.300 blackout rebuild

kentuckycoyle

Private
Minuteman
Jul 22, 2014
23
0
Anderson, KY
I built a .300 last year for very cheap. I'm wanting a better one now but not a new one. I just want to rebuild this one. I plan on taking a long time to build this so money isn't going to be an option. So ooo really what I'm asking is for everyones input on what parts they like for the AR platform and a .300 barrel.
 
Well its AACs round, so anything aac is going to be killer in a .300 build. Their barrels are awesome though expensive. They have really nice complete uppers. Noveske has cool stuff for the .300 and knights has sr-30 uppers. Choose whatever barrel you like and build the rest with top quality regular AR-15 parts.
 
Seekins IMRT upper and the MCSR 15" rail system coupled with a BCM BCG and a PRI gasbuster or BCM mod 3 charging handle and a seekins or pri low profile adjustable gas block

The only changes I would make to that is if you prefer the MSC3 rail system or the BAR (which is full quadrail)
 
Well its AACs round, so anything aac is going to be killer in a .300 build. Their barrels are awesome though expensive. They have really nice complete uppers. Noveske has cool stuff for the .300 and knights has sr-30 uppers. Choose whatever barrel you like and build the rest with top quality regular AR-15 parts.

I disagree with that entirely. The same could be said of the Handi Rifle, it too is AAc and it is worth the $350 they cost new, that's about it, definitely not "killer."

Are you shooting your 300 suppressed or no? If so, they get dirty, dirty, dirty. Mine runs a chromed bolt in a side charger with the gas block turned off for quietest possible operation (8.1 gr of lil gun over a 208 Amax is great, but not enough gas to run my bolt reliably.)

Also be aware that as the barrel gets shorter, the sound level goes up. I had a 10.5 for awhile, even subsonic with suppressor, it was loud. Adding 6" of barrel took MUCH of the bite off the report.
 
I disagree with that entirely. The same could be said of the Handi Rifle, it too is AAc and it is worth the $350 they cost new, that's about it, definitely not "killer."

And their barrels are worth what they charge for them. You said it costs what its worth?!?! That's so strange!!!! They come with the gas system and thread protector. Their uppers come with KAC urx 3.1 rails already on them. They make good stuff. I guess its good thing the OP isn't building a handi rifle or I would be worried about your opinion.
 
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I was addressing the statement, "Well its AACs round, so anything aac is going to be killer in a .300 build." and disagree with that statement - perhaps I should have been more clear.

I've not been impressed enough with AAC's other stuff to worry much about their AR stuff, since very reputable and quality parts can be had for less money. I don't value the name on it just because they took a 300 Whisper and made the most minor of minor changes and called it a Blackout.

To each his own.
Carry on.
 
I built a .300 last year for very cheap. I'm wanting a better one now but not a new one. I just want to rebuild this one. I plan on taking a long time to build this so money isn't going to be an option. So ooo really what I'm asking is for everyones input on what parts they like for the AR platform and a .300 barrel.

What does "better" mean? What specifically are you unhappy with? Are you shooting supers and subs? Want to SBR?

I have a build based on the 8.2" Noveske that I run suppressed and unsuppressed as well as an upper I built using a carbine length gas, 16" Wilson combat that I cut to 12.75" and run suppressed only. Both, however, were built for specific reasons. Any additional detail you could provide with respect to what you are trying to accomplish would help get you the advice you seek...
 
How does the Seekins 16" barrel work for ya? Its a carbine gas system right? How does it handle supersonic and subsonic loads?

I like the barrel. Its torqued pretty tight (70lbs) becuase the hand guards and barrel nut were very cheap, but still holds about 1" group at 150 yards. Thats not benched so I'm sure with a Geissele or Timney trigger and I better (tighter tolerance) upper and bcg it would perform amazing.
 
What does "better" mean? What specifically are you unhappy with? Are you shooting supers and subs? Want to SBR?

I have a build based on the 8.2" Noveske that I run suppressed and unsuppressed as well as an upper I built using a carbine length gas, 16" Wilson combat that I cut to 12.75" and run suppressed only. Both, however, were built for specific reasons. Any additional detail you could provide with respect to what you are trying to accomplish would help get you the advice you seek...
My suppressor came in three days and I have not shot through it yet nor have I shot subsonic rounds but I plan on it soon. To answer your question it performs fine, I just don't like the play between the upper and lower or the gritty trigger pull. The buttstock also has quite a bit of play and the barrel is extremely tight because of the cheap hand guards not lining up perfectly for the gas tube to go through at 50lbs like I'd like it. I really don't know a whole and I'll never claim too. I just thought building a .300 would be fun and I was right. It was a blast and now I'm looking to spend more money while having fun improving it
 
To answer your question it performs fine, I just don't like the play between the upper and lower or the gritty trigger pull. The buttstock also has quite a bit of play and the barrel is extremely tight because of the cheap hand guards not lining up perfectly for the gas tube to go through at 50lbs like I'd like it.

