Planning out my first AR upper build

bllistc

Sergeant of the Hide
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Mar 1, 2019
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I've built a handful of lowers but I'm getting stuff together to build an upper for the first time. Probably gonna use it mostly to practice shooting steel out to 600-800 yards and get some experience with reading wind (already have a .22LR trainer) and possibly for 3-gun but I think it might be a bit heavy. Picked up a blem BCM upper so far. Here's what else I've got in mind:

Criterion barrel from CLE with matched bolt or
Rainier arms super match barrel
WOA SPR barrel

All in 1/8" twice with 223 wylde chamber

Superlative arms gas block

Geissele mk14 handguard


Looking for advice on barrel length (I'm thinking 16" or 18"), gas system (carbine, intermediate, rifle), barrel profile/contour, pinned vs set screw gas block, as well as any alternative recommendations you guys might have as far as parts. Probably looking to spend less thank $800 total but that not set in stone. Just want a reliable, quality rifle.

Thanks!
 
Following your thread. I would like to build something similar but also kind of a truck gun for coyotes bas well as use in carbine/and shooting out to 800-1000. I shot m-16/m4's in the marine corp and owned a bushmaster varmiter for a while. All my other rifle experience comes from precision bolt stuff. No idea about gas blocks or system lengths or the other nomenclature I hear thrown around.
 
My son just turned 11 a couple weeks ago and just built his first AR. We put a WOA SPR 18" barrel in it. Put about 100 rounds through it last weekend breaking it in. Using my 60gr vmax load I run off my dillon that is 1moa in multiple guns I own. it was shooting 1moa right off the bat. We played around with developing him a 69gr smk load and at max charge with IMR 8208 it was well under 1 MOA. He just finished up loading some more rounds for this morning. I got a felling as he gets more comfortable this gun is going to be very impressive. I say all that to say I was impressed with WOA.
 
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You should snag that Proof SS 18" SPR barrel on here thats NIB for $400 shipped. It's a top tier barrel and $400 is a deal for a top tier cut rifle barrel. 18" rifle gas is what you want.

I'd also spend the $$ for a good rigid receiver like the VLTOR MUR while you're at it. You could get the Proof barrel off the classifieds, a VLTOR MUR1A, a superlative GB, and a Seekins SP3R forend and be into it just under $800 for those parts.
 
You should snag that Proof SS 18" SPR barrel on here thats NIB for $400 shipped. It's a top tier barrel and $400 is a deal for a top tier cut rifle barrel. 18" rifle gas is what you want.

I'd also spend the $$ for a good rigid receiver like the VLTOR MUR while you're at it. You could get the Proof barrel off the classifieds, a VLTOR MUR1A, a superlative GB, and a Seekins SP3R forend and be into it just under $800 for those parts.


I'll go take a look. Forgive my ignorance but how much does a matched bolt matter when it comes to getting a barrel? That was one of the things i was looking for when picking out a barrel.
 
I'll go take a look. Forgive my ignorance but how much does a matched bolt matter when it comes to getting a barrel? That was one of the things i was looking for when picking out a barrel.

Given the set spec for AR's, as long as you're buying high quality stuff I would not worry. I would still check headspace to confirm it's ok, but the top shelf stuff is all going to be machined to tight tolerances so you most likely aren't going to have any fitment issue or a huge headspace or anything. On large frame stuff it's a different story though.

If you can swing $300 for a BCG the LMT Enhanced is the best out their IMO. Good luck finding one in stock right now but word is the next batch is shipping to dealers soon.
 
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Given the set spec for AR's, as long as you're buying high quality stuff I would not worry. I would still check headspace to confirm it's ok, but the top shelf stuff is all going to be machined to tight tolerances so you most likely aren't going to have any fitment issue or a huge headspace or anything. On large frame stuff it's a different story though.

If you can swing $300 for a BCG the LMT Enhanced is the best out their IMO. Good luck finding one in stock right now but word is the next batch is shipping to dealers soon.


Yea I was considering that too. I've got an LMT 308 and I was going back and forth between building this AR or just buying a small frame LMT rifle.
 
Rifle length gas system is going to be the easiest shooting.

I run rifle length gas systems on 18” and 16” guns. In comparison a carbine gas system feels more brutal in comparison.

