Lite Weight Build

KnotRight

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I have a friend that wants me to help him build an AR-15 in 300 BO. He has going through some chemo issues and want the gun to be as lite as possible.
He is also looking for a drop in trigger with a break around 3# (single stage???).
Money is an issue but he said that he wants this to be as good and a $1,500ish store bought rifle.

Looking for suggestions on all parts and I know that there is a bunch of triggers out there and will have a few different ones to pick from . BTW, he is planning on hunting with the gun and has a multi-can on order.
 
So, a 16" rifle?

Barrel is going to be key in keeping weight down. Something like this would be a good place to start.
https://faxonfirearms.com/16-gunner-300-blk-carbine-length-4150-qpq/

Yes I am figuring on a 16" barrel but he is going to look at my 16" and 10" barrels. If he goes with the 10" he is going to need a Tax Stamp because he wants the can to be removable.
There a carbon fiber barrel and forehand grip but know nothing about them or who makes them. I saw an AR-15 223 with a carbon fiber barrel a couple weeks ago.
 
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I am NOT the AR know all.

I built one in 556, 16" that comes in at about 6#'s

Pencil barrel. With that comes heat dissipation. I typically don't run more than a mag or two before I let it cool down. I really haven't noticed any accuracy issues but I don't push it too hard either. It's my favorite rifle.

You may get more barrel if it's shorter but that gets you into pistol or NFA.
 
SpOOks, the guy is going to use the gun for hunting and do not thing that he is going to shot a lot at one time. He even asked if there is 10 round magazines for the 300 BO.
 
I built a 16" Aero Precision with their enhanced upper, stainless Ballistic Advantage barrel, their lower, and the rifle ended up at 6lbs, which is 2lbs lighter than my comparable Barnes. Not 300BO though.
 
If a SBR stamp can be filed, that would make lighter weight very easy. Not sure of legalities of SBR or Pistol hunting.
But it is possible to get a pretty light gun for an affordable price even at 16”, even without carbon barrels.
The carbon barrels are awesome, but pretty spendy.
 
I’ll throw out V Seven’s LR lightweight receiver set to start with ... it’s milling away in certain areas does shave weight. Then use a titanium barrel nut (V Seven comes to mind) to hold a carbon fiber barrel (Wolfpack Armory our of WV has a great barrel for decent price). Back it up with a Missionary First Tactical Minimalist buttstock and you have shaved a nice chunk of weight of an AR. You can go carbon fiber for the handguard or go with a lightweight M-Lok again with V Seven , DD or such. You can build a sub 5 lbs carbine pretty easy but it does cost money to shave pounds.
 
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@BigWaylon and others:
After spending some time on the phone with the friend that want the 300 BO, I think what he would LIKE to have is a sub 5# gun. Can be done but topped the 2K mark. I think that I talked him into a 9 to 10 BA barrel with a good lite weight cutout hand-guard. Going to have a 6" can on the business end and maybe a SB3 brace. Will be looking for a drop in single stage trigger (straight) that can be set between 2.5 and 4 pounds for hunting. Not sure what lower would be best and what BCG. I know that the BCG needs to be plated/coated.

I might have 1 or 2 stripped lowers PSA here here if he can not find one better. Truth be told, I have built 5 ARs with PSA lowers and have not had any problems.
Not sure it pays to go crazy on the pins and buffer spring (maybe a combo spring buffer). I would like to put anti-walk pins in the lower.
Until his form 4 gets here I will stick a good break on the gun.

I think that this could be done between $1,000 to $1,200. The he is talking about a 2 MOA red/green dot and I figure a mid-price one would be around$375.

The build is on me as a friend.

Suggestions for lowers, drop in trigger and 8" cut out hand guard.
 
knock off a couple ounces - go 14.5 pencil barrel and pin/weld a muzzle brake to go over the 16" mark ?
 
What ranges & game is he gonna be shooting? Might could shave more weight off with a 8" barrel & should still be good for deer at 100 yds.
 
