Thinking about building a SPR/MK12 rifle.

This is the one I have been eying for a while http://www.bravocompanyusa.com/BCM-SPR-Mk-12-Mod-Bravo2X-p/bcm-urg-mk12-2x%20lt13.htm. With a KAC QD Muzzle Compensator Kit

I’m sure that’s a great upper. I’ve never been let down by any BCM upper. Having said that you can get a Larue Stealth URG (includes a BCG/CH) for cheaper and it has a better upper receiver. But you might have a little wait time.

That is true I was looking at them earlier today. The thing is as well the front handguard would be swapped out for a troy for weight saving and I need ambi charging handle (raptor) b/c I’m a lefty.

how is the upper receiver better?

Achieving 2-4" groups at 400-500 yards is a tall order for an AR platform in 5.56mm. I am sure there are going to be many that say they achieve this, and that may be so. However, that is stretching the platform/ammo combination to the EXTREME at that distance. Even Monty LeClaire of Centurion Arms (also bud of Mr. Vickers and top notch SEAL sniper) stated on a Tac-TV episode about the SPR that it isn’t a solid 1MOA rifle. I believe he said that is more of a “marketing” thing. While I own and have seen many AR platforms in 5.56 achieve tiny groups (1" and less) at 100 yards, 1" at 100 doesn’t always equal 2"/200yds, 3"/300yds, etc. I have read reports (footnote here, READ them/not seen this or experienced myself) the LaRue OBR being capable of great feats of accuracy you desire, but again that is a true stretch. For that range, one might want to consider going to a .308. I have also SEEN great accuracy from 6.5 Grendel and Creedmore rounds. Just my .02, good luck. If you consistently achieve what you are after with an AR in 5.56, let me know the secret!

2" was being very over optimistic to say the least lol. I’ve just got a inch to build another AR but don’t want another 16incher and can’t find anything SBR ugh. lol

I understand the quest for accuracy. I myself am constantly doing the same. I always want to squeeze the maximum accuracy out of even my most basic patrol rifles. While stainless steel barrels are obviously the norm for the SPR builds (no chrome lining which tends to be inconsistent, hence, less accurate), I have been looking at some salt-bath-nitride (aka Melonite / commercial name) options. One can get an awesome CHF 4150 barrel, with the above mentioned treatments. Reports say one gets all the accuracy as well as greater barrel life than that of CL or stainless! Of course, I am going to have to find out for myself (an excuse to build/buy another rifle).

Trying to save weight on a SPR? Saving weight in general is fine but is it a SPR or LW build? Consider the trade offs.

From the Larue Tactical website…
“The LaRue Stealth receiver is an improved-version of the currently fielded mil-spec flat-top receiver. Machined from billet 7075-T6, the Stealth is designed with more of material in critical areas to alleviate past issues of weakness and to stiffen the receiver, maximizing the weapons overall accuracy.”

Geissele MK4.

Rainier Arms Ultramatch Barrel.

I’d build it around these parts. No point carrying the length and weight of the traditional SPR.

Nope they are out there, just $$$

I was offered a Army Recon version for $1800, and just couldnt pull the trigger. Love the optic, but thats way over what I consider it’s value. Could pick up a Razor HD for that kind of money.

No, the ultramatch is anything but. Many guys have built on them , and they are nothing special. Many have gone back to Rainer.

As far as barrles go, nothing will even come close to WOA for value. They simply shoot, and the price cannot be beat. Ive built SPR’s withLija’s, CLE-Kriegers, Noveske’s, and WOA, and to be honest, WOA did not lose a step. I did get a little more fps out of the Noveske, and the intermediate gas system is a little smoother, but not $350 better.

You need to decide if you want to build a clone, or a SPR type rifle.

Mod 0 and 1’s will be expensive to build. They use ARMS parts, which I refuse to put on any rifle I own. The PRI rail is expesnive, heavy and dated. To be honest, both are very dated designs, and much better products that are lighter are on the market now.

If I was buiding a SPR type rifle, I would go with a WOA SPR barrel, Fortis 14" rail/ Geiselle/URX , Geiselle DMR/SSA, and a SOPMOD or Bravo stock. Top it off with either the Vortex 2.5-10x32 or the SS 3-15 (best DMR type scopes under $1500). Both are FFP and mil/mil in a NON qd mount like the Badger 1 piece or KAC 1 piece. QD mounts have no place on precision rifles. Throw an atlas bipod with either ADM or Larue QD and quality brake/comp …now your talking.

This will result in a light, very high quality rifle for the money, that will shoot as good as you and the ammo you feed it.

The more I research over the past few days. Def not going to be a clone. Why pay for outdated parts (some are like you said) when one can get nicer/high quality parts. This is going ot be a SPR “concept”

Lower will be for the moment my DD. Then Barnes/BCM/DD/OTT (other top teir) Etc.
LPK DD/BCM/Barnes
Rainer Rapter Charging handle (I’m a lefty)
Troy ambi mag release
Bad-ass ambi safety
BCM grip
DD/BCM BCG
WOA SPR SS rifle (will cerakote/other paint effect accuracy?
Looking at Troy Aplah rail (something 13 inches that is light but tough)
Low pro-gas blockBCM/DD/ OTT

As for gas system toss up between a mid and rifle. If I use a rifle can I use a carbine spring? Reason I ask was I read that some Magpul stocks don’t accept rifle springs and buffers and only carbine.

If you want light, than Fortis. It is also very economical.

The gas system is rifle, not the tube. You can use a carbine tube with a rifle or intermediate system. I would stay away from magpul stocks not named PRS. SOPMOD/Bravo is a much better stock than magpull’s lineup and lends itself to precision shooting, while not being huge or too heavy. Add https://www.rainierarms.com/?page=shop/detail&product_id=3656 and then you are cooking with gasoline.

