YHM sRx QD Adapter and Mini Muzzle Brake Review

In December of 2022, Yankee Hill Machine (YHM) announced the release of their new sRx QD mounting system. This includes the following products:

sRx™ QD Adapter (YHM-4400)
sRx™ Short Flash Hiders (YHM-4445-24)
sRx™ Flash Hider (YHM-4405)
sRx™ Muzzle Brake (YHM-4405-MB)
sRx™ Short Muzzle Brake (YHM-4445-MB-24)
sRx™ Mini Muzzle Brake (YHM-4401-MB)

I recently picked up the sRx QD Adapter (mounted to my YHM Turbo K v2) and the sRx Mini Muzzle Brake, 1/2 x 28 (mounted the 16″ Faxon pencil barrel of my lightweight AR build).

sRx Mini Muzzle Brake Features

No need to time to barrel (no shims required)
Reduced size and weight compared to Phantom QD brakes
No moving parts
Taper seal to reliably lock suppressor on
Can be pinned and welded to barrel if desired

sRx Mini Muzzle Brake Specs

Length: 1.100″
Diameter: .9375″
Weight: 1.375 oz (according to my scale)
Made from: 4140 Steel
Finish: Black Phosphate
Available Sizes: 1/2 x 28 and 5/8 x 24

sRx Mini Muzzle Brake Pricing

MSRP is $82.95, but I bought mine for $55 from Lanbo’s Armory, when you add it to the cart. If you go to the Lambo’s Armory website, yes, it looks quite old, but it works fine and they are legit.

sRx QD Adapter Features

Low profile design and lightweight
Q.D. Adapter/Mounting Interface
Uses the industry standard (HUB) 1-3/8” x 24 threads
Internal taper seal to reliably lock suppressor in

sRx QD Adapter Specs

Length Added to Suppressor: .200″
Overall Length: .600″
Diameter: 1.563″
Weight: 1.875 oz (according to my scale)
Made from: 17-4 PH Stainless Steel
Finish: Black Oxide
Caliber(s): 9mm (.390 diameter) or smaller

sRx QD Adapter Pricing

MSRP is $82.95, but I bought mine for $55 from Lanbo’s Armory, when you add it to the cart.

YHM SRX Mini Muzzle Brake and QD Adapter — YHM sRx Mini Muzzle Brake and QD Adapter

General Impressions

The sRx QD Adapter

The sRx QD adapter is about the same size and weight as the YHM Kurz adapter (2 oz) made from steel. The titanium Kurz adapter is about .875 oz lighter than the sRx QD adapter.

However, an important difference is that the male threads of the sRx QD adapter that go into the suppressor, extend slightly further forward than on the Kurz adapter.

Why Might this Matter?

When I removed the Kurz from one of my YHM suppressors, there was some carbon build up covering the forward most female threads inside the suppressor, because the Kurz adapter threads did not extend far enough forward to conceal/cover the remaining female threads within the Turbo K. As a result, there was carbon buildup on those exposed threads.

This carbon buildup made it impossible to thread the sRx adapter completely into the suppressor (at least not without damaging the threads on the sRx adapter). Therefore, I would either have to remove the carbon or use a different YHM suppressor that does not have as much carbon build up on the end of those threads. Ultimately, I decided to use one of my other YHM suppressors (Turbo K) instead.

Carbon Buildup on Threads of a YHM Turbo T2

The sRx Mini Muzzle Brake

When I first opened the packaging of the sRx mini muzzle brake, I was really surprised by its extremely small size, even compared to my YHM Phantom mini brakes. At 1.375 oz, the sRx mini muzzle brake is also significantly lighter than the YHM Phantom mini brake, which weighs about 3.2 oz. The standard Phantom QD muzzle brake weighs even more, coming in at 3.875 oz. And, unlike the Phantom QD muzzle brakes, the sRx muzzle brakes do not need to be timed..no more shims!

Of course, the YHM sRx QD system is NOT compatible with the YHM Phantom QD system.

At the Range

According to YHM, you only need to hand tighten your suppressor (rotating it clockwise) when attaching it to your host using the sRx QD system.

After using YHM’s Phantom QD system over the years, I was a little worried that my Turbo K would walk off without the Phantom’s ratcheting mechanism. That said, after shooting about 220 rounds of 5.56 NATO, 55 gr FMJ, my YHM Turbo K with the sRx QD adapter, stayed on tight. The YHM sRx QD system makes attaching and removing my Turbo K suppressor very easy. That said, due to thermal expansion, you may need to wait until your suppressor cools down to ambient temperature before it can be removed. Otherwise, you might need to use a spanner wrench to break it free.

YHM Turbo K using the sRx QD adapter — The YHM Turbo K and sRx QD adapter is the shortest and lightest 5.56 Suppressor and QD system Yankee Hill Machine Offers

Final Thoughts

Is it worth getting the sRx QD Adapter and sRx Mini Muzzle Brake?

I think so. Even if you are already invested in the Phantom QD system, the sRx adapter and mini muzzle brake are not only much smaller, lighter and simpler (no springs, shims or moving parts), but less expensive as well.

I am really glad I bought the sRx QD adapter (1.875 oz) and sRx mini brake (1.375 oz). It definitely does save some weight off the front end of my rifle, especially compared to a standard Phantom QD adapter (2.75 oz) and a full size Phantom QD brake (3.875 oz) setup. The sRx QD system could end up saving you about 3.375 oz over the standard Phantom QD system.

YHM sRx QD system vs Kurz QD Adapter and Phantom Mini Muzzle Brake

Compared to the Kurz QD adapter and Phantom mini muzzle brake, the YHM sRx QD system reduces overall length an additional .3125 inches (by eliminating the need for a spring-loaded collar found on the Phantom muzzle devices). The sRx system also saves another .25 inches in length because it enables the muzzle brake to sit a little further forward inside the sRx adapter. The sRx mini muzzle brake also looks much better too.

Perhaps best of all, you may be able to buy the sRx QD adapter for just $55 and the sRx mini muzzle brake for $55, if you go to Lanbo’s Armory. Be sure to add these items to your cart to get the lowest pricing.