MK12 Rifle - Help Choose a model

[TheGunGeek]

I've decided my next purchase will be a 5.56 MK12 variant marksman rifle. It will only be used with Black Hills 77gr OTM or TMK. The focus will be on long range accuracy and reliability. I've researched what's available and determined the following so far:

I like the Bravo Company offering, but it's only offered in the 1/8 twist so I've ruled it out, as I want the best long range performance.

I'm currently between the Wilson Combat SPR and building my own using a Centurion upper. The plus for the Wilson is the custom color options, and their reputation for quality and accuracy. The plus for the Centurion is the authenticate specs, and the potential to add the Allen Engineering suppressor.

Are there any other options you recommend? Between the two which do you think is the best way to go?

[Bartholomew Roberts]

Call MSTN and have them build you one. They are about as close as you can get to a retail version of NSWC Crane.

Having said that, the SPR is pretty old-school tech these days. You could improve on it a dozen different ways. MSTN can do that as well.

[JeepHammer]

Crane is just up the highway from me, pretty interesting stuff comes out of Crane once in a while.

I have to point out that .223/5.56 wasn't ever intended to be a long range round.
While you *CAN* stroke a .223 to reach long range, it's much more practical to go with a slightly larger/heavier round.
Several rifles off the shelf will do as well as stroked .223, often more consistantly.

One thing I can tell you is the mk12 ammo isn't available.
The ammo & barrel were developed together, powder is proprietary and a closely guarded secret.
The rounds aren't even made at Lake City, as far as I can tell they are General Dynamics loaded.

[Bartholomew Roberts]

Jeephammer, Black Hills loaded the original Mk262 Mod 0 77gr ammo for the military using a Sierra bullet and they load the later Mk262 Mod 1 ammo as well. Both were available for retail sales to civilians. (You’ll only find Mod 1 available now).

Mk262 is a bit faster. If you back off the velocity a bit (say, Black Hills .223 77gr) you’ll get slightly better accuracy.

Edited to add link.

[TheGunGeek]

Originally Posted by Bartholomew Roberts

Having said that, the SPR is pretty old-school tech these days. You could improve on it a dozen different ways. MSTN can do that as well.

Agreed, I'm not necessarily looking for a replica, but the accuracy. The Knights Armament SR-15 in the 18" barrel looks interesting also.
https://www.knightarmco.com/12013/sh...pr-mod-2-m-lok

This would complete the 5.56 set planned for the household, so I was thinking of a DMR to round out the group, and for ammo and magazine commonality. I suppose I could just skip this and go to an A10 variant, however the commonality is then lost.

[Bartholomew Roberts]

The Knight’s doesn’t disappoint, then again not much in the price range you are looking at does. I have an MSTN built Recce (my version but with the original barrel they used) and it is still a laser even with about 6,000 rounds down the tube. The Knights SR15 has a lot of proprietary parts but it runs great.

[jugornot]

You probably aren't interested but for a long range AR, I have a Rock River Arms Varmint with a 24" stainless barrel 1 in 7 twist that approaches 1/2" groups at 100 yards. I am old and somewhat disabled and could not imagine carrying this any long distance. I reload 77 grain SMK and STMK that over the life of the gun average .6" groups. That is average. The best it has ever shot is .39". It has a nightforce benchrest scope. I am satisfied with it but will always strive for better. The only mods are prs stock, a platform grip and a DLC BCG. It is truly a joy to shoot, but not to carry. I would not hesitate to use it for varmint.

[JeepHammer]

When the weather is just right, I shoot a 24" varmint barrel (prairie dogs/ground hogs) and my home 600 yd target. Keeps slightly over 1/2 MOA with exactly the right hand load.
Slightly under 1 MOA with my standard hand load varmint round.
Nothing really special with the exception of the barrel, hand fitting of parts on assembly.

I've not found, or seen, a .223 that shoots reliably much past 600 yds from anyone, with any load, for any amount of money.
I've seen guys try to shoot 1,000 yds with .223, and it always depends on altitude & weather conditions, while even the off the shelf .308 guys were killing it.

The other point to make is, *IF* you decide to jump off the AR-15 platform to say AR-10, then there is no reason to stick to a .308
There are lots of calibers based on .308 that will cycle & function fine through the AR-10 platform.
My favorite was a .300 Win Short Mag. Fewer rounds in mag, but functioned fine & shot great.

It's not an AR-10, but the AR style has been applied to a .338 Lupua Mag round, got a chance to see one in action a couple summers ago and it was impressive.