Use a clamp on gas block that is adjustable. That you can tune it to reduce felt recoil, reduce gas in the face and reduce the amount of crud in the receiver. You can run a lightweight bolt carrier as well with an adjustable gas block. I make lightweight buffers for my lightweight guns.

I have seen a lot more setscrew gas blocks have issues with coming loose than clamp on blocks. Pinned gas block is best but finding an adjustable gas block that can be pinned might be difficult.
 
Some vendors sell a matched bolt with their barrels. If you buy from one of them. No reason not to buy the bolt there. They will check it before shipping. Otherwise you can pickup a set of go-nogo gauges for $80 bucks and its not a bad thing to have around. Very unlikely high end stuff will be out of spec. On the flip site I would hate to have an issue with quality stuff or not because I was too cheap to spend $80 bucks.
 
If you run an 18”, it will be a good blend of velocity for mid distance and it will be pretty workable for 3G. Also like the Vltor upper. Running them on two of my rifles and they have done pretty good. Check with JP for a carrier and bolt. They are a little pricey, but they make good stuff, and the bolt should headspace properly. Good luck with your build. Sounds like you are off to a good start.
 
I will say that I put together a BCM blem upper with a WOA spr barrel, a mk8 13" in black, and its a shooter! but im shooting 53gr vmaxs through it. The mk14 is nice cuz its slim and light weight. but if I was to do that 16" build again id go with a mk8 rail. and im looking for a price on mk8 in ddc that's right too buy right now to change out for the mk14 that installed! in a few weeks im gonna reload some mk262 loads for that spr build and will post my 100yd results if you can wait til then
 
I will say that I put together a BCM blem upper with a WOA spr barrel, a mk8 13" in black, and its a shooter! but im shooting 53gr vmaxs through it. The mk14 is nice cuz its slim and light weight. but if I was to do that 16" build again id go with a mk8 rail. and im looking for a price on mk8 in ddc that's right too buy right now to change out for the mk14 that installed! in a few weeks im gonna reload some mk262 loads for that spr build and will post my 100yd results if you can wait til then

Yea that'd be great. I'm not in a rush to build this right away so I'll probably wait till I see some decent sales on the geissele rails.
 
I have a bit of an AR bug and have built quite a few. All of which I still own and shoot. Anywhere from 10.3, 11.5, 12.5, 14.5, 16, 18, and 20. At first I built the 18’s and 20’s for the exact reason you have listed, longer range. Having said that I have taken my 14.5’s and 16’s our to good distances as well with just as good of luck. Going forward I doubt I will be doing many builds over 14.5. If you run a suppressor then keep that in mind as well when selecting a length. Nothing beats the maneuverability of the shorter barrels. A few inches may not sound like a lot, but it makes a difference.
With your choices above I would do a 16” barrel. I have a Ranier arms super match barrel in an 18” build. They are great barrels, but not sure if they are better then options half the cost. I have had fantastic luck with Ballistic Advantage barrels and their warranty is fantastic. If you don’t think it is shooting as accurate as it should they will replace it. Go with their 223 Wylde premium series that comes in the fluted, bead blasted finish. They have sales all the times and you can easily get one for under $200. I have a second 18” build with one of these barrels and it matches or exceeds the ranier upper build.
You can spend a LOT of money on bcg’s. Head over to spicetac and get a Toolcraft. Great bcg’s for even greater prices of around $90. For ease of easy cleaning get the nitrided version. Do some research on them. A lot of people run them.
An adjustable gas block is really not needed for a rifle or mid length gas system that you can run on 16’s and 18’s. You can certainly grab one, but I think it is unneeded for the most part until you start getting into sbr barrel lengths. If you get a ballistic advantage barrel then you can also order it with a pinned gas block from them. That is what I would do.
The geissele MK14 is a solid rail. You can’t go wrong with that or their MK16 rail.
Long winded explanation, but I just wanted to share my experience. I have spent a LOT of money on some uppers. I have a build with over $1000 in the barrel and bcg alone. When i first started building ar’s my mind set was that the more they cost the better they were. I guess that can be true at times, but I have never had an issue with using the toolcrafts and BA barrels. With a blem BCM upper, BA barrel with pinned gas block, mk14 or mk16 used or on sale rail you will be around $500. Grab a charging handle and muzzle device and spend the rest on optics. Just my opinion.