DANIEL DEFENSE ISR (MIL SPEC)

Product Description

The DANIEL DEFENSE ISR (MIL SPEC) is a purpose-built .300 AAC Blackout rifle engineered for suppressed shooting right out of the box. Its fully integral stainless steel suppressor is pinned and welded to a 9″ fluted Cold Hammer Forged barrel, bringing total barrel length to 16″ for legal rifle classification. No separate suppressor to attach, align, or zero—just uncase it and run it suppressed.

Furthermore, this rifle pairs a pistol-length gas system with a 1:8 twist rate optimized for both subsonic and supersonic .300 AAC Blackout ammunition. The result is greatly reduced muzzle blast and flash without sacrificing reliability or accuracy. Every DANIEL DEFENSE ISR ships hand-assembled, quality-assured, and test-fired to verify performance before it leaves the factory.

Additionally, the Daniel Defense MFR XL 15.0 free-float KeyMod handguard delivers a continuous top Picatinny rail and generous mounting real estate for lights, lasers, and vertical foregrips. This rail system keeps your setup modular and lets you tailor the rifle to your mission.

Built for Suppressed Precision

The integral suppressor design eliminates the variables that separate suppressors introduce. You get consistent, predictable performance from day one. The 1:8 twist stabilizes both heavy and standard .300 AAC Blackout loads reliably.

Materials & Construction

• Lower Receiver: Daniel Defense Mil-Spec Lower Receiver with Enhanced Flared Magazine Well and Rear Receiver QD Sling Swivel Attachment Point, CNC Machined of 7075-T6 Aluminum, Type III Hard Coat Anodized
• Upper Receiver: Mil-Spec Upper Receiver with Indexing Marks and M4 Feed Ramps, CNC Machined of 7075-T6 Aluminum, Type III Hard Coat Anodized
• Barrel: 9″ S2W Profile (Daniel Defense’s Proprietary Heavy Barrel), Fluted with Target Crown, Chrome Moly Vanadium Steel, Cold Hammer Forged, 1:8 Twist, Chrome Lined, Mil-Spec Heavy Phosphate Coated
• Integral Suppressor: All Stainless Steel Construction, 17-4 PH Monolithic Baffle Stack, High-Temp Cerakote-C Coated Outer Tube, Pinned and Welded Permanently to the Barrel, User-Serviceable Baffle Core for Cleaning — Extends Overall Barrel Length to the NFA-Required 16″
• Gas System: Daniel Defense ISR Integrated Gas Block, Pistol-Length, Direct Impingement
• Handguard: Daniel Defense MFR XL 15.0, Free-Float, KeyMod Attachment Points at 3/6/9 O’Clock with Continuous Top 1913 Picatinny Rail, CNC Machined of 6061-T6 Aluminum, Type III Hard Coat Anodized
• Bolt Carrier Group: M16 Profile Bolt Carrier Group, Mil-Spec MP Tested, with Properly Staked Gas Key
• Charging Handle: Daniel Defense GRIP-N-RIP Charging Handle — Independently Ambidextrous, Body CNC Machined of 7075-T6 Aluminum, Handles & Latch CNC Machined of 6061-T6 Aluminum, Heavy Duty Stainless Steel Roll Pins, Type III Hard Coat Anodized
• Buffer: Mil-Spec H Buffer
• Receiver Extension: 6-Position Mil-Spec Carbine Receiver Extension, 7075-T6 Aluminum
• Buttstock: Daniel Defense Buttstock, Glass-Filled Polymer with Soft-Touch Overmolding, Non-Slip Cheek Weld, Interchangeable Butt Pads, and Integral QD Sling Swivel Attachment Point
• Pistol Grip: Daniel Defense Pistol Grip, Glass-Filled Polymer with Soft-Touch Overmolding and Ergonomic Wrist Angle
• Vertical Grip: Daniel Defense Vertical Grip, Glass-Filled Polymer with Soft-Touch Overmolding