I guess if you just had to stick to AR-15 format, then I might mess with trying to shoot long range, but the cost & trouble goes up exponentally, and considering the .338 LM is an honest 2,000 yard round, that pretty much redefines 'Long Range'...

Since the OP never defined what he thought 'Long Range' was, or even what he was wanting to shoot, I kind of had to cover all the bases...

[Bartholomew Roberts]

I'd agree with Jeephammer that 600yds is the practical maximum for most shooters with 5.56x45. There are a few who can push it further; but even with the best shooters, you are probably looking at 800yds max.

With the budget you are discussing, you could have a Ti AR10 built in something like 6.5 Creedmoor that would be as light and accurate as a Mk12; but have considerably better hitting power and a 1,000yd practical range. Of course, you will sacrifice ammo cost somewhat (though not much if you plan on shooting Black Hills 77gr exclusively) and recoil will be a tiny bit harsher.

You also mentioned ammo commonality was important to you, so that wouldn't help there either.

[JeepHammer]

There is only one reason to have exclusively the .223 version of AR-15, and that's you have a self imposed .223 limit.
In that case there are BOLT RIFLES that would be more accurate at relative ranges for the .223

A 'Collector' would exclusively 'Collect' AR-15 format rifles.
Since AR-15 has come in every caliber from .17HMR to .50 BW, the ammo wouldn't matter.
This isn't a 'Collection', this is an accumulation of random AR format firearms with little or no collector value.

For instance, an actual 'Collector' would specialize in Colt, or some other maker.
There is increased value when you have every model of Colt AR-15 over piece value of single rifles.
Everyone in the gun manufacturing world has cranked out an AR, and they all changed something so interchangeability of parts is out the window.
The sheer volume of ARs produced precludes any actual overall 'Collection', while some are so poorly made I'd be embarrassed to own some of them.
Again, zero collector value.

The third group is 'Survivalists'... EOTWAWKI... SHTF... (Whatever...)
While you can preach 'Weapons Systems' until you are blue in the face, they never quite catch on.
Always a pile of different makers, different parts, different stock & barrel lengths thrown behind a door or stacked up in a corner somewhere.
Zero effort or IQ points applied to standardized ammo, parts interchangeability between the different makers, a pile of random magazines...

I process about 500,000 brass (5.56mm) every month, all standardized, and when I load I have a standard load that every 'Stock' rifle I own is tuned to accept and shoot at maximum capability.
I started with GOOD AMMO, then built good rifles around that ammo...

I was wondering about this when the OP said something about he wouldn't consider a 1:8" twist barrel...
While the gun rags try and tell you a 1:7" or 1:6" is 'More Accurate' it simply isn't true.
.223 started with a 1:16" twist for small varmints. This is the varmint load & barrel twist rate that got the .223 round it's 'Inherently Accurate' status.
Keep in mind, that was 30-45 grain bullets.

As idiots decided to increase weight of the bullet, shorten the barrel all while trying to maintain velocity, that's when twist rates increased, to stablize ever heavier bullets out of increasingly short barrels.
This was never intended to be a deer or human size animal killer, and it's marginal in that role currently.
(Ask any combat troop that saw a bad guy take half dozen rounds & still keep shooting)

A tuned rifle with a reasonable load is more important than the super duper barrel twist.
A reasonable caliber for the game you are hunting is more important than 'Tacti-Cool'.

To be quite frank, barrel break in & bolt fitment to the chamber is more important than the barrel twist rates.
When you use a quality bullet, one that isn't off center, out of round, has the correct BC you don't have to overspin the bullet to be accurate!
Overspinning is a good way to maximize lousy bullets, inconsistent velocities, but it's not going to help a poorly built rifle very much.
Off center, out of round and out of square will always show up in the function of the rifle, and with gas operated semi-autos, not tuning the gas system is going to cause big problems.
There is a reason so few .223 shooters reach out 800 to 1,000 yards, and why so many novices fail at 300 to 500 yards...
You can't expect a $300 farm store special to shoot with a properly built $10,000 competition queen.
There is also a reason the guys that reach 800-1,000 yards are gunsmiths along with being shooters.
The more you tune, the better you shoot, and that means you MUST know how the rifle is working, and be able to correct it's shortcomings.

No matter what you pay that 'Long Range' shot isn't guaranteed!

[Bartholomew Roberts]

Happy St. Patrick's Day, JeepHammer!

