New Custom AR "Frankengun"

AR/M4 Custom Build Forum
1

I thought I’d post some info and pics of the new AR I picked up today. Largely based on my readings here at M4C, and some suggestions from gotm4, I have what I think is a pretty awesome rifle. Since I lack the tools and the talent, gotm4 at Virginia Arms put up with my onslaught of questions, procured all the parts, and assembled the upper and lower for me.

I have two 16" rifles, one mid length and one carbine, both with Aimpoints, lights, etc. in what is essentially a CQB type setup. I wanted this rifle to be geared for a little more reach.

Here are the specs:

  • VLTOR MUR-1 billet upper receiver
  • Sun Devil billet lower
  • Magpul stuff - trigger guard, rail covers, PRS stock, MIAD grip
  • BCM bolt carrier group
  • Leupold Mark 4 1.5 - 5x with LaRue SPR 1.5 Mount
  • Harris swivel bipod and a LaRue mount to hold it on
  • Stag lower parts kit, RRA two stage trigger
  • PRI Gas Buster CH
  • YHM Phantom FH
  • DD Lite 12.0 rail
  • Troy flip up front and rear BUIS
  • CMMG 18" SPR 1x8 twist chrome lined barrel with mid-length gas port

Have not shot it yet, but I can say it’s awesome. Here are some pictures.

An overall shot. Excuse my photos, I take sucky gun pictures. Unreal to me how hard they are to take.

Closeup of the Sun Devil and Vltor parts. This SUn Devil is a Gen3 part with the textured grip on the front of the Magwell and the tensioner to remove upper and lower play. However, the two parts fit together perfectly - ZERO play in them whatsoever as it is.

I was worried I’d need the extended eye relief mount, but I actually had to move the mount back on notch to get proper eye relief with the PRS stock. Once set, it’s very comfortable.

gotm4 had the gas block re-profiled to fit under the DD rail. With the mid length gas system, the result is a really clean look. Rail, then barrel. I like it.

Close-up of the other side. I have to say the look of the MUR-1 receiver is pretty cool. The Vltor logo and the flag on the other side - how cool is that? :slight_smile:

On last view. Yes, it’s on top of my 7 year old’s mini-pool table.

Anyway - thanks for viewing. I’ll let everyone know how it shoots - hopefully this weekend provided the weather holds.

And thanks again to gotm4 at Virginia Arms. Quick turnaround, great work and overall great service at a great price.

2

Looks like it has a purpose! Nice:cool:

3

I’m glad you like it. I sure do. :smiley:

4

Nice rifle. How do you like that optic?

Been thinking about adding a variable power optic myself, but still don’t know as much as I need to before getting one.

5

Very nice! Gotm4 helped me with my first and second builds; he’s a good guy!

My first also used the Vltor MUR upper, and mated to my Rock River lower, it’s got less than zero play! The fit is so perfect I have to gently tap the takedown pin in.

Gotm4, thanks again for your help with my lightweight yesterday!! :slight_smile:

6

Very nice.

I’m in a middle of similar build.

Paul

7

I have not shot the rifle yet, hopefully tomorrow. I like the SPR recticle on the Leupold - illuminates nicely and the I think the ring will make for quick close range shots. My eyes seem capable of doing both eyes open at the 1.5x setting with ease.

Unfortunately, at the Rivanna Rifle and Pistol Club, the 100 yard range is closed all month for construction of some sorts. So I will be confined to the 25 yard plinking range. :mad: But at least I’ll get to function check the rifle and get the scope at least partially sighted in.

8

OK, I had the chance today to visit the range and put some rounds through this rifle.

All I can say is that it performed flawlessly. I could only shoot 25 yards on the plinking range since the high power rifle range is undergoing some construction work, so I won’t call the rifle “sighted in” yet until I get some more distance. Using el Cleapo Wolf ammo and Guat surplus it made one tiny group at that range. I’ll splurge for some top quality match ammo once I can get the back on the 100 yard range.

I used PMags, Bushmaster 20 round mags, and a Brownells aluminum 30 round mag, all with Magpul followers and everything worked great.

9

It constantly amazes me that someone who builds a $2500 gun will run the cheapest possible ammo.
I don’t even have that fancy of an upper, but I won’t run crappy ammo through mine.

This is much akin to running arco 87 gas in a ferrari…

10

xxxxx

11

I’m plinking cans at 25yards. I am constantly amazed at how many people want to spend a buck a round to nail soda cans. Ammo snobs.

What’s crappy about it? I’ve shot thousands of rounds without a single problem. Excuse me if I’m not buying match grade ammo to shoot at 25 yards.

Thanks for your opinion.

12

Not sure how to take that.

13

Doh, good point…

14

It’s a chrome lined barrel.

15

That it is.

16

xxxxx

17

I agree. WOA would have been much better choice.

That is what I used in my first SPR build.

YMMV

18

I’m confused. Did I miss something on the forum somewhere? Shooting a couple of boxes of Wolf forever ruins the accuracy of the rifle? Or am I misunderstanding you? :confused:

I read up on this forum on Wolf ammo and the general feeling I got was that if it shoots OK in your rifle that it’s fine for plinking. Unfortunately, that is all I can do right now - my club’s high power rifle range is closed and I wanted to at least function check the rifle.

As for barrel choice - I am sure that the White Oak barrels are more accurate. I wanted a chrome lined barrel that would last a long time, and these barrels were GENERALLY well received by many, but not all folks. Seriously, there is NO CHANCE that I can even out shoot this rifle as it. Zero. None. I am just not that good. Maybe someday with more practice.

Plus, it’s not like I can’t re-barrel later if I feel the need.

I was suprised that people jumped on me for using cheap ammo for what was plainly an informal, 25 yard soda can session. I bought a bunch of Federal ammo too, but want to save that for when the high power rifle ranges open back up.

19

Don’t let them sweat you Mike. You’re rifle is still VERY accurate. You’re only shooting a 1.5-5x scope on it. I doubt that anyone on this board can shoot it and see a difference between a WOA barrel and you’re chrome lined barrel using your current 1.5-5x scope. If you were using a 3.5-10x (you might see a difference at 200+yds), 12-42x (surely you would see a difference at 200+yds).

FWIW I’ve assembled a stainless barreled upper for a co-worker than shoots .221" groups with 60gr Hornady VMAX. And I’ve assembled uppers with chrome lined barrels that shoot .5" groups with Black Hills 69gr blue box. So it really boils down to how accurate is accurate enough?

What you have fills you’re needs quite well, not quite how I would set it up, but a good set up none-the-less.

If it were mine I would set it up a little differently. I would use a 2.5-8x Leupold scope in a SPR-E mount (with a JP sight on the SPR mount) and a VLTOR E-MOD stock but that’s just me. I like a little more power on a longer than 16" barrels and to me the PRS is too heavy.

20

You know I noticed something interesting. This new rifle is MUCH more balanced and easy to handle then either of my RRA 16" rifles.

Both the RRA rifles seem very, very front heavy. The carbine has a YHM FF rail, ACE SOCOM stock, the middy has a DD 9.0 Lite rail and a milspc CTR.

Is this because the RRA barrel profiles are much heavier? Or does the heavier PRS offset the weight of the 18" barrel better?

I was sort of expecting the opposite - the 18" barrel with the 12.0 rail to be more front heavy, but that’s not the case. Good for this rifle, but it’s made me question the other two.