What would you do next? AR.

[silicosys4]

Here is my first AR build i have been slowly working on, and I'm curious as to where others would go from here. My only real goal so far has been specifically assembling a good AR with a billet upper and lower.
When I started I assumed this would be another 5.56 AR...but I have started reloading since starting this project and now other calibers are on the table. A big bore would make sense for this rifle since its not going to be terribly light thanks to the billet....or so I've been telling myself

So far the build consists of

Cross Machine & Tool billet lower
Vltor mur-1 billet upper
Vltor stock
Spikes enhanced lpk
ALG ACT trigger
BCM full auto bcg
Spikes st-2 buffer

Anyone who wants to chime in on any or all of the following....
What caliber would you pick for this rifle, what barrel, length, twist, gas length, manufacturer, gas block, and handguards would you pick? Why?

Accuracy and reliability are of course the end goals for any caliber and barrel.

Thanks for looking

Edit: I do already have a few AR's in 5.56, so I am kind of looking for something different.

 

[taliv]

if it's your only one, stick with 5.56.

 

[silicosys4]

I should add that as far as the build went, I have no prior knowledge to compare as it was a first for me, but everything went together easily, no problems getting parts or pins in, and this lower has been on another rifle already, a 16" carbine w. carbine gas system, and ran fine for the box or two of rounds I put through it to function test. I like the ALG trigger, it breaks more cleanly and a bit lighter than the standard cmmg trigger that my friend put in his AR. I will say that the CMT lower has a small screw instead of a pin retaining their bolt release, which made for an easy install, although again, I have no comparison. The vltor upper finish does not quiet match the cmt lower, but pretty close.

 

[savanahsdad]

if it's your only one, stick with 5.56.

ok ???? why would you say that ?? I have one AR15 and it's not a 5.56 it's not a build it's out of the box , but if I were to build one it would not be a 5.56 . not when you can pick one up at Wally-world from $499-$1100.

 

[Jackal]

My vote for a 16" midlength pencil barrel from PSA, its made by FN and hammer forged, mine shot right at MOA.

 

[taliv]

relax it's just an opinion.

because the ammo selection for 556 is unparalleled. you can reload plinking rounds in 556 cheaper than any other caliber, using ubiquitous mil pull down powder and projos and once fired brass. you can get extremely accurate factory match loads from lots of different mfgs. you can get military ball, varmint, big game, tactical and lots of different specialty ammo.

plus lots of other reasons if you're building.

 

[LebbenB]

Why not 300 BLK? A 12-16 inch melonited barrel with a 1:8 twist and carbine length gas system. Low-pro gas block. KAC URX III FF forend.

You already have a few 5.56mm rigs and reload for them. No need to buy special mags and 300 BLK cases can be formed from 5.56/.223 brass.

 

[savanahsdad]

relax it's just an opinion.

because the ammo selection for 556 is unparalleled. you can reload plinking rounds in 556 cheaper than any other caliber, using ubiquitous mil pull down powder and projos and once fired brass. you can get extremely accurate factory match loads from lots of different mfgs. you can get military ball, varmint, big game, tactical and lots of different specialty ammo.

plus lots of other reasons if you're building.

oh I was relaxed , I was just wondering why someone would go through all the work to build a full AR15 in 5.56 when you can get them off the shelf , I can see building a lower to save some cash or to have a top of the line trigger and then buying uppers in whatever cal. but when you said stick with a 5.56 , I didn't see why , now I see it was just for the ammo ... ok thanks, but a few month back for many months that was one of the hardest cals. to get , and I found lots of food to feed my Ar15 , and nothing wrong with the 5.56 some day I'll get one , already got dies , bullets and brass for it

 

[savanahsdad]

Why not 300 BLK? A 12-16 inch melonited barrel with a 1:8 twist and carbine length gas system. Low-pro gas block. KAC URX III FF forend.

You already have a few 5.56mm rigs and reload for them. No need to buy special mags and 300 BLK cases can be formed from 5.56/.223 brass.

then get a threaded barrel for a can

 

[TBH]

6.5 Grendel cal. Mine is 6.5 CSS. Now you can get Les Baer's 6.5 LBC.
Nice cal, good selection of bullets if you reload. Low recoil but can still shoot 5-600 yds. I would also suggest looking at the 6x45(?). Again if you reload, you neck up .223 brass and have a fairly impressive 6mm AR.

