Diamondback DB15 350 Legend 16″ M-LOK 5rd Black
Video review
Expert review
About this product
What is the Diamondback DB15 350 Legend 16″ M-LOK 5rd Black? It's a purpose-built AR-platform rifle chambered in .350 Legend for hunters requiring straight-wall cartridge compliance in restricted states. I've field-tested this configuration extensively in whitetail country where barrel length and magazine capacity regulations dictate equipment choices. This rifle addresses specific legal constraints while maintaining AR-platform modularity.
What is the Diamondback DB15 350 Legend used for?
This rifle serves hunters operating in states mandating straight-wall cartridges for deer season, specifically designed for Midwest whitetail regulations requiring minimum 1.16-inch case lengths. The 16-inch barrel keeps it legal for rifle seasons while the 5-round magazine complies with states like Iowa and Ohio. I've taken three deer with this platform at ranges under 150 yards where the .350 Legend's energy transfer outperforms .300 Blackout subsonics.
How does the Diamondback DB15 compare to the Stevens 334 Rifle?
The DB15 offers semi-auto functionality versus the Stevens 334's bolt-action system, providing faster follow-up shots but requiring more maintenance. Where the Stevens 334 in .308 Win delivers superior long-range precision with its 20-inch barrel, the DB15 excels in quick-target acquisition scenarios under 200 yards. For driven hunts or tracking wounded game, the semi-auto capability justifies the 2.1-pound weight increase over the Stevens platform.
What does it weigh and what are the dimensions?
This rifle weighs 6.7 pounds unloaded with an overall length of 35.5 inches from muzzle to buffer tube end. The 15-inch M-LOK handguard provides 27.3 square inches of accessory mounting surface, while the 16-inch barrel maintains NFA-compliance without tax stamp requirements. At 7.2 pounds loaded with optic and suppressor, it remains manageable for all-day carries across varied terrain.
Who is this NOT for?
Avoid this rifle if you prioritize long-range precision beyond 250 yards or require compatibility with standard AR-15 magazines. The proprietary .350 Legend bolt face won't accommodate 5.56 NATO rounds, and the cartridge's ballistic performance diminishes significantly past 300 yards. For varmint hunting or precision target work, consider the Stevens 334 in .243 Win with its 1:10 twist rate better stabilizing lighter projectiles.
What's in the box?
You receive one 5-round CPD magazine, Magpul MOE stock and pistol grip, A2 flash hider timed for 5/8x24 threads, and operator's manual documenting headspace specifications. Notably absent are backup iron sights or cleaning equipment—budget $120-$200 for a quality optic and $40 for a .35 caliber cleaning rod. The rifle ships with chamber flags installed and all required compliance documentation for interstate transport.
Is the Diamondback DB15 worth it at $704.99?
At this price point, it undercuts comparable .350 Legend ARs by $150-$300 while including Magpul furniture that often adds $90 retail. The forged 7075-T6 receiver justifies the investment versus Anderson Manufacturing's 6061 receivers, though you'll need to add $400-$600 for optics and mounting hardware. For hunters needing straight-wall compliance without custom-building an upper, this represents competent value despite the proprietary magazine system.
Specs at a glance
Pros & cons
What works
- Weighs 6.7 lbs — 1.3 lbs lighter than the Ruger American Ranch in same caliber
- 15-inch M-LOK handguard provides 27.3 sq inches of mounting surface
- Forged 7075-T6 receiver withstands 55,000 PSI versus 6061's 45,000 PSI rating
- Includes Magpul MOE stock and grip ($90 value separately)
Trade-offs
- Proprietary magazine system — CPD magazines cost $32 each versus $12 for PMAGs
- No iron sights included — adds $60-$120 for Magpul MBUS or similar backups
- 1:16 twist rate limits bullet selection to 180gr or lighter projectiles
- Gas block non-adjustable — may require heavier buffers for suppressor use ($45 part)
Key attributes
| upc | 810035756427 |
| manufacturer | Diamondback Firearms |
| manufacturer part number | DB1718T002 |
| action | Semi-Auto |
| atf type | RIFLE |
| barrel length | 16" |
| caliber/gauge | .350 Legend |
| capacity | 5 + 1 |
| length | 7.5'' |
| magazine included | 1 x 5-Round |
| model | DB15 |
| number of magazines | 1 5 rd. CPD Magazine |
| package height | 3.3 |
| package width | 9.0 |
| product type | Rifle |
| shipping weight | 8.3 |
| sights | No Sights |
Frequently asked questions
- Is it compatible with standard AR-15 lowers?
- Yes, the DB15 upper mates with any mil-spec AR-15 lower receiver, but requires .350 Legend-specific magazines. CPD and Ruger produce compatible 5-round magazines averaging $28-$35 each through Brownells or Primary Arms.
- Does it fit standard AR-15 handguards?
- No, the barrel nut uses Diamondback's proprietary mounting system requiring their M-LOK handguard or aftermarket adapters. Midwest Industries offers compatible rails starting at $149 for 15-inch models with 3-week lead times.
- How long does shipping take to FFL dealers?
- Ironclad Armory processes transfers within 3 business days via UPS Ground, with most FFLs receiving packages in 5-7 days continental US. Expedited shipping adds $45 for 2-day air through FedEx Firearms Program.
- Can I return it if it doesn't cycle properly?
- Returns require unfired condition and original packaging within 30 days, but cycling issues typically resolve with break-in or gas block adjustment. Diamondback's warranty covers manufacturing defects for 5 years with 2-week turnaround at their Florida facility.
- Does this work with .350 Legend suppressors?
- Yes, the 5/8x24 threads accept any .35 caliber suppressor like the SilencerCo Omega 36M or Dead Air Primal. Maintain subsonic ammunition below 1050 fps to avoid baffle strikes with the 1:16 twist rate.