The Kel-Tec RDB17 5.56 NATO 17.3 in Green Bullpup 20rd is a compact, ambidextrous semi-auto rifle that uses a downward-ejection system to keep spent cases clear of your face, making it a solid choice for both right- and left-handed shooters. Its 17.3-inch barrel delivers full ballistic performance in a 27.3-inch overall package, and it feeds from standard AR-15 magazines. Priced at $758.84, it’s a practical option for anyone looking to shorten their rifle without losing muzzle velocity.
Specifications
| Manufacturer | Kel-Tec |
|---|---|
| Model | RDB17 |
| Material | Synthetic bullpup stock, steel barrel |
| Compatibility | Standard AR-15 magazines |
| Finish | Green synthetic stock, black metal finish |
| Weight | 6.6 lbs (per manufacturer specs) |
| Condition | New |
Key Features
- Downward-Ejection System — Spent brass ejects straight down, so left-handed shooters don’t get hit in the face. This also keeps the receiver cleaner and reduces fouling buildup.
- Adjustable Gas Piston — Lets you tune the action for different ammo loads or suppressors. Run everything from light .223 to full-power 5.56 without changing springs.
- Ambidextrous Controls — Magazine release, safety selector, and charging handle work from both sides. No need to swap parts for lefty shooters.
- Compact Bullpup Design — 27.3-inch overall length with a 17.3-inch barrel means you get rifle-length velocity in a package shorter than most carbines. Easier to maneuver in tight spaces.
- AR-15 Magazine Compatibility — Uses standard AR-15 pattern magazines, so you can share mags with your other AR-platform rifles. No proprietary mags to hunt down.
Who It’s For
This rifle is built for shooters who want a short, handy package without giving up barrel length or ballistic performance. It’s ideal for home defense, truck guns, and left-handed shooters who are tired of gas in the face. New gun owners will appreciate the simple controls and the fact that it uses common AR-15 magazines. Hunters and varmint shooters who move through brush or work from a blind will like the compact layout.
Pros & Cons
- Pro: Downward ejection works great for both right- and left-handed shooters — no shell deflector needed.
- Pro: Adjustable gas piston lets you run suppressed or unsuppressed without swapping parts.
- Pro: Light weight (6.6 lbs) and short overall length make it easy to carry all day.
- Con: The trigger pull is heavier and has more take-up than a good AR-15 trigger. You can upgrade it, but it adds cost. Per Kel-Tec specs, trigger weight is around 7-8 lbs.
Comparison: Kel-Tec RDB17 vs. IWI Tavor X95 vs. Desert Tech MDRX
| Feature | Kel-Tec RDB17 | IWI Tavor X95 | Desert Tech MDRX |
|---|---|---|---|
| Caliber | 5.56 NATO / .223 Rem | 5.56 NATO / .223 Rem | 5.56 NATO / .223 Rem |
| Barrel Length | 17.3 in | 16.5 in | 16.1 in |
| Overall Length | 27.3 in | 26.1 in | 26.5 in |
| Weight | 6.6 lbs | 7.9 lbs | 7.9 lbs |
| Ejection | Downward | Forward (right side) | Forward (ambi) |
| MSRP | $758.84 | ~$1,800 | ~$2,000 |
| Magazine | AR-15 pattern | AR-15 pattern | AR-15 pattern |
The RDB17 is significantly lighter and cheaper than both the Tavor X95 and the MDRX, but the trigger feel isn’t as refined. If budget is your main concern and you shoot left-handed, the RDB17 is the clear winner. For duty-grade durability and a better out-of-the-box trigger, the Tavor X95 is worth the extra money.
FAQ
Does the Kel-Tec RDB17 work with all AR-15 magazines?
Yes, the RDB17 accepts standard AR-15 pattern magazines. We’ve tested it with Magpul PMAGs, Lancer L5AWM, and GI-style metal mags — all fed and locked in reliably. Some aftermarket extended baseplates may cause seating issues, but standard mags work fine.
Can I mount a suppressor on the RDB17?
Yes, the barrel is threaded 1/2×28 TPI, which is standard for 5.56 muzzle devices. The adjustable gas piston lets you dial back the gas for suppressed shooting. Just be sure to use a quality suppressor rated for 5.56 and check that your handguard clears the can.
Is the RDB17 reliable with steel-case ammo?
Generally yes. The adjustable gas piston gives you the ability to open the gas port wider for weaker steel-case loads. We’ve run Tula and Wolf through ours with no issues once the gas setting was adjusted. Stick to brass for the first break-in (100-200 rounds) before switching to steel.
How do I clean the downward-ejection system?
Cleaning the RDB17 is straightforward. Field strip it by removing the rear takedown pin and sliding the barrel/action forward. The ejection chute can be wiped out with a cloth. Use a standard bore brush and solvent on the barrel. Reassemble in reverse order — no special tools needed.
Why Buy From Us
- ✅ Nationwide delivery to all 50 states (restrictions apply per local laws)
- ✅ Ships within 1-2 business days from our shop
- ✅ 30-day return policy on unused, unfired items
- ✅ Secure checkout with encrypted payment processing
Last updated: April 2026
Over 40% of bullpup buyers choose the RDB17 for its combination of light weight and affordability, according to industry sales data from 2025. We stock them in our shop and can answer any questions before you buy.
Browse more options in our Semi Auto Rifles category, or check out Bullpup Rifles and 5.56 Rifles for similar models.
Reviews
There are no reviews yet.