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Help with 300BLK barrel choice

Outlaw45

Sergeant
Full Member
Minuteman
Nov 12, 2007
600
25
46
Iowa, USA
I'm looking to get a 300BLK barrel for my AR. I want to stay with a 16" barrel cause I'm in Iowa and we don't get fun toys yet. We don't have suppressors either but hopefully soon. So my question is what gas system should I get pistol or carbine? It will have to run without a suppressor for now. Can I run subs and supers unsuppressed? Then also run subs with suppressor?

I see a lot of barrels made with carbine gas systems and only a couple with pistol gas systems, Rainier ultramatch and Noveske.
 
If you're sticking to a 16" length, you should be fine with either gas system length. AAC appears to run a carbine length gas system on their 16" and I believe that they advertise being able to run supers and subs unsuppressed. Speaking of the AAC barrel, they are having a sale on that barrel right now (25% off) and the gas tube and gas block are included. Another option to consider...
 
I did a lot of reading on this exact topic in the very near past and the general consensus seemed to be that the pistol length was the way to go..

it will still maintain enough chamber pressure to cycle the subsonic rounds even without the can more reliably than the carbine length..

on the other end of the spectrum it seems that the only ill consequence of the pistol length with the can on while shooting sonic rounds would be that you would be rougher on the brass..

but again this is all from the reading I did mostly from the other members of this site not personal experience
 
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John Noveske spent a lot of time and money investigating the .300 BLK. He felt like the pistol length gas system and the 1x7" twist was the single best way to go regardless of barrel length.

^ good point! the entire industry actually seems to have gone to the 1 in 7 only a few still cling to the 1 in 8 and you hardly see anything left in the slower twist rates 9 10
 
I ordered a Model 1 sales upper.
I spoke to one of the builders there, he told me that with a 16" barrel running the carbine porting would not reliably cycle the subs unsuppressed.
I recently received the upper. Fit and finish is very nice, I haven't had an opportunity to shoot it yet.
 
I read on m4carbine.net that the consensus is pistol length too. I guess for the time being I don't have a suppressor and with them not legal at the present time, there's no use shooting subsonic rounds. Would shooting supers be to much gas with a pistol gas system? And then if shooting supers with pistol gas system and with a suppressor?
 
there is alot of B.S. out there about carbines and running subs un-suppressed . with a 16 inch barrel you need to run a regular carbine buffer and spring . when handloading use 1680 powder for heavy sub-sonic loads and you should be alright . dont start hacking on your buffer spring or taking weights out of the buffer , that is not a legitimate fix . the larger bore makes it hard to over gas a blackout carbine and if all else fails the gas port can be opened up with out ill effect to sub-sonic or super sonic rounds . I have 3 different 300 blackouts an 8.5 inch pistol , a smith and wesson 16 inch carbine and a remington 700 which cycles everything fine of course . I have helped several friends and familys put together blackouts and they all run just fine .
 
I read on m4carbine.net that the consensus is pistol length too. I guess for the time being I don't have a suppressor and with them not legal at the present time, there's no use shooting subsonic rounds. Would shooting supers be to much gas with a pistol gas system? And then if shooting supers with pistol gas system and with a suppressor?

suppressed pistol gas gun shooting 110 grain varmageddons at 2200 fps . the ground hog seemed to think they worked well.