Suppressor recommendations for B&T APC223 Gen 2 SBR

[1168]

Good question. My priorities for this can are:

1. Cost
2. Durability
3. Sound reduction

This makes it a little harder. You have an 8.75” barrel. And you also want to shoot .308. So, you’re looking for a 7.62 can with no barrel length restrictions. These may not work with your #1 priority, cost. And you’re married to Keymo, so you’re looking at a Sandman or something modular.

Priority #2 is easy, as long as you toss #1. If a can has a no BS warranty on an 8.75” 5.56, and 16” 308, it will probably meet your needs. *COUGH*Sandman S*COUGH* There are others, of course. Go to the Silencershop 7.62 page, sort by price, highest to lowest, and do some googling about the cans on the top page.

For #3, understand that a can that meets all your other requirements will not be optimized to meter well on a short 5.56, unless its pretty long, but that defeats the purpose of a SBR, IMO.

You might want to budget for two or three cans.

[1168]

These are good points.

Griffin Armament Recce 5

https://www.silencershop.com/griffin...t-recce-5.html

Cost is great
It’s made of 17-4PH which rivals Inconel 718 properties at a lower cost
It’s one of the quietest 5.56 cans tested by silencershop
And the taper mount is one of the best on the market when it come to repeatable poi shift when removing and reinstalling the can

OP, if you can overlook your 308 requirement, since you already have an Omega, take a look a a Griffin .224 can, like a Recce, M4SD, or Explorr. They sound great, but require a different mount. If you must use Keymo, check out Rex Silentium. They are pretty inexpensive. I have not gotten to hear mine, yet, though.

[VIP3R 237]

These are good points.



OP, if you can overlook your 308 requirement, since you already have an Omega, take a look a a Griffin .224 can, like a Recce, M4SD, or Explorr. They sound great, but require a different mount. If you must use Keymo, check out Rex Silentium. They are pretty inexpensive. I have not gotten to hear mine, yet, though.

Or get the Recce 7 which is a 30 cal can. Somehow I overlooked the .308 requirement

[MegademiC]

This makes it a little harder. You have an 8.75” barrel. And you also want to shoot .308. So, you’re looking for a 7.62 can with no barrel length restrictions. These may not work with your #1 priority, cost. And you’re married to Keymo, so you’re looking at a Sandman or something modular.

Priority #2 is easy, as long as you toss #1. If a can has a no BS warranty on an 8.75” 5.56, and 16” 308, it will probably meet your needs. *COUGH*Sandman S*COUGH* There are others, of course. Go to the Silencershop 7.62 page, sort by price, highest to lowest, and do some googling about the cans on the top page.

For #3, understand that a can that meets all your other requirements will not be optimized to meter well on a short 5.56, unless its pretty long, but that defeats the purpose of a SBR, IMO.

You might want to budget for two or three cans.

8.75” barrel + 8” silencer= 16.75”
11.5” barrel + 5” silencer = 16.5”

I have no idea what combo 1 sounds like. Especially in comparison to combo 2.
I also wonder if an 8” 223 was the right choice if sound suppression is a priority, and why did the op decide on that?

[hotrodder636]

I would go with the Sandman S. I have the L and love it but am thinking I want a shorter one for shorter setups. Built like a tank.

[Blackhalo]

YHM Resonator K or R2 if you want some extra baffles. End cap flash hider milled in and a decent price.

Both have modular mounts if you want to stick with keymo.

[1168]

Or get the Recce 7 which is a 30 cal can. Somehow I overlooked the .308 requirement

I have a buddy with a Recce 7, and its probably his most used centerfire rifle can. He loves it. Has at least a dozen other rifle cans.

YHM Resonator K or R2 if you want some extra baffles. End cap flash hider milled in and a decent price.

Both have modular mounts if you want to stick with keymo.

YHM would make sense, I think. Nevermind, see below.

[Mike Miller]

My first thought given his order of criteria would also be YHM, but the recommended min barrel length is 10.5" for 556 in the Resonator

[paco ramirez]

It sounds like your primary trouble is going to be finding a low cost silencer that realistically doesn't have minimum barrel length restrictions (as opposed to just marketing talk) for those cartridges that also sounds good. While it may be outside your price range, our Helios QD silencer comes as a full dual function kit that'll do everything you want it to do and more so it may be worth looking at. Alabama Arsenal and NFA Review will have videos posted on it in the next 1-5 days. I listed other options at the end.

The Helios QD is built as a hard use, and the first of its type dual function, 5.56mm silencer that just happens to have a 7.62mm bore. It doesn't have any barrel length restrictions, is full auto rated, and can be used on rounds up to 300 Norma Magnum/300 Remington Ultra Magnum and everything between including normal 7.62x51, 300 Blackout, 7.62x39, 6.8 SPC, 277 SIG Fury, etc. It can even be used on 338 Norma Mag/338 Lapua Mag but only if the barrel's bore, shoulder, and threads are all confirmed concentric. The larger bore also helps with unstable 5.56mm and similar bullets out of very short barrels, limiting the potential for baffle strikes. 718 Inconel is used as it outperforms every other material available at higher temperatures, especially when properly heat treated. The core's dual functionality allows the users to change the function of the silencer completely simply by swapping out the front cap for a different one. For example, the Standard Low Profile Front Cap that comes in the kit will allow the silencer to act as a really good traditional silencer, and the Vented Low Profile Front Cap that comes in the kit will allow the silencer to act as a "flow bypass" type silencer. It also doesn't suffer from particle erosion like traditional silencers all do. The Hyperion technology in the silencer core increases sound performance significantly, especially with supersonic ammo compared to everything else available, while not sacrificing subsonic performance to achieve supersonic performance. It excels at both without compromise. There is a whole lot more to write about the silencer system and kit, this is just a short overview.

