AR-15 Gas System For A 10.5" 300 Blackout Suppressed Build

[3MTA3]

I'm planning a 300 Blackout Build using a 10.5" barrel with a pistol length gas port. This will normally be shot with a suppressor. I would be shooting subsonic and supersonic ammo depending on what I was doing.

I'm trying to decide on a gas system and would like feedback from those who have used a similar configuration suppressed. I've had good experience with both DI and Piston on the AR platform and am not a fan boy of either. There are tradeoffs that for me pretty much cancel each other out.

The systems I'm looking at are:

1. Standard DI. My unknown here is if I need an adjustable gas block to adjust pressure when going between suppressed and nekkid. I also have no idea how much blowback I would get when suppressed and if it's enough to be distracting.
   
   
2. Adams 300 Blackout piston kit. It's designed for this application and comes with a lightweight bolt carrier by design. Adams sells a 10'5" 300 BO upper so it should be a workable option. I've done two builds using the Adams system and both have been flawless. Between the two piston systems I'm leaning this direction for that reason.
   
   
3. Superlative Arms pistol length piston kit. I've read where they say it's not compatible, but have watched several YouTube videos that were successful.

Have you used something similar to either of these in something similar to what I'm planning and how well did it work for you?

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[3MTA3]

Rephrasing the above and hoping to get some feedback. ID prefer to run DI unless a piston has a compelling reason. I plan to shoot it suppressed most of the time.

If you have used a short barreled 300 blackout DI system suppressed how clean did it run and was the blow back an issue? To you would the benefit of a piston outweigh the additional cost and propriety parts?

Did you need an adjustable gas block to move between suppressed and non suppressed?

Thanks in advance for your input.

 

[Lazyfaire]

Here is something to look at.
Has a switch on left side forward to switch from suppressed to non-suppressed.

W.A.R. - Innovative Arms Silencers

Like no other upper on Earth…The Killswitch® of the W.A.R. is built directly into the receiver. Leave it in between the two settings to shut “off” the gas.

innovativearms.com

 

[saxon]

Standard DI. My unknown here is if I need an adjustable gas block to adjust pressure when going between suppressed and nekkid. I also have no idea how much blowback I would get when suppressed and if it's enough to be distracting.

have this on a 10 and 7 and no issues going from suppressed to super with can on and or off, blowback is minimal on both, depending on powder if you reload.

 

[3MTA3]

have this on a 10 and 7 and no issues going from suppressed to super with can on and or off, blowback is minimal on both, depending on powder if you reload.

Thanks for that! What gas block and tube are you using? How dirty does it get compared to, say, a standard length 5.56?

I'll definitely be hand loading. Any powder suggestions to start with?

 

[saxon]

Thanks for that! What gas block and tube are you using? How dirty does it get compared to, say, a standard length 5.56?

I'll definitely be hand loading. Any powder suggestions to start with?

Aero Precision and about a dirty as any other,
H110, IMR 4227, Accurate 1680

 

[3MTA3]

Aero Precision and about a dirty as any other,
H110, IMR 4227, Accurate 1680

Thanks - I think I have my answer! Might have to play with buffers and perhaps low mass bolt carriers, but I have a direction.

Last Q - fixed or adjustable gas block?

 

[saxon]

300BlkTalk » Index page

fixed with .098 gas port

 

[Caveman Jim]

300BlkTalk » Index page

I used this site often for my 300BLK build (also a 10.5" barrel/pistol gas DI) and loading purposes.
I use W296 H-110 for supers from 125g HPFB to 155g HPBT bullets.
Good luck on your build.

 

[saxon]

I used this site often for my 300BLK build (also a 10.5" barrel/pistol gas DI) and loading purposes.
I use W296 H-110 for supers from 125g HPFB to 155g HPBT bullets.
Good luck on your build.

yup using that site i have 3 different 110 grain bullets that i load that give me one raged hole @ 36 yards