 

[taliv]

I was just wondering why someone would go through all the work to build a full AR15 in 5.56 when you can get them off the shelf

mostly to get the optimal configurations you can't buy off the shelf. e.g. my latest build www.thehighroad.org/showthread.php?t=713477

 

[LebbenB]

then get a threaded barrel for a can

Or use an AAC 51T flash suppressor and 762-SD-N, like I did with mine

 

[savanahsdad]

mostly to get the optimal configurations you can't buy off the shelf. e.g. my latest build www.thehighroad.org/showthread.php?t=713477

nice paint, I thought it was dipped,

 

[taliv]

it was dipped

 

[savanahsdad]

it was dipped

yep it looks dipped, I see in that post someone said paint and I didn't see where you had corrected him,

op: can we get a hint of what cal you are leaning to ? and what this AR might be used for

 

[silicosys4]

Well, right now I'm leaning reeeeally heavily towards .300 blackout. I have a few thousand 5.56 brass, and reload .308 for an FAL and a hunting rifle, as well as 30-06 and 30-30, so I am actually pretty well set up for the blackout as far as various projectiles. The rifle will be used mostly for range use with some possible deer hunting use, less than 200 yards. The gun will likely never be suppressed or be used with bullets heavier than 150 grains.

Although one of the 6mm cartridges would be interesting, but that is a lot of extra money for dies, brass, and projectiles that I don't necessarily need to spend, for little to no gain for my purposes....maybe a hundred or so extra yards of plinking range over the blackout is all it would do for me, since I would rather use my .270 for any hunting where I would expect a 200+ yd. shot.
Although I just looked into 6.5 Grendel, and it appears I can fire form 7.62x39 brass into 6.5 Grendel, although with reduced case capacity....but that would give me an excuse to start reloading for my sks and ak as well...better ballistics...food for thought, although the prospect of buying a couple thousand brass and projectiles is daunting.

.458 socom would be fun in theory, I like the ability to get .45-70 ballistics out of an AR, and I like that you can load up to 500 grain solids at something like 1100 fps and have a genuine short range dangerous game rifle. It would be fine for up to 200 yard on deer with lighter bullets.... but reality kicks in when I think about the cost of those big bullets and brass, and the lack of dangerous game hereabouts, and my intended use....I start leaning back towards the .300 blackout as more practical.

I would like to go with an 18" barrel, something not too heavy but moa accurate if possible, mid length gas system (unless .300 would be better with a different length), free float handguards, low profile gas block.

 

[savanahsdad]

you hunt with a 270win ...... have you looked at the 6.8MSPC ? a 270 short, for deer that's where I would lean , for a shorter range (-100) Id go with the 300blk, but at 150 or so Id go with the 6.8. but then I would take a 270 over most 30cals, (love my 270's) I almost got an AR in 6.8 but I wanted a bit more range

so I vote 6.8 with a fast twist for heavy bullets

 

[meanmrmustard]

ok ???? why would you say that ?? I have one AR15 and it's not a 5.56 it's not a build it's out of the box , but if I were to build one it would not be a 5.56 . not when you can pick one up at Wally-world from $499-$1100.

What AR at Walmart in 556x45 costs $499. Notice the lack of a question mark.

 

[LebbenB]

Well, right now I'm leaning reeeeally heavily towards .300 blackout. I have a few thousand 5.56 brass, and reload .308 for an FAL and a hunting rifle, as well as 30-06 and 30-30, so I am actually pretty well set up for the blackout as far as various projectiles. The rifle will be used mostly for range use with some possible deer hunting use, less than 200 yards. The gun will likely never be suppressed or be used with bullets heavier than 150 grains.

Although one of the 6mm cartridges would be interesting, but that is a lot of extra money for dies, brass, and projectiles that I don't necessarily need to spend, for little to no gain for my purposes....maybe a hundred or so extra yards of plinking range over the blackout is all it would do for me, since I would rather use my .270 for any hunting where I would expect a 200+ yd. shot.
Although I just looked into 6.5 Grendel, and it appears I can fire form 7.62x39 brass into 6.5 Grendel, although with reduced case capacity....but that would give me an excuse to start reloading for my sks and ak as well...better ballistics...food for thought, although the prospect of buying a couple thousand brass and projectiles is daunting.