Specifications

This rifle’s suppressor is permanently pinned and welded to its barrel, extending the overall barrel length to the NFA-required 16 inches — so the rifle itself is NOT classified as a Short-Barreled Rifle and needs no SBR paperwork. The integral suppressor itself, however, IS a Title II item regulated under the National Firearms Act (NFA). Before taking possession, the buyer (or their trust/entity) must have an approved ATF Form 4 transfer application on file and a completed NFA background check. As of January 1, 2026, the federal transfer tax for this is $0 under the One Big Beautiful Bill Act, but the ATF paperwork and approval process is still required. Approval times vary, though ATF’s eForms system has shortened typical individual processing to roughly 1-3 months in 2025-2026 (historically much longer for paper filings). The rifle must be transferred through Western Sport’s SOT/Class 3 process to a licensed dealer in the buyer’s state, and some states restrict or prohibit civilian suppressor ownership outright. Western Sport cannot advise on individual compliance — buyers are responsible for following all applicable federal, state, and local law.

Why Buy from Western Sport?

• Western Sport’s expert staff know Daniel Defense rifles inside and out and answer your questions honestly.
• We price competitively on all Daniel Defense rifles, including this hard-to-find ISR configuration.
• Personal service means you get support before, during, and after your purchase.
• Fast shipping and hassle-free returns back up every rifle we sell.
• As a trusted local retailer, we stand behind the quality and reliability of every Daniel Defense product.

Frequently Asked Questions

Q: Which .300 AAC Blackout ammunition works best in this rifle?

A: The 1:8 twist rate and pistol-length gas system handle both subsonic and supersonic loads reliably. Subsonic rounds (like 220–240 grain projectiles) deliver quiet, suppressed performance ideal for hunting. Supersonic rounds (125–147 grain) offer flatter trajectory and higher velocity when sound signature matters less.

Q: What optics and accessories work with the KeyMod handguard?

A: The continuous top Picatinny rail accepts any standard-mount optic—red dots, magnified scopes, and hybrid sights all fit. The KeyMod slots on the sides mount lights, lasers, bipods, and vertical grips securely. Standard AR magazines and slings attach without modification.

Q: What makes the integral suppressor design better than attaching one separately?

A: An integral suppressor pinned and welded to the barrel eliminates alignment drift and re-zeroing hassles. You get consistent accuracy from first shot to last. The design also balances the rifle naturally, reducing felt recoil and improving control in rapid fire.

Q: What comes in the box, and does this rifle ship ready to shoot?

A: The ISR (MIL SPEC) ships fully assembled, hand-tested, and ready to fire suppressed out of the case. You’ll receive the rifle, a magazine, and documentation. No separate suppressor or special tools required—just add your preferred optic and ammunition.

Q: What is the KeyMod handguard on this rifle?

A: KeyMod is a slim attachment system that lets you mount lights, lasers, and foregrips directly onto the handguard without separate rail sections. Additionally, the Daniel Defense MFR XL 15.0 handguard floats independently of the barrel, so attachments don’t shift your zero. A continuous top Picatinny rail still provides a stable mounting surface for optics and iron sights.

Q: Do I need to file ATF paperwork or pay a tax stamp for this rifle?

A: Yes, but only for the integral suppressor — not the rifle itself. Because the suppressor is permanently welded to the barrel, the overall barrel length meets the 16-inch minimum, so this is not a Short-Barreled Rifle. However, the suppressor is a Title II item under the NFA. You’ll need an approved ATF Form 4 and a completed background check before taking possession. As of January 1, 2026, the federal transfer tax for this is $0 under the One Big Beautiful Bill Act, but the ATF paperwork and approval process is still required.

Also in the ISR Family

DD M4 ISR 300BLK 16″ 32RD BRN  •  DD M4 ISR 300BLK 16″ 32RD BLK  •  Daniel Defense DDM4 ISR Upper Receiver Group  •  DANIEL DEFENSE ISR (Deep Woods Cerakote)  •  Daniel Defense M4 Carbine, ISR-300 Blackout

Additional information