Suppressor options for .300 Blackout SBR

jasons

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I'm waiting for ATF approval on a Sig MCX Rattler in .300 Blackout with a 5.5" barrel. Any advice on a good suppressor? Priorities are reliability and good sound reduction above all else. Not super concerned with weight or length, within reason. I'll most likely be using whatever subsonic load functions best.
 
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I'm waiting for ATF approval on a Sig MCX Rattler in .300 Blackout with a 5.5" barrel. Any advice on a good suppressor? Priorities are reliability and good sound reduction above all else. Not super concerned with weight or length, within reason. I'll most likely be using whatever subsonic load functions best.
Do you want a well balanced silencer, does well on super and subs? The other option is to pick a silencer that will excel on subs but won't be great on supers. Most of these have a S (mid) and L (long) version, some even have a K version, if you want to trade length for suppression.

The best balanced 300BLK silencers I have are,
  1. CGS Hyperion (shorter) CGS Helios QD Ti
  2. Otter Creek Hydrogen L
  3. Diligent Defense Enticer L
  4. DAA Nomad L


The absolutely quietest on subs but falls off significantly on supers,
  1. Q Full Nelson
 
This is a great resource, still building the data sets but there is a decent amount of info on subsonic performance. You may have to re-sort.

 
A 5.5” barrel is going to be a whole lot louder and harder to suppress than a 9-10” or longer. So that in mind, I’d be leaning toward a longer suppressor and one that is easy to clean. You are going to be dealing with the effects of a lot more unburnt powder at that shorter barrel length. I think a longer and easy to clean suppressor is going to be a good idea.
 
Do you want a well balanced silencer, does well on super and subs? The other option is to pick a silencer that will excel on subs but won't be great on supers. Most of these have a S (mid) and L (long) version, some even have a K version, if you want to trade length for suppression.

The best balanced 300BLK silencers I have are,
  1. CGS Hyperion (shorter) CGS Helios QD Ti
  2. Otter Creek Hydrogen L
  3. Diligent Defense Enticer L
  4. DAA Nomad L


The absolutely quietest on subs but falls off significantly on supers,
  1. Q Full Nelson

Subs as long as they cycle reliably. I bought this thing to be quiet. I’ll look into the Full Nelson.
 
I've using Gordon's Reloading Tool to look at muzzle pressure predictions for different subsonic loads in 300AAC
With a 5.5" barrel it's going to be hard to get enough gas pressure to cycle and keep muzzle pressure low enough for efficient suppression.
On a 16" barrel with fast powders it showed muzzle pressures below 3kpsi - loud but well below the 12k+ pressures from the supersonic loadings.
At 5.5", you are probably going to have to hand load to get a clean burning round that reliably cycles while still staying subsonic.
 
I've using Gordon's Reloading Tool to look at muzzle pressure predictions for different subsonic loads in 300AAC
With a 5.5" barrel it's going to be hard to get enough gas pressure to cycle and keep muzzle pressure low enough for efficient suppression.
On a 16" barrel with fast powders it showed muzzle pressures below 3kpsi - loud but well below the 12k+ pressures from the supersonic loadings.
At 5.5", you are probably going to have to hand load to get a clean burning round that reliably cycles while still staying subsonic.

Seven inch one in five twist is pretty close to perfect.
 
At 5.5", you are probably going to have to hand load to get a clean burning round that reliably cycles while still staying subsonic

The MCX is known for being way overgassed, which is what does allow it to cycle factory subs with relative reliability. Especially when suppressed. But it is not the optimal rifle for those seeking to shoot quietly.

Handloading 300 aac, can get you a really quiet setup in a 16" barrel. Louder in the 8.5 - 10 or so range, but still pleasant. And downright loud even with a suppressor less than 8" in my experience. The MCX is a really cool rifle and has its use cases, don't get me wrong. But its not the setup if you are looking for quiet.

Best bet would be to find the heaviest bullet and the fastest burning powder that you can find verified load data for and try to get that to cycle.
 
I hate you free world people
[crying]

i sold my business and all my shit and moved into a hotel, then started looking for jobs and a place to live. you can do it too. it's like being anxious or depressed. it's easy and comfortable, but all you really have to do is decide to stop, and looking back you'll wonder why you hadn't done it sooner.
 
i sold my business and all my shit and moved into a hotel, then started looking for jobs and a place to live. you can do it too. it's like being anxious or depressed. it's easy and comfortable, but all you really have to do is decide to stop, and looking back you'll wonder why you hadn't done it sooner.
Working on it
Might end up costing my half of everything but I'd be happy with a single wide on a secluded lot.
 
Working on it
Might end up costing my half of everything but I'd be happy with a single wide on a secluded lot.

I knew I'd have less space and gave away everything I couldn't sell. It was actually really cathartic, now I have minimal possessions and the house is easier to clean. Basically gave away everything that I couldn't sell and was a pita to pack. It's amazing how much clutter I had and how little I actually need.Moving truck quoted me based on 24' of space on the truck and I made it work. Hardest was selling the motorcycles. Had to keep all my books though. Life is all about sacrifice. If you feel like coming to bluegrass shoot me a PM and I'll help you out however I can.
 
Following along. Just picked up a Sig MCX TACOPS. Plan to build it into a SBR and add a suppressor.
 
they new Sig can the SLS is made to be the best with subs, the SLX works better with super sonic ammo. they both will push the gasses forward and test better then no can at all
 
they new Sig can the SLS is made to be the best with subs, the SLX works better with super sonic ammo. they both will push the gasses forward and test better then no can at all

I’ve been looking into that one. Still waiting on the SBR to clear paperwork so I haven’t “pulled the trigger” on a can yet, but I like the idea of keeping it all Sig so if it doesn’t work well I can bring the whole mess to Epping.
 
I had the surefire 7.62 mini on my 300 blk mcx sbr with a 9” barrel. Ran and cycled fine but It was louder than I expected and the QD muzzle devices were about $150 each (none came with the can).
 
This is a great resource, still building the data sets but there is a decent amount of info on subsonic performance. You may have to re-sort.


Holy sh*t...that's a lot of data! Awesome.
 
I'm waiting for ATF approval on a Sig MCX Rattler in .300 Blackout with a 5.5" barrel. Any advice on a good suppressor? Priorities are reliability and good sound reduction above all else. Not super concerned with weight or length, within reason. I'll most likely be using whatever subsonic load functions best.
Isn't the Rattler considered a pistol, and no stamp needed?
 
Isn't the Rattler considered a pistol, and no stamp needed?
I think they do (or did?) make a pistol brace version but the one I ordered has a foldable stock.
 
they new Sig can the SLS is made to be the best with subs, the SLX works better with super sonic ammo. they both will push the gasses forward and test better then no can at all
Did you mean SLH versus SLS?
I have a SLH QD in jail and I’m looking forward to it’s escape but at 1400 a copy it was the more expensive can in the display case.
I do need to acquire a couple of QD’s
 
they new Sig can the SLS is made to be the best with subs, the SLX works better with super sonic ammo. they both will push the gasses forward and test better then no can at all
I'm calling bullshit until I see a flow restriction test that proves otherwise. Sig wants me to believe that adding a silencer to a rifle will increase flow over an unsuppressed weapon, nah.
 
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