The CGS Helios QD Kit comes with:
1) Helios QD Core
2) 1/2 x 28 TPI Direct Thread Mount
3) 5/8 x 24 TPI Direct Thread Mount
4) QD Adapter Mount for Omega Pattern 1.375 x 24 TPI QDs from various companies
5) Standard Low Profile Front Cap
6) Vented Low Profile Front Cap
7) Hook Wrench
8) Kit Case

Assuming .625" of barrel threads, the added length is only 6.58" in direct thread config including the hex on the front cap. Using a QD mount will add additional length depending on exactly what you want to use on it (any compatible 1.375x24 TPI mount). Dead Air KeyMo as an example will add more length than many because not only is the QD system long but the muzzle devices are long as well, adding an extra 2" from the bare muzzle.

Last week (5 MAR 2020) Maxim Defense did two SOCOM firing tables back to back on their PDX in 5.56mm with a 5.5" barrel and the CGS Helios QD installed, and the Helios QD didn't have any issues. They then did than same test with that same exact silencer on their 5.5" 7.62x39 with the same result, Helios QD didn't have any issues. It was even in its direct thread configuration with the closed off front cap, not the vented one, and it didn't back off the barrel, the direct thread shoulder joint to the silencer didn't come loose because it's on a shallow taper so it holds better than a 90 deg shoulder, and the front cap joint to the silencer didn't come loose either for the same reason.

SOCOM Firing Table (all mags fired immediately back to back, whole cycle repeated a second time after allowing Helios QD to cool to ambient):
Mag 1 - 1rd per Second - 30rds
Mag 2 - 2rds per Second - 30rds
Mag 3 - 1rd per Second - 30rds
Mag 4 - 3-5rd Bursts - 30rds
Mag 5 - 1rd per Second - 30rds
Mag 6 - 2rds per Second - 30rds
Mag 7 - 1rd per Second - 30rds
Mag 8 - Full Auto Mag Dump - 30rds
Total Rounds Fired per Test - 240rds

Since the test was done twice, that's 480rds through a 5.5" 5.56mm host in a very short amount of time. To put it into perspective how tortuous that test is, muzzle pressure of 5.56mm out of a 5.5" barrel is around 23,000 PSI compared to a 10” barrel which is 12,140 PSI or a 16” barrel which is 7430 PSI.

Here's what the silencer looked like after the 5.56 tests were completed: https://www.instagram.com/p/B9ZtgSgJJPA/

Also with a Larson Davis 800B meter (BK 2209 equivalent) the Helios QD (direct thread configuration and the standard closed off front cap) mounted on a 10" 7.62x39 Maxim Defense MDX metered 131.4dB average at the shooter left ear and on the 8" 7.62x39 MDX the Helios QD metered 133.1dB average at the shooter left ear which is pretty damn cool. Not sure why they didn't do the right ear other than brass probably hitting the mic. I think Phil Dater did the test, or at least was present for it.

They didn't tell us they were going to do that test either, I didn't know about it until after they'd already done it. I was overly happy with the way it turned out.

As far as other options maybe Rex Silentium would have something that fits the bill and maybe YHM can be talked to about the Resonator R2 minimum 5.56 rating but it's currently listed as 10.5" minimum. The Energetic Armament Vox S might do it as well, I don't think it has barrel length restrictions. Maybe the Inconel version SIG SRD762QD but then you can't use the KeyMo that you want to use. Just depends on how good you want your silencer to sound.

Griffin Armament Recce 5

https://www.silencershop.com/griffin...t-recce-5.html

Cost is great
It’s made of 17-4PH which rivals Inconel 718 properties at a lower cost
It’s one of the quietest 5.56 cans tested by silencershop
And the taper mount is one of the best on the market when it come to repeatable poi shift when removing and reinstalling the can

17-4 stainless doesn't rival 718 Inconel, it's not even close at high temperatures and neither is C300 maraging steel beyond 1000 deg F which is a material that also has big issues with corrosion. And Silencer Shops videos are completely useless as their meter cannot accurately measure gunshots and doesn't even come remotely close to meeting the minimum standards required to do so, which means 100% of the data that Silencer Shop has put out to date is 100% useless for any and all purposes beyond entertainment value. Silencer Shop recently picked up a BK Pulse meter (which can do the job very well and meets/exceeds current requirements) so assuming they're using the correct template, what Thunderbeast and Hansohn Bros/Suppressed Nation use, and assuming they're well trained on how to properly use the system then their future videos will actually be useful for data comparison instead of just for meaningless entertainment.

[MegademiC]

How do 17-4, inconel(whatever type is typical for baffles) stellite, and c300 stack up for high-temp erosion?

I have (probably erroneously) assumed the Ni-Co alloys were very close at the top, with 17-4 in 2nd place. Ive seen in marketed (17-4) as a balance of durability and price, which I read as not as good... but will likely last a lifetime on a semi with normal use.

Ti, im assuming is a distant 3rd (light use/hunting), and aluminum is unacceptable for rifles.

Looking for someone with experience/knowledge to confirm/correct.