.458 socom would be fun in theory, I like the ability to get .45-70 ballistics out of an AR, and I like that you can load up to 500 grain solids at something like 1100 fps and have a genuine short range dangerous game rifle. It would be fine for up to 200 yard on deer with lighter bullets.... but reality kicks in when I think about the cost of those big bullets and brass, and the lack of dangerous game hereabouts, and my intended use....I start leaning back towards the .300 blackout as more practical.

I would like to go with an 18" barrel, something not too heavy but moa accurate if possible, mid length gas system (unless .300 would be better with a different length), free float handguards, low profile gas block.

300 BLK reaches complete powder burn at about 8 inches or so. Knowing the paperwork hassle involved in going the SBR route from owning suppressors, I chose to go with a 16" barrel and a carbine length gas system though there is no substantial accuracy advantage to be gained by going with a longer barrel. Depending on the load, the round is effective out to 300m. Anecdotally, my longest shot with it (to date) was 220yds on a wild pig. Load was a 135gr SMK over 17.3 grs of Lil' Gun. Hit it just behind the shoulder and it ran about 10 yards and then fell over.

Like you, I have thousands of 5.56 cases and 7.62/.308 bullets, so 300 BLK was something of a no-brainer for me.

 

[Lennyjoe]

I built a blackout AR specifically for a suppressed, sub sonic load shooting rifle and also have one in 6.8 SPC. The Blackout is idle waiting on the stamp for the suppressor (6 months in so far). My 6.8 has an 18" Bison barrel and is a tack driver using SMK 115 gr and H-335 but noses over hard ~ 250m.

 

[gotigers]

Taliv is spot on. 5.56 because of the great selection of ammo from $.30 around to $2 and it is everywhere.

I would get either an 18" rifle or 16" midlength in a medium contour. Both cycle smoothly and reliably. The medium contour will handle heat better and will keep more consistant groups while not be too heavy.

Either a stainless 223 wylde chamber, 1:8 twist, maybe fulton armory (criterion), Wilson, WOA, etc

or

Daniel Defense or FN chrome lined 1:7 twist.

Add to that a low profile gas block and a 12" or 15" tube style free float that has a top rail. Seekins, Spikes, Noveske, Wilson, Midwest Industries, Centurion. They are all very good. Just decide on the OD of the tube and weight.

 

[atomd]

The MUR upper is not billet it is forged.

I would go with the 300 blackout. Since you already have brass you can turn into 300 brass easily and you probably already have bullets you can use....it's a piece of cake. I'd go with a 14.5 barrel, pin on a battlecomp 1.5, and maybe a Geissele 13.5" SMR or a Noveske NSR. Since you have a little bit more weight with the billet lower and the mur upper, that somewhat lighter stock and a lighter setup like the SMR/NSR will keep the overall weight down a little bit. Noveske makes a 14.5" 1/7 pistol gas that comes with the block already pinned and ready to go...it's expensive but it's nice. I might order that barrel myself now that I think about it. Since you said accuracy is most important, the barrel is the place to put the $ anyways. Rainier has some barrels in stock to choose from and there's a few good options. If it were mine I would change that grip too...just looks out of place.

 

[Tony k]

Fill a niche

I'd go with the 300 AAC because it sounds like it would fill a niche. You've brought up your 270 that you prefer for deer hunting and whatnot, and you've got your stable full of 5.56 ARs. The 300 AAC fits somewhere between to two calibers power-wise.

 

[gotigers]

I don't care for billet for 3 gun or any kind of defense. I want my ARs as light weight as possible. Billets are much heavier. Even the MUR is heavier than a foreged upper. If you're not carefull you can have built a very heavy plinker. lol.

I do like billet for precision rigs. I want the weight in a bench AR.

My next 3 gun AR will be all forged. Aero Precision forged slick side upper and Mega forged lower.

 

[tuj]

Geissele trigger.