Maxim Defense SDX RFLX SBR .300 Blackout
Model: MXM-49219
Maxim Defense SDX RFLX SBR .300 Blackout
Model: MXM-49219
Full Specifications
About This Firearm
The Maxim Defense SDX RFLX SBR is an integrally suppressed .300 Blackout short-barreled rifle built for suppressed hunting and suppressed range work. It has an MSRP of $3,695. Its RFLX suppressor wraps back over the 8.5 inch barrel, which is how a rifle carrying a full-size can still measures 33 inches extended and 8.2 lbs.
A full-length Picatinny rail runs the top of the upper, so an optic and a night vision clip-on can both sit where the mount wants them, and the trigger is an ALG unit. The Gen:7 CQB stock brings the rifle down to 28.75 inches collapsed. Maxim describes the can as removable with no barrel length restriction behind it, so it can come off for service.
If you're cross-shopping, the Maxim Defense PDX:SD SBR carries the same MSRP of $3,695 with a 5.5 inch barrel, 23.75 inches of length and 7.4 lbs, so it is the compact end of the same idea. The Daniel Defense DDM4 ISR has an MSRP of $3,945, a 9 inch barrel and 7.6 lbs at 34.75 inches, but its suppressor is pinned and welded on, where the RFLX unscrews.
Best For
Strengths & Limitations
- The muzzle is threaded 5/8x24, the usual .300 Blackout pitch, so the can mounts on a standard interface and not a proprietary one.
- It is built on Maxim's SDX 508 platform, so the host under the suppressor is a production gun and not a one-off.
- Arid and black are both catalog colors, and a matching pistol configuration sells at the same price.
- 8.2 lbs is before an optic, a light or a loaded magazine, so a sling is part of the setup, not an accessory.
- These are built to order on a four to six week lead time.
- Maxim lists .300 Blackout as the single chambering, so there is no 5.56 build of this rifle to share parts with.
Compatible Ammunition
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Frequently Asked Questions
What does the Magpul CTR stock option change?
Maxim also builds the SBR with a Magpul CTR stock in place of the Gen:7 unit. That version lists 34 inches extended and 7.8 lbs, so it is a little longer and a little lighter than the Gen:7 build.
How does the SBR differ from the pistol version?
Maxim sells both at the same price, with the same barrel and the same integrated suppressor. The stock changes and little else, so the pistol is the same system with a brace where the Gen:7 unit goes.
What is M-Kore?
M-Kore is Maxim's own suppressor core technology, used in the integrated RFLX can here and in the Maxim Defense PDX:SD SBR. Maxim tunes the can and the gas system together, which is why the suppressor is sold as part of the firearm and not as an accessory.
