Diamondback DBX57 5.7×28 8in Braced Pistol, 20rd
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Specs at a glance
About this product
We just got in a batch of the Diamondback DBX57 5.7x28 8in braced pistol, 20rd, and folks, this is a compact powerhouse that shoots flat and handles quick. It runs the fast, low-recoil 5.7x28 round in a locked-breech, dual gas piston system—built on 7075 T-6 aluminum receivers with a hard coat anodized finish. You get an 8-inch threaded barrel, a 6061 aluminum M-LOK handguard, a Magpul MOE-K grip, and an SB Tactical FS1913 side-folding brace right out of the box. One 20-round magazine that fits FN Five-seveN mags is included.
Specifications
| Manufacturer | Diamondback Firearms |
|---|---|
| Model | DBX57 |
| Material | 7075 T-6 aluminum receivers (per manufacturer specs) |
| Compatibility | FN Five-seveN 20-round magazines |
| Finish | Hard coat anodized |
| Weight | 4.5 lbs (with brace and empty magazine, per manufacturer specs) |
| Condition | New |
Key Features
- Locked-breech dual gas piston system — Why it matters: This keeps the action running clean and cool, even with the hot 5.7x28 round, and cuts felt recoil way down for fast follow-up shots.
- 8-inch threaded barrel with DBX muzzle device — Why it matters: You can run a suppressor or compensator easily, and the included muzzle brake tames muzzle rise so you stay on target during strings.
- SB Tactical FS1913 side-folding brace — Why it matters: Folds to the left for a compact carry size, yet locks up solid when deployed so you get a stable shooting platform every time.
- 6061 aluminum M-LOK handguard — Why it matters: Lets you mount lights, lasers, or a foregrip exactly where you want them without extra adapters or added weight.
- Magpul MOE-K grip — Why it matters: That steep angle and textured surface give you a natural, repeatable hold—especially helpful for shooters with smaller hands or when wearing gloves.
Who It's For
The DBX57 is for anyone who wants a lightweight, braced pistol that packs the speed and low recoil of 5.7x28. It fits the new gun owner looking for an easy-shooting home defense tool, the family who wants something their spouse or older kids can handle comfortably, and the local shooter who likes to run drills without beating up their shoulder. The folding brace also makes it a great truck gun or pack gun for folks who spend time outdoors.
Pros & Cons
- Pro: Runs on common FN Five-seveN magazines—spares are easy to find and affordable.
- Pro: The 8-inch barrel wrings extra velocity out of 5.7x28, giving you better terminal performance than shorter pistol barrels.
- Pro: Ambidextrous safety and bolt release make it lefty-friendly right out of the box.
- Con: The trigger is serviceable but not match-grade—it has a bit of take-up and a 6.5-pound pull. If you're used to a crisp aftermarket trigger, you'll notice it. That said, it breaks clean enough for defensive use.
Comparison
| Feature | Diamondback DBX57 | Ruger LC Carbine (5.7x28) | PSA Rock 5.7 (5.7x28) |
|---|---|---|---|
| Barrel length | 8 inches | 16.1 inches | 4.8 inches |
| Operating system | Dual gas piston | Blowback | Blowback |
| Brace/stock | SB Tactical FS1913 (folding) | Fixed stock | Adjustable brace |
| Weight | 4.5 lbs | 6.4 lbs | 1.7 lbs |
| Magazine compatibility | FN Five-seveN | Ruger proprietary | PSA proprietary |
| MSRP | $1,091.29 | $999.00 | $599.99 |
FAQ
What magazines does the Diamondback DBX57 use?
The DBX57 ships with one 20-round magazine that is compatible with FN Five-seveN 20-round magazines. You can use standard FN factory mags or aftermarket options like ProMag or Mec-Gar that fit the FN pattern.
Can I mount a suppressor on the DBX57?
Yes. The barrel is threaded 1/2x28 with a standard thread pitch, and the included DBX muzzle device can be removed. Just make sure your suppressor is rated for 5.7x28 pressures. The dual gas piston system also keeps gas blowback low, which is a plus with a suppressor.
Is the brace adjustable for length of pull?
The SB Tactical FS1913 brace has multiple adjustment positions on the folding mechanism, so you can set the length of pull to fit your frame. It also folds to the left for compact storage.
What is the warranty on the Diamondback DBX57?
Diamondback Firearms backs the DBX57 with a limited lifetime warranty to the original owner against defects in materials and workmanship. If something breaks due to a manufacturing issue, they'll fix or replace it.
Why Buy From Us
- ✅ Nationwide delivery to all 50 states
- ✅ Ships within 1-2 business days
- ✅ 30-day return policy
- ✅ Secure checkout
Last updated: April 2026
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