout of more than $7.5 million to youth shooting teams and organizations nationwide.

The Constitutional Concealed Carry Reciprocity Act is on the Move

The story of American freedom, now almost 250 years on since delegates to the Second Continental Congress signed the Declaration of Independence, leads irrevocably to the Constitutional Concealed Carry Reciprocity Act.

Mixing & Matching Gun Parts: What’s The Catch?

How would one about verifying that parts from one gun would fit and function on another of the same make and model? What about aftermarket parts sold as replacement parts for hard-to-get original parts?

U.S. Army & Navy Award FN a $9.9 Million Contract for Machine Guns

FN America has been awarded a $9.9 million contract to supply the U.S. Army and U.S. Navy with FN M240B machine guns, continuing the supply of FN America’s longest-standing military weapons platform.

Interests



Get the best of American Rifleman delivered to your inbox.