There are small gap-fillers that can address the "play" between upper and lower, the trigger is an easy swap, as is the buttstock, and you can install a new floating quad rail easily too, with a new barrel nut that might line up better. I don't think there is any issue with your barrel tightness, that is exactly why the range is so broad.
So, if yours is shooting to your satisfaction, you can clean up what you want for around $500 tops. Or you can start over on a new one. Be aware that most lower parts kits have crappy triggers, even those that claim NM 2-stage will be nowhere near as good as a stand-alone aftermarket trigger from a reputable trigger maker.

Yours is a classic case of buying parts on the cheap for the first round, then wanting better stuff later. Most of us who have been doing this awhile have a drawer or closet or small shed filled with swapped parts from previous builds. With a cheap lower or 2, I could build complete guns from stuff sitting in boxes under my reloading bench, it is the nature of learning. You can try selling the old stuff, or just sell the entire gun and start from scratch.

The fun isn't in the building, it is in the perfecting, in my opinion.
 
There are small gap-fillers that can address the "play" between upper and lower, the trigger is an easy swap, as is the buttstock, and you can install a new floating quad rail easily too, with a new barrel nut that might line up better. I don't think there is any issue with your barrel tightness, that is exactly why the range is so broad.
So, if yours is shooting to your satisfaction, you can clean up what you want for around $500 tops. Or you can start over on a new one. Be aware that most lower parts kits have crappy triggers, even those that claim NM 2-stage will be nowhere near as good as a stand-alone aftermarket trigger from a reputable trigger maker.

Yours is a classic case of buying parts on the cheap for the first round, then wanting better stuff later. Most of us who have been doing this awhile have a drawer or closet or small shed filled with swapped parts from previous builds. With a cheap lower or 2, I could build complete guns from stuff sitting in boxes under my reloading bench, it is the nature of learning. You can try selling the old stuff, or just sell the entire gun and start from scratch.

The fun isn't in the building, it is in the perfecting, in my opinion.
That's what I'm saying. I want everyone's opinion on what parts I should swop for the parts already on the rifle. What trigger does everyone like, what handguards, etc... I did not know anything about fillers though. I will have to look that up. Thank you for that.
 
AR-15/M16 ACCU-WEDGE | Brownells

I don't use them, but I don't know how much "play" you have.

ENHANCED TRIGGERS | Brownells

In all my ARs.
(I would avoid Wilson COmbat TTU, most have no issues with them, some here have had them wear down and go full auto - which is fun but very, very illegal.)

AR-15/M16 SP3R V2 KEYMOD QUAD RAIL | Brownells

Front rail depends on how you wish to use the rifle and what you "need" vs what you want. I like Seekins and Daniel Defense rails, but have used Yankee Hills and like the newer ones.

AR-15/M16 UBR BUTTSTOCK | Brownells
Most of the Magpul stocks will work for you. I like the UBR because it is heavier, giving a nice offset to that hunk of metal out there on your muzzle.


My updates would be a Magpul UBR, Geissele 2-stage, accu-wedge if you want, and a decent rail: with that, you will have a nice setup and respectable start on a used parts bin.
 
AR-15/M16 ACCU-WEDGE | Brownells

I don't use them, but I don't know how much "play" you have.

ENHANCED TRIGGERS | Brownells

In all my ARs.
(I would avoid Wilson COmbat TTU, most have no issues with them, some here have had them wear down and go full auto - which is fun but very, very illegal.)

AR-15/M16 SP3R V2 KEYMOD QUAD RAIL | Brownells

Front rail depends on how you wish to use the rifle and what you "need" vs what you want. I like Seekins and Daniel Defense rails, but have used Yankee Hills and like the newer ones.

AR-15/M16 UBR BUTTSTOCK | Brownells
Most of the Magpul stocks will work for you. I like the UBR because it is heavier, giving a nice offset to that hunk of metal out there on your muzzle.


My updates would be a Magpul UBR, Geissele 2-stage, accu-wedge if you want, and a decent rail: with that, you will have a nice setup and respectable start on a used parts bin.

Awesome! Im thinking about the Seekins SP3R V3 mod rail. I like the flat bottom for laying on a rail or wall. The can actually isn't all that heavy but I would like a 15" rail so I'm sure that will add a little extra so a heavier but stock would be nice. Your post is exactly what I'm looking for. Some great options. Thank you.
Also I started researching the TTU after you said full auto and saw that it was your post. What exactly failed on the TTU to cause it to go full auto?
 
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On the TTU, I'm not sure. On that thread where I mentioned it, someone said they had seen it too. I started looking online and found a few who said they too had well used TTUs go full auto.

I was disappointed in Wilson (have been a few times in the past year or so) when I called, they said, "We've never seen that or had it happen before..." when there is word online of it. The did replace it with no run-around. The replacement is now in a gun that sees very little range time.

It is a self-contained trigger mech, I'm not sure what wears down, but when it does, it does for good.

And on the 15' rail, I run 13 and 15 on mine, have long arms, like hand as close to muzzle as safely possible, drive the muzzle on target.