Barrel Length for Suppressed SBR 300 BLK

[merica_1776]

Hi Guys,

I'm starting to build an Upper chambered in 300 Blackout. I have the upper receiver group (Bravo Company) and BCG (AIM Surplus) already purchased.

I am wanting this to be a suppressed SBR build. The suppressor that I am going to use is a Dakota Silencer .308 Can (9.2") long. I have contacted the company and their requirements on a SBR is that the minimum barrel length be 9" for subsonic ammo and 12.5" for supersonic. My question is what is the best barrel length to pursue?

I currently have a .243 that is my main long range gun for Big Game and Varmints and I have a standard 16" 5.56 that I use as well. This gun will more than likely me used for night hunting coyotes and short range varmints (not sure if this setup would be good for deer). I will probably use the can on both my 243 and 5.56 form time to time, but mostly on the 300 Blackout.

I would like a shorter barrel since the can is 9", but I have read that the shorter the barrel, the more strain it puts on the can. Would it be worth going to a 10.5 or even a 12.5" barrel for that purpose? I will probably be shooting subs 95% of the time through it. I just don't want it to last as long as it can since it is a small fortune.

Thanks guys!

[merica_1776]

Hi Guys,

Also, one more question. What twist rate would be best for the recommended barrel length and info I provided earlier? 1:7 or 1:8.

Thanks

[BadKarmaZeroSix]

My opinion...1/7 twost on a 9" barrel works fine...my 6.5" barrel in 1/7 isnt MOA at 75yds, but im still working with a red dot and refining my loads...and troubleshooting some function issues...lol

[dvp18]

Is the suppressor selection set in stone or are you open to others? There are shorter options out there for the BLK that are just a quiet as larger cans.

Really 8-10" is a good length for a suppressed gun and it's really fine for supers as well. There is a little increase in muzzle velocity on the supers with increasing barrel length, something like 20-30 fps per inch in general. You have to decide what is the best setup for yourself based on how you plan to use the gun.

1:8 twist is fine for bullets up to 220 gr, beyond that you would be better off with a 1:7 to lessen the chance of the bullet destabilizing and causing a baffle strike. I personally prefer 1:7 on my guns.

[merica_1776]

No the suppressor selection isnt set in stone. I have just researched it and it seems like a really good can and I can get a decent deal on it

Do you have another brand/manufacture you prefer?

[rebel]

I like my AAC can. I like direct thread cans and have a Cyclone. No it's not uber light or anything but it sure hushes nice.

[dvp18]

That Dakota can seems pretty heavy at 20oz for a direct thread can, the SilencerCo Harvester would be pretty comparable I think, it is the same length and weighs in at 11.3oz, and it's only about $550 at various dealers. Not sure what kind of deal you can get on the Dakota can, but it retails for $850. Also there are quite a few QD cans out there that may work for you like the Specwars and the Sakers. I am also very interested in the new Dead Air suppressors, they look very promising and reasonably priced.

[merica_1776]

Those Dead Air suppressors look awesome! Whats the price on them? I couldn't find any info. Also, I was told that a threaded suppressor is more accurate than the QD, which is why I was looking at threaded only. Is that true? Or is QD's ok to use without sacrificing suppression or accuracy?

[dvp18]

Not necessarily, people tend to use them on precision guns because they are generally a little lighter than QD cans and the can is attached directly to the gun instead being attached to a muzzle device that is attached to the gun. Most people, myself included prefer QD cans on semi autos, it allows you to use one can on multiple rifles without having to install or remove anything from the gun to attach it. I have a Saker 762 that I can mount on any of my ARs (556, 300blk and 308) because they all have the same muzzle device.

This is the pricing I have seen for the Dead Air stuff, it's not confirmed info, but I have no reason to thinks it's wrong. Also these are MSRP prices, the street prices should be a somewhat lower. Red is my best guess at actual prices from dealers.

SANDMAN Ti - 762mm direct thread $849.00 MSRP $699-749

SANDMAN S - 762mm QD Silencer Muzzle Brake included $1,049.00 MSRP $849

SANDMAN L - 762mm QD Silencer Muzzle Brake included $1,199.00 MSRP $899

[jwb47]

if you are wanting to use your suppressor for multiple calibers then you will need one with Q.D. adapters . I have a yankee hill machine phantom with Q.D. adaptors and use it on 308 , 300 blackout and 5.56 . it is full auto rated and good for 300 magnum . they will warranty the suppressor down to 8.5 inch for 300 blackout . spend the extra money and get a quality light weight can you will appreciate it in the end . Im not saying my can is better or worse than any of the other manufactures , Im just saying think about your end use and go from there . from personal experience I say look for quality and light weight especially if you are going to hang it off the end of a 20-24 inch rifle or even a 16 inch . I wish I had went with a lighter weight but as usual they come out with the lighter version of mine after I already purchased the stainless steel version.