[TheGunGeek]

Originally Posted by JeepHammer

The other point to make is, *IF* you decide to jump off the AR-15 platform to say AR-10, then there is no reason to stick to a .308
There are lots of calibers based on .308 that will cycle & function fine through the AR-10 platform.

For the AR-10 platform, I was planning on going to a 6.5 Creedmore which "should" provide consistency in the semi-auto platform out to 1,000 meters.

For the 5.56 DMR, I'm considering long range at 400 - 800. I know people have taken it to 1,000 with Black Hills TMK, but I think that's really stretching it too far.

Even if I get the DMR, the planned collection still includes adding a Desert Tech bolt action gun with .338 Lapua Mag & 6.5 Creedmore conversions. With this range of rifles, I should have all possible uses covered. If I eliminated the DMR I would just shift the purchase to the AR-10.

I should mention all my semi-auto rifles are more modern piston versions, so I figure I really should add add an AR-15 of some kind.
I saw Precision Reflex has the MK-12 mod 0 with the Douglas barrel and a sub-moa guarantee. At the same time, it would be nice to have something in the safe with a sense of history. What do you think?
https://www.precisionreflex.com/Deta...64491&CAT=8619

[TheGunGeek]

Originally Posted by JeepHammer

I process about 500,000 brass (5.56mm) every month, all standardized, and when I load I have a standard load that every 'Stock' rifle I own is tuned to accept and shoot at maximum capability.
I started with GOOD AMMO, then built good rifles around that ammo...

I was wondering about this when the OP said something about he wouldn't consider a 1:8" twist barrel...

First thank you for the very detailed post, with lots of good information. I try to standardize ammo within the calibers (and minimize calibers) as much as possible to keep things simple. All my other 5.56 rifles have a 1/7 twist, and I primarily stock Black Hills OTM & TMK. I believe we are both on the same page with this.

I'm not a serious collector nor a survivalist , just an enthusiast and Liberty minded individual who believes that practical accuracy is a civic responsibility.

[TheGunGeek]

Originally Posted by Bartholomew Roberts

Happy St. Patrick's Day, JeepHammer!

And yes, have a happy green beer day!

[JeepHammer]

16 years in the Marines, I know 'Liberty' and firearms have little to nothing to do with each other.

I usually tell people to stick with fairly modern military calibers, either NATO or Warsaw Pact.
The WORST US made military ammo (surplus) is light years above Warsaw Pact ammo, so sticking with current US military ammo lowers price and gives inherent quality.

I lean away from calibers that are discontinued, .30-06 for example, but I don't write them off entirely since the brass is cheap, every civilian manufacturer makes it, and it's still quite effective.
Not so much with .30 carbine or .30-40 Kreg

I lean away from .338 LM because it's expensive, and there is no such thing as surplus, even cases are hard to find.
There is also the fact I'm aging, between eyesight & arthritis I can't shoot 1,500 or 2,000 yards anymore, even if the rifle & ammo are capable.

People that have never shot a Boomer at 1,000+ yds *Thinks* they 'Need' a semi-auto, while I've seen hundreds of bolt shooters put lead on target just as fast as the semi-autos.
Stright pull bolt rifles are particularly fast, I watched a COBB rifle shooter just kick the crap out of a Barrett shooter on the range.
It's the time back on target and corrections that take time, boomers don't stay on target in the field, and you rarely have a pile of sandbags handy...

As for AR-15 rifles in bulk, interchangeability & spare parts MUST fit! Period.
The 'Standard' should be as close to military production as possible simply for the quality of the parts.
Military minimums, you can improve for application (optics, stocks, supressors, etc)
Patrol rifles get the crap knocked out of them and things do break, fail to function, just plain wear out...

*IF* you decide to break off into AR-10 style rifles, be aware there isn't a US standard.
Uppers, lowers & BCGs don't play well with each other, and even things as simple as gas tubes are often proprietary.
When someone is wanting more than one, I usually steer them towards the same maker so most parts interchange.
Since you can't shoot more than one rifle at a time, you might keep more than one upper/caliber (complete) and the correct buffer & spring for that upper.
Short stroke gas pistons won't save you on the buffer/spring issues when you make a big jump in power.
I have .308 Win and .300 WSM uppers for the same lower simply because I have the lower set up with the stock & trigger I like, swapping takes 30 seconds.