Which silencer? And (if there’s an option) which mount?
 
it's been covered here, but the easiest way to shave weight off an AR that isn't going to ever see mag dumps or full auto on a continuous basis (99% of all ARs) is barrel weight reduction.
Of course I have to pimp Faxon as well since they have been great in warranty claims as well as being great quality / value. I think the gunner profile is nothing short of awesome.
I would highly recommend their 10.5-12" gunner in any chambering. I have an 18" Gunner 5.56 rifle that weights 7.5lbs with optics, a sling and full 30rd Pmag, it's my favorite.

Under 5# with any type of sights besides buis is going to be.....expensive
 
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Check out MAG Tactical Magnesium Lower receivers....

About 30% lighter than aluminum and stronger as well.
 
The thing is, 30% of 8.5oz is 2.5oz. You could easily eliminate that much by just removing Magpul BUIS. Weight reduction (in any hobby) is a game of diminishing returns. Ask any backpacker!
 
it's been covered here, but the easiest way to shave weight off an AR that isn't going to ever see mag dumps or full auto on a continuous basis (99% of all ARs) is barrel weight reduction.
Of course I have to pimp Faxon as well since they have been great in warranty claims as well as being great quality / value. I think the gunner profile is nothing short of awesome.
I would highly recommend their 10.5-12" gunner in any chambering. I have an 18" 5.56 rifle that weights 7.5lbs with optics, a sling and full 30rd Pmag, it's my favorite.

Under 5# with any type of sights besides buis is going to be.....expensive
https://www.brownells.com/search/index.htm?avs|Newsletter_1=WWSD+Products
No kidding.
I just parted out what I think the gross price/weight is:
https://docs.google.com/spreadsheets/d/1XhIp9bLIn8HyC3QtlakiOYYEwilfK1ews4CFUuk6RJk/edit?usp=sharing

Price comes to $1263.87
Weight is 4.697375 lbs

Might be missing some parts. Some parts are out of stock. The lower is an estimate, hasn't been released yet. The big problem is Faxxon doesn't make a pencil barrel in 300blk. They have the gunner profile, but its in 16'', not 14.5''. Still less heavy than anything else I could find.
 
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The big problem is Faxxon doesn't make a pencil barrel in 300blk. They have the gunner profile, but its in 16'', not 14.5''. Still less heavy than anything else I could find.


How about the PROOF Research 12.5" , or 16" carbon wrapped barrel in 300 Blk?
 
How about the PROOF Research 12.5" , or 16" carbon wrapped barrel in 300 Blk?
I don't think it's worth it.
Assuming he's not using a pistol, and didn't want to have a 4'' muzzle brake, there's only the 16''.

It costs $726 more, and weights .3 ounces more.

https://proofresearch.com/barrels/ar-type/

If OP wanted 223, there's lighter weight barrels, since pencil is doable, and there's more support for 14.5''
 
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I know you can hunt in NC with an SBR. I assume AR pistol is fine? (Pretty sure I've seen multiple people mention doing it)

not sure if build being discussed is for somebody in GA or not...
 
I know you can hunt in NC with an SBR. I assume AR pistol is fine? (Pretty sure I've seen multiple people mention doing it)

not sure if build being discussed is for somebody in GA or not...

legal to hunt private land in NC during firearms with any firearm, period. Public land generally the same except some Army Corps land wont let you carry a sidearm openly. None have barrel length restrictions.
 
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Cmc trigger will get.you a good crisp trigger.

12.5in is about optimal for 300 blk. If he does not want to do a form 1 then go pistol with sba3.

Is he planning on full power ammo or subs?
 
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I know the wwsd 2020 has been mentioned above.

They are "hoping" to start shipping them out by the end if this month.
Pretty excited .
 
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WWSD2020 finalized, to be released soon.

4.96 lbs.
 
InRangetv wwsd (what would Stoner do) project might give some ideas. They got their finished version down to roughly 5 pounds.
Cousin Jerry built a 5 pound pistol. He tucks the muzzle in his jeans watch pocket and sticks the butt under his arm and puts on a vest and goes everywhere completely unnoticed.
 
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