ADVANCED ARMAMENT CORPORATION’S HALCYON: TWO RIMFIRE SILENCERS IN ONE
Advanced Armament Corporation’s Halcyon: Two rimfire silencers in one
Whether you call them silencers, suppressors, mufflers or cans, we have always found the rimfire versions to be the most useful and practical. The latest one from AAC (Advanced Armament Corporation), the Halcyon, is one of the best of the breed.
A modular silencer, it has a removable front end that allows the user to run it long or short. This is patterned after the company’s modular pistol silencers in its Ti-rant M series.
When suppressing 17 HMR, 17 M2, 22 Mag- num or even FN’S 5.7, you may want to run a longer profile silencer for better suppres- sion, and in this case that is a matter of 5.28 inches with a weight of 6 ounces. However, if you want to quiet down a bolt-action 22 long rifle and keep a shorter profile you can
take it down to a 3.4-inch can that weighs a scant 4.5 ounces. Switching back and forth takes just seconds without tools just like the company’s Ti-rant 45M and Ti-rant 9M.
When our good friends at Silencershop.com asked us if we wanted to try it, we leaped at the chance and we had one ready to go in less than a week.
There is some good news on that front, courtesy of Silencershop.com. Owing to the staff’s background in IT (Information Technology), they recently teamed up with several industry partners and the NFA Branch to develop a bar-coded system for ATF Forms. It reduces some of the waiting period, particularly on the Form 3 (dealer to dealer) side as the forms need only be scanned. This saves 15 to 30 minutes on the part of an ATF Examiner who would need to type this information manually. Multiply that by the thousands of forms being processed and it adds up. Form 3 approvals have been reduced from 4-6 weeks down to 24 hours and sometimes less because of the bar code. We recently had one come back in less than an hour.
Unfortunately, Form 4 transfers are still taking close to a year for approval. This is a hazard of the NFA (National Firearms Act) and is mostly related to the implementation of 41P last July. However, we have seen more of the holdup on the side of the background checks taking longer than normal from the FBI/NICS desk.
With the wait times involved with NFA and the $200 tax stamp, we like to take advantage of modular cans, which give you in essence two silencers for one price. Not that you can make two standalone cans from one of these, but it gives you an option.
Taking the Halcyon apart, we noted that the baffles were K-type and made of titanium.
This keeps the weight down and reduces sound signature. Then we noticed that they were keyed for repeatable short alignment in an effort to not reduce but eliminate Point of Impact (POI) shift. The front section of the tube is made of aluminum and the rear portion is titanium with steel end caps. The whole unit is finished in armor-black Cerakote.
AAC promises additional adapters in other thread pitches to replace the standard ½ x
28” threaded end cap. Hopefully we will see ½ x 20” to use on European rimfire rifles and the threaded Beretta Model 71 pistols that were imported a few years ago by Century International Arms. Undoubtedly we will see end caps from AAC for use on various other rimfire handguns that have a two-piece barrel construction and can skip buying questionable adapters. We have heard a three-lug adapter is in the works, too.
Another unique feature that we have not seen elsewhere is a wave spring located under the rear end cap that applies tension to the thread adapter and aligns it to the main tube in order to prevent the rear cap from loosening while firing.
What really impressed us is the fact that the entire silencer can be taken down and reassembled, as well as reconfigured from long to short versions, without the use of tools. The baffles dump out of the tube easily and because they are titanium they can be cleaned more easily than stainless steel or aluminum baffles. You can use Hoppe’s #9 on these or clean them in an ultrasonic cleaner with no worries at all about degrading the material.
We took the Halcyon to the range with an assortment of rimfire rifles and handguns as well as our FN PS90 SBR (Short Barreled Rifle) and our full-auto Uzi with a 22 conversion kit, as the Halcyon is full auto-rated.
One of the design features that AAC set out to address specifically with the Halcyon was the elimination of first round pop (FRP). First Round Pop refers to the initial air trapped inside the suppressor. When this oxygen burns up after making contact with the hot gasses from the fired round it makes the first shot sound louder as a result of being fueled from the cooler air. Subsequent shots tend to be quieter. It is a problem with just about any type of sound suppressor but it does seem amplified in suppressed 22 rimfire cans. This is due to how inherently quiet most of these silencers are. The AAC Halcyon has minimalized this to such a degree that it is barely noticeable.
We mounted the short configuration on several rifles, including a Savage 93 and a S&W M&P 15/22. It was so quiet on the Savage that someone asked me if I was shooting a
pellet gun. The 16-inch barrel allows enough time and space for all of the powder to burn up before the bullet enters the silencer, and with no semi-automatic bolt or anything else to allow gas and noise to escape you can count on the full 43 db reduction promised by AAC.
That said, the S&W M&P 15/22 was only slightly louder. Plus, the look it gave this rifle made it appear to only have a slightly longer flash suppressor as opposed to a full-on sound suppressor. On the FN P90 (actually a PS-90 converted to an SBR) the longer version sounded better than the short mode. The short version may not have been completely hearing-safe, but it gave us no tinnitus from shooting it. Moving over to handguns, we found the longer version to work better with regard to sound reduction than the shortened one. This goes back to barrel length and burning time of the powder from the fired round.
The long version mounted on a Smith & Wesson model 41 was probably our quietest pistol host of the day. The Ruger Mk IV and Walther PPK/S in 22 LR worked well in each configuration, but our basic takeaway on the Halcyon is to run it short on rifles with 16-inch-plus barrels and long on anything shorter, including pistols.
An all-titanium rimfire suppressor would have been awesome, but would have undoubtedly driven up the price. As it is, an MSRP of $450
pushes it toward the higher end of the scale for 22 cans.
We were going to lay off on buying silencers until the Hearing Protection Act passed. However, in light of the current political landscape, we think we will see a Zamboni smoothing over the 9th circle of hell before that happens.
As the backlog from 41P is clearing at the NFA Branch and forms are starting to move more quickly through the system, along with consumer incentives in the form of lower prices and rebates, this is probably the best time in history to purchase a silencer.
The word Halcyon refers to a mythical bird, usually identified with the kingfisher, said to breed about the time of the winter solstice in a nest floating on the sea, and has the power of charming winds and waves into calmness. Alternatively, it can denote a period of time in the past that was idyllically happy and peaceful. In the spirit of either of those definitions, we think the Advanced Armament Corporation Halcyon is one of the best rimfire suppressors we have ever shot. It can make any day at the range, or a simple walk in the woods while out squirrel hunting, calm, happy and peaceful. Particularly with regard to the quiet time it gives.
We like to take advantage of modular cans, which give you in essence two silencers for one price.
The front section of the tube is made of aluminum and the rear portion is titanium with steel end caps. The whole unit is finished in armor-black Cerakote.
As the backlog from 41P is clearing at the NFA Branch and forms are starting to move more quickly through the system, this is probably the best time in history to purchase a silencer. A wave spring located under the rear end cap applies tension to the...
The Halcyon's baffles are K-type and made of titanium, keeping the weight down and reducing sound signature.
Full size is 5.28 inches with a weight of 6 ounces, but if you want to keep a shorter profile you can take it down to a 3.4-inch can that weighs a scant 4.5 ounces.
Our basic takeaway with the Halcyon is to run it short on rifles with 16-inch-plus barrels and long on anything shorter, including pistols.