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Joelski
19 September 2015, 09:04
I have a 10.5" waiting for the man to greenlight the stock. My question; is that length, in BLK, with pistol length gas system going to be over-gassed out of the box? What about when I add a suppressor? I'm looking at the REECE, threaded directly to the barrel to keep it partially under the rail. Will I need an adjustable gas block? Which buffer weights are appropriate with/without the can? I've tried to find this info, but there isn't as much to be found, compared to more common rounds.

Dstrbdmedic167
19 September 2015, 09:13
First question is do you plan on shooting subs or supers mainly?

tact
19 September 2015, 09:50
An adjustable GB is not needed contrary to some. I'm not using one suppressed/unsuppressed with subs and supers.

Joelski
19 September 2015, 12:41
An adjustable GB is not needed contrary to some. I'm not using one suppressed/unsuppressed with subs and supers.

I heard both ways on that and decided to stop reading and start asking experienced shooters. Are you using a heavier buffer depending, or just a standard carb buffer?

UWone77
19 September 2015, 13:02
I'd just shoot it with a carbine buffer, then increase buffer weights until you find the heaviest buffer the gun will cycle reliably with.

SwissyJim
19 September 2015, 16:55
adj gas block is not needed, but is nice to have to help dial it in. And think about the JP Silent Capture spring if you're going suppressed... the twang will drive you nuts otherwise. Plus you can use their spring pack to dial it in even more. Mine has nearly zero recoil anymore with my sub handloads, the gas blocked closed some, and the spring changed on the JP.

tact
19 September 2015, 16:55
I read probably everything you read as well when I started out with my 300 build. I guess what swayed me was the fact that AAC did a fair amount of development with the round and none of their uppers have an adjustable GB.

UW has good advice about the buffer weight. Mine is using an MVB Arc stock so I'm using their buffer but I believe it is basically the same weight as an H1.

mustangfreek
27 December 2015, 13:33
Bumping and sorta sidetracking...

16" blackout with pistol gas and running mostly supers, what buffer and spring for collapsed setup?

Also will a rifle length tube and buffer run with the bo as I said u think?

alamo5000
27 December 2015, 13:43
I am very new to all this, but I would not put a can up under the rail. Shoot a little bit and that sucker gets H-O-T!!!!

It's a concept that looks good on paper but I wouldn't want it.

Also with my limited experience I would say use an adjustable block and call the rest a day.

Of course please note that I know nothing about .300 BO specifically. I don't know if buffer weights matter on that round or not.

alamo5000
27 December 2015, 13:44
adj gas block is not needed, but is nice to have to help dial it in.

^^^ What he said.

alamo5000
27 December 2015, 14:00
https://www.youtube.com/watch?v=2HzMLvrF6u4

Start watching at 20 minutes in.... that stuff is gets HOT. Under a rail the radiant heat is still going to be really bad.

One mag and you will be up over 500 degrees. Two mags and you're up around 850 degrees based on their test....

cjd3
27 December 2015, 14:13
Never thought about the heat under the guard. The new MI SP hand guards look nice for the application.

gatordev
27 December 2015, 14:54
https://www.youtube.com/watch?v=2HzMLvrF6u4

Start watching at 20 minutes in.... that stuff is gets HOT. Under a rail the radiant heat is still going to be really bad.

One mag and you will be up over 500 degrees. Two mags and you're up around 850 degrees based on their test....

Welcome to #suppressorlife.

P39
27 December 2015, 14:58
Admittedly, I'm no professional at this, nor am I an expect, but I do agree that there's no need for the adjustable GB. I don't have an adjustable GB on either of my BLK set ups. One is a pistol that's running H2 buffer weight with no issues. The other is a 16" carbine gassed, also running H2, no issues. All that said, though......I'm running supers only. No subs, nothing suppressed......yet.

gatordev
27 December 2015, 15:04
Admittedly, I'm no professional at this, nor am I an expect, but I do agree that there's no need for the adjustable GB. I don't have an adjustable GB on either of my BLK set ups. One is a pistol that's running H2 buffer weight with no issues. The other is a 16" carbine gassed, also running H2, no issues. All that said, though......I'm running supers only. No subs, nothing suppressed......yet.

Word. I only have one adjustable gas block, and it's on a piston gun which doesn't actually need it to run. Every single rifle I own runs suppressed without issue. I get the need for them for a "not-in-spec" rifle, but if you buy something that's a known quantity, life is easy without one.

P39
27 December 2015, 15:52
^^^^Agreed.

I'd like to get into a suppressor on the 300BLK pistol I built. I'm just not sure I want to do so without a trust.

SwissyJim
27 December 2015, 17:24
I have my suppressor running under the Seekins MCSR rail on my 300BLK, and to be honest I have never felt the heat. Now granted, I run 90% (or better) subs which do not generate the heat as much, but if subs are the game then go for it. On the other hand, my can on my 5.56 SBR runs HOT. DAMN hot. I can see how it being under a rail (it is not) woudl be a problem.
But really, IMO, the 300BLK should be run subsonic with a can.

alamo5000
27 December 2015, 18:22
I have my suppressor running under the Seekins MCSR rail on my 300BLK, and to be honest I have never felt the heat. Now granted, I run 90% (or better) subs which do not generate the heat as much, but if subs are the game then go for it. On the other hand, my can on my 5.56 SBR runs HOT. DAMN hot. I can see how it being under a rail (it is not) woudl be a problem.
But really, IMO, the 300BLK should be run subsonic with a can.

Straight from experience. No need to look any further.

I have never shot 300 BO super or sub suppressed or not... but I know 5.56 will burn the living shit out of you.

SwissyJim
27 December 2015, 19:09
Straight from experience. No need to look any further.

I have never shot 300 BO super or sub suppressed or not... but I know 5.56 will burn the living shit out of you.
oh yeah... it does run hot. My Specwar556 has some really cool color change lines on it from the heat. I picked up a Cole-TAC suppressor cover directly because I burned myself pretty good by accident just putting the rifle down on the bench (don't let your guard down!!). I've toyed with the idea of cooking some bacon on mine. I even brought home a pair of older firefighting gloves that were past their date for work... and I could feel the heat if I held on too long.

My 300BLK setup (Specwar762) on the other hand is still all pretty and even colored. Hell, I bet I could unscrew it after I shot a couple of mags. But, once again... subs vs. supers, not too mention caliber difference... my .223 handloads take lots more powder than my 300BLK loads do, super-wise.