People make fun of those that use surplus military parts, I don't.
The crap sold as 'Military Grade' is usually a long way from it...
A military National Match barrel is every bit as accurate as a 'Varmint' barrel, but doesn't have exposed crowns & other issues.
Off a bench I've often fired 10 shot groups through National Match barrels that you can cover with a dime or nickel, and that's pretty good shooting in anyone's book.

[TheGunGeek]

Good morning,

So you've convinced me to drop the 5.56 DMR and move up a to a heavier caliber. I also agree that a bolt action is more accurate and can be run quickly given the training and practice. One of the intermediate length courses I plan to run is challenging to do with a bolt rifle given the time constraints, however it can be and I've seen it done. I did however pick up an Wilson Ar-15 lower over the weekend as a "project" gun, so I can always put a precision upper on it down the road if desired.

I really do enjoy the precision side of the sport, specifically practical precision, where you have to be very accurate from different positions, but you're also under a tight clock which really tests your fundamentals.

I'm going to pick up an AR-10 and then the bolt rifle so I have both to work with. Thank you again for all the guidance, I'll post a pick once I have it in hand.

Best,

TGG

[CrazyJoe81]

TGG Don't give up on the MK12 yet. I have one from High Caliber Sales (builder is retired from NSWG Crane). Upper is Bravo Company, Douglas BBL 1:7, etc. I bought the upper and OPS Inc. (now Allen Engineering) from Kevin at HCS in 2010. http://highcalibersales.com/ for the details. Not a nicer guy in the business. He also stocks BH 77gr in bulk. Its all I shoot. Its still my favorite 5.56.

[JeepHammer]

I live about 30 miles from Crane.
Crane contractors are most of my machine shop income.

What you guys don't seem to understand is, the Military 'Long Range' 5.56 rifles shoot a specific ammunition.
That ammo is proprietary to General Dynamics and isn't available to the public, so referencing a specific WEAPONS SYSTEM that only the military has access to the ammo makes for a moot point...

The ammo had to have a greatly reduced enviornmental signature (muzzle flash in particular), it has increased velocity without increasing chamber pressures (in the event it's mixed in with standard ammo doesn't blow up the standard rifles), and it has a couple other requirements...

The ammo is made by General Dynamics, not the usual military ammunition plants.

GD is NOT letting the cat out of the bag yet, so it's 'Un-Obtainium' to civilians. It actually takes a security clearance to handle the loaded cartridges, I've only seen half a dozen boxes and not been allowed to handle them.

SO...
If you want to re-produce the Mk12, you will have to come up with a round that matches the GD rounds from civilian components.

Again, I point out money spent on a firearm you CAN NOT aquire the proper ammunition for to reproduce military ballistics isn't money well spent...

Yes, the designated marksmen practice with common ammo or black hills ammo, the hard core SF uses the proprietary ammunition, as it should be with SEALS, etc., Guys with the skills to put the system to it's MAXIMUM use.

In this circumstance, it makes a LOT MORE SENSE to get a 'Varmint' rifle, shoot a good quality round (or build one if you reload), and sharpen your SKILLS before investing in some 'Uber Rifle' intended for a completely different application...
$1,500 to $2,000 for the upper only is a serious chunk of money, particularly since it will never be deployed for the mission it was designed...

[CrazyJoe81]

Oh I understand alright.

TGG If you STILL want a MK12 after all that I applaud your choice. I didn't want a varmint rifle either.

[CrazyJoe81]

This may be interesting.

http://www.shootingtimes.com/ammo/sp...-mod-1-review/

YMMV

[TheGunGeek]

Originally Posted by CrazyJoe81

Oh I understand alright.

TGG If you STILL want a MK12 after all that I applaud your choice. I didn't want a varmint rifle either.

I'm still planning on adding a MK12 variant at some point as a medium range DMR. If you're going to have only 1 AR-15, it should be interesting. I'll either pick up a PRI complete rifle or an upper that I'll add to my custom lower.

That said, I'm prioritizing my next addition to a 6.5 Creedmore caliber. This will better serve the gap in my current set-up, and is a wiser addition at this time for long range.

[freq18hz]

OP:

Have you looked at PRI? They took over the contract for a time for the mk12.

They ship to spec, with the Douglas precision barrel, the correct brake etc.

I own other highly accurate 18 inch ar’s including a knights sr-15 LPR with a krieger barrel.

The MK12 outshines them all, and consistently shoots under half moa with black hills 77 grain OTM (contract provider for the mk262 round).

They are large and unwieldy, but if you want an accurized 18 ar, you won’t find a better one off the shelf.

-Freq