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

Ihtog Walther P38 1
Ihtog Walther P38 1

I Have This Old Gun: Walther P38

On the eve of World War II, the German military sought a new sidearm that was easier to manufacture than the P08 Luger. Its answer was the P38.

C&H Precision STRYKR: A Red-Dot Sight for PDWs

The C&H Precision STRYKR is a hard-use, enclosed-emitter optic designed for PDWs and compact carbines.

Rifleman Interview: Smith & Wesson M&P15-22 OD Green Topographic Rifle

At “Plinkapalooza” in May we had a chance to try out the latest Smith & Wesson M&P15-22 rifle.

Patriots Landing Announces "A Nation Remembers" Veterans Weekend

Patriots Landing, a faith-based veterans workshop based in Kentucky, announced it would hold "A Nation Remembers" veterans weekend in Grant County, Ky., from Sept. 16-20.

Past NRA President Allan Cors, 1936-2026: Liberty Takes A Loss

One of liberty’s champions, past NRA President Allan D. Cors died on August 10, 2026.

Moving to the Micro Red-Dot: An Old Dog Learns Some New Tricks

After shooting open-sighted handguns for more than 40 years, the author's aging eyes finally caught up to him, and his concealed-carry pistol now sports a red-dot optic.

Interests



Get the best of American Rifleman delivered to your inbox.