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Mus Moderator

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Congratulations, you've found our secret menu. Here you can find products which don't fit in, are oddball, we can't produce in large volume, don't have the level of polish we expect from our standard line of products, are experimental, are pet projects, etc. Keep an eye on this space as we don't advertise it, and you never know what you'll find here, but don't forget this page exists for you: our loyal fans and customers. 

Mus Moderator

Mus final rev. DD pic.png
Mus final rev. DD pic.png

Mus Moderator

from 163.00

Mus is latin for mouse, a reference both to the size and sound of this moderator. At only 170x50mm this design is obviously anything but small, yet weighs a scant 120 grams, which is vastly lighter than anything else in its size class. An optional stainless steel thread insert adds an additional 3 grams. The core is manufactured from an ultra light weight, strong, and solvent resistant 20% high modulus carbon fiber reinforced nylon. (nylon alone is what Glock frames are made out of) It attaches via a 1/2-20UNF thread.

Contrary to conventional wisdom, simply making a moderator design larger in diameter does NOT make it quieter. Our testing has show the opposite phenomenon occurring to a shocking extent, where a larger tube diameter can make it considerably harder to mute the initial sound peak or “uncorking” sound of an airgun. The precise mechanism behind this phenomenon is unclear, and it likely has not come to light up until this point for two reasons: First there is a strong expectation, and the subjective ear can sincerely taint observation. The second is that the overwhelming majority of sound meters are not capable of capturing this peak measurement, which would in turn feed into the (false) expectation that larger is better. Irrespective of its mechanism, this phenomenon was clearly demonstrated in the common felt/flat baffle designs used in most commercial moderators including Hugget, 0dB, DonnyFL, and Clague. It transcends this design architecture however, you’ll notice we had many puzzling failures, making the design and construction of high performing large diameter moderators remarkably challenging. This has been something we struggled greatly with, and had more failed prototypes than any other moderator project BY FAR.

Time and perseverance have allowed us to crack this problem though, and the result is a large diameter designs which out-performs its skinny brethren of equal length on moderate flow guns, while weighing as little as other company’s much much smaller designs. There is a catch though, and that is the initial peak is not dramatically better than what would be found on the comparable moderate flow Pilum. What has been significantly improved is the post-uncorking sound attenuating properties. Put more simply, the sound of the moderator emptying its pressure after than initial “uncorking” sound has been made much quieter, which makes for a design that is quite pleasing to the ear. Subjectively, particularly to the untrained ear which is unable to differentiate between peak and sustained sound, it is a substantial improvement over the Pilum particularly under moderate flow conditions.

Given all that expounding on how challenging the development was, how then does it work? In short it is a combination of our proven gas diode and sound damping technologies found in the Pilum and Levitas combined with a concentric chamber design. First a compound blast deflector strips turbulence off the pellet to improve accuracy and move air to a separate chamber which is able to act as a pressure reservoir, taking advantage of the can’s much larger volume than the Pilum (approximately twice as large). This then slowly (relatively speaking) feeds the gas diodes which delay that pressure wave. Finally, the sound generated is mopped up by our proven sound damping architecture. Many different subtle revisions and tweaks were necessary to reach this peak performance. It should also be noted that this design, while optimized for moderate flow, is not a horrible performer on standard flow guns. Peaking around 80 and being pretty tranquil subsequent, this design could be thought of as our most well-rounded offering.

This product is intended for AIRGUN USE ONLY! It is a violation of federal law to use this product in a manner inconsistent with its design intent. More information about the federal court ruling which clarified the legality of airgun moderators within the United States can be found HERE. Local restrictions may still apply. It is the responsibility of the buyer to ensure they are in compliance with all applicable laws. United States Orders Only!

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It would be absurd to think one moderator design would produce optimized sound attenuation for all levels of air flow. Based on our test platforms, we’re optimizing for two different clearly stated power/flow situations. We recommend you select the moderator which most closely matches your own application in order to maximize effective sound attenuation. To be clear, ALL OF OUR DESIGNS WORK ON ALL OF THESE TEST INSTANCES, but the optimized ones will produce better sound attenuation. All our moderator bores are 8.4mm. Larger diameter bores are available upon request.

Standard - Optimized on a shrouded FX Crown .22 producing 32 foot pounds. In factory configuration with extended shroud, average peak is _____

Moderate - Optimized on a shrouded FX Crown .30 producing 80 foot pounds. In factory configuration with extended shroud, average peak is 78.8

Mus moderate on .22.png

Mus trace (moderate flow) as tested on a shrouded FX Crown .22. At current there is no standard flow Mus variant which out-performs the Pilum, so we simply don’t offer it. It is worth noting though that, while the peak is higher than the standard flow Pilum, there appears to be a slight advantage in sound signature reduction after the peak. Average peak was 82.0.

Mus trace (moderate flow) as tested on a shrouded FX Crown .30 showing the peak, and more effectively attenuated post-peak sound than the comparable PilumQD. Average peak was 78.8.

Mus final rev. DD.png