I could be wrong, but I think Centurion has always been top notch for an SPR clone.

Personally I went with a Noveske 18" barrel for my build, but my rifle only shares the rudimentary/basic formula with the real SPR [bbl length, free float hg, match trigger, NF 2.5-10]. The Centurion, PRI and High Caliber seem to be as close to a clone as one could get… I think…

I have an empty A2 lower sitting around and have been looking to get a true Mk12 Mod0 clone. But the inability to have the OPS 12th Model brake/collar in NJ already shoots the “clone” idea to shit.

None of those are “top Teir” barrel makers with the exception of maybe Noveske, when he used to use Lija Blanks for his barrels (no idea now).

Read the PRI article, and get a chuckle. They talk about the biggest mistake made on the MK12, was going away from PRI. What a bunch of narrasistic bullshit. Its been 10 years and PRI still hasnt made anything new…they seem to follow ARMS business model.

A precision AR always starts with the barrel. You should build the gun around that.

The REAL SPR also did not use the Nightforce untill later into its life cycle. They used Leupy 3.5-10’s. The current 2.5-10x32 is a good optic, but not $1500 good. The Vortex and SS 3-15 are 99% of that optic at 50% of the price. They also used the Origional KAC 2 stage, which was generally considered a piece of shit and unreliable. Thats how Giessele broke into the military market. He was making his Hi Speed trigger for High power shooters, and then designed the DMR for the MK12/MK11 as guys were replacing the KAC 2S with it. Whatever KAC did to their trigger design however, the Newer KAC 2 Stage is the SHIT. It is every bit as good as any Geiselle triggers I have shot/owned.

Thanks Turrent Gunner for the info!

Do you have any idea how many people use ADM, Larue, GDI, Bobro QD mounts on precision rifles? I’m guessing not.

Have you ever shot the SOPMOD/Bravo from prone position in a precision capacity? I guessing if so, not much at all.

It’s one of the worst stocks, or most difficult one to master in prone position as you continually find yourself hitting the adjustment lever if your properly using your hand in the rear.

The UBR is one of the finest precision stocks made for the AR FOW. The ACS, and STR models have a nice toe on them, and protected levers that make them much more ideal for prone shooting…i.e. a precision rifle’s primary position.

You can’t be serious saying a Vortex/SS is 99% of a NXSc. That’s just crazy!

I can say being 25 yr. My pockets do not go deep enough for a NX…I had planned on a vortex in the 700-800 market probably. May not be AS good as NX but good enough for me. I appreciate all the help in this.

Trident,

Ive owned them ALL with the exception of GDI. I stand by my statement, They will all exibit POI shift…some more than others. I have found Bobro to have the Least, and from people I respect, they claim that GDI is also on par with Bobro. With that being said, I still don’t run QD on any precision rigs. Badger 1 peice or KAC 1 Piece. We can debate the merits and designs of each QD, but thats for another thread. Anyone serious about LR and precision does not use a QD mount, unless they HAVE to. Acogs, 1-4/6x, Elcans and RDS aren’t precision.

I have also run the SOPMOD for the last 10 years on just about all of my AR’s. They are on my MK12, .308 AR’s and on my KAC guns. I find it to give the best cheek weld and the most comfortable outside of the PRS (which is a pig). It has a nice flat surface that can be built up if need be and plenty of surface area to work with.

Please explain to me how the Vortex is so inferior to the NXS? Ill give nightforce has a better zero stop and argueably a slight edge in the reliability/durrability department. The Glass in the Vortex is AS good if not better than NF and the MIL reticle is IMO, a better one than the 10 or whatever NF offers. It also has the best, no questions asked warranty in the optics world. NF will dick around with warrantee work, Vortex will have you a replacement by the end of the week.
Have you even shot the 2.5-10x32 Vortex? Its one hell of an optic. Also, who the hell wants a SFP scope in a precision/dmr/sniper role? That ship sailed 10 years ago. The 2.5-10x24 was one hell of a scope for it’s size, but like idiots, NF decided to pull that from consumer market. They can go **** themselves with their overpriced, old technolgy. Their old prices were a good value, Now there is better for less (Bushnell HDMR/G2DMR, New Leupy, Razor HD, SWFA 5-20,ect) For the price of a F1 or their latest offering I can get a Khales or S&B…its not even a choice.

Quote from Centurian arms Mk12 barrel page;

These barrels come from the same machines and the same people who make the military MK12 barrels for the Special Operations community.

taken w/ a grain of salt, but I see no gain in it for Monte to lie. Or LAV for that matter.

High Caliber Sales advertise the use of Douglas barrels.

PRI might have a lot of self serving BS in the article, but they advertises the use of Douglas barrels as well.

They all could be full of poop, but if they are not, the barrels are G2G.

Like I said, my SPR-ish rifle is built around a Noveske barrel, but I would have no reservations in using Centurian or the Douglas barrels that PRI and HCS claim to be using.

The NF 2.5-10 is an awesome optic, I have no complaints.

There is nothing wrong with a Douglas or Noveskee barrel. They are good shooters. But they are not Kriegers, Bartlien, ect. There is a reason those tubes sell for $$$ and guys who shoot LR use them . For a mK12 shooting blue box 75/77GR, I don’t think you will notice much of a difference.

The Mod 0/1’s also used ARMS #22 rings, does that mean they are the best product for that rifle? The same can be argued for any componet. Unless your building a clone, there is no reason to not use better parts, and that includes the barrel. WOA is every bit the shooter that the Douglas or CLE is, at half the price. It is also already profiled for the Ops inc brake, if you go down that rabbit hole.

Which 2.5-10 are u talking about? There are 3, and none of them are FFP. Once you go FFP and Mil/Mil you never go back.