mk11 vs. mk12 ???

[xtrahta]

What is the difference between the mk11 and the mk 12 SPR? I was trying to find it on google but i didn't get anything... thanks!!

[thatguy96]

The simplest difference is that the Mk 11 Mod 0 is chambered in 7.62x51mm and the Mk 12 Mod 0/1 is chambered in 5.56x45mm. Beyond that there are numerous more technical differences.

[xtrahta]

thanks! :)

[homeinvader]

The Mk11 is made commercially by Knight's Armament based on their SR-25 series, basically an updated version of the 7.62 AR-10. The Mk12 SPR is an accurized M-16 and is/was built in-house by Crane and USAMU and is not a commercial firearm. You can buy the exact same Mk11 that the DoD uses right from KAC including the suppressor, but the SPR is not available as a complete weapon though all the parts used in both the Mod 0 and Mod 1 SPRs are available for building your own.

[thatguy96]

I'm pretty sure that while the Mk 11 Mod 0 was built by KAC it was done so with heavy influence from the people at NSWC, Crane. This seemed to basically be the deal with the XM110 SASS for the US Army. Also, as far as I know the US Army Marksmanship Unit had nothing to do with the Mk 12/SPR program. They were the party that recently built up the SDM-Rs for the US Army, but these rifles are not the same as the Mk 12 Mod 0/1.

[dangerdan87]

"SPR" is trademarked by the Armalite Company.

Thats probably useless info in this thread...but hey...its info.

I'm starting on my Mk12 MOD 0/1 upper right now. I just ordered the full length 18" SPR barrel. I'm not sure what MOD (0 or 1) it will be yet though...

FYI: MOD 0's have the PRI Gen III float forarm tube and the MOD 1's have a 4-railed float rail system.

[homeinvader]

I'm pretty sure that while the Mk 11 Mod 0 was built by KAC it was done so with heavy influence from the people at NSWC, Crane. This seemed to basically be the deal with the XM110 SASS for the US Army. Also, as far as I know the US Army Marksmanship Unit had nothing to do with the Mk 12/SPR program. They were the party that recently built up the SDM-Rs for the US Army, but these rifles are not the same as the Mk 12 Mod 0/1.

Not at all. Mk11 Mod0 was a 100% KAC endeavor, Crane wasn't involved at all. DoD puts out RFPs all the time, KAC just builds something to fit it. That's not to say they didn't take input from the community, but not from Crane. No point as Crane takes their lead from the field operators anyway.

And USAMU was HEAVY in creating the SPR, though most of the R&D work was physically done at Crane. Anything part of or might be part of SOPMOD is, has been and will continue to be developed with USAMU's input. Mark Westrom at Armalite, probably the single most important civilian involved in the whole SPR project, was an Army officer at Aberdeen Proving Grounds and managed Rock Island before Armalite. His Army ties run deep.

[thatguy96]

Look, I've read Wes Grant's written account are ar15.com of how things progressed and at no point does he ever mention the USAMU. Wes Grant got most, if not all of his information from Mark Westrom. I also don't see at all how things relating to SOPMOD, something now firmly under the control of USSOCOM outside of the US Army, means that the USAMU will be automatically involved. If anything the SPR was an outgrowth of Army meddling with Crane's "Recon Rifle" projects, and so I guess that USAMU might have been the guiding force in making the weapon more intermediate instead of following the slightly shorter pattern of the earlier non-standardized weapons that had come out of Crane for the US Navy SEALs.

In fact, if you notice the first mentionings of the Special Purpose Reciever in official literature, the SOPMOD Program Office is already at Crane, and they're the ones leading the development programs. Now, I don't know what your definition of "heavy involvement" but I'm thinking that everyone with a possible stake probably had "heavy involvement" in what would being proposed for 3 additional SOPMOD Blocks that ended up being dropped. SOPMOD Block II developments were simply added to the plethora of development projects that were created to supercede the programs with the further integration of the SF community under USSOCOM, and with the creation of the JSSAMP, which it seems these days is being followed by almost no one.

[dangerdan87]

MK12's are made at "The Ranch".
"The Ranch" is in Ohio...I think...(98% positive)

[TacoDelRio]

thanks! :)

His question has been answered.

[PvtPyle]

If you want one, why not just buy one complete from the factory? We have been getting the Mod ) and Mod 1 uppers for some time now. Just like the military gets except the suppressors. But now we have the Ops Inc cans too....

[dangerdan87]

PvtPyle....who are you? And how do you get the Mk12s?

[homeinvader]

MK12's are made at "The Ranch".
"The Ranch" is in Ohio...I think...(98% positive)

There is no "factory" making SPRs, at least real ones. SPRs were made by a civilian contractor to Crane. For those of you that saw the pilot episode of The Unit, you may have noticed the civilian contractor gunsmith character. That's a dramatized version based on this contractor. SPRs are no longer made, the program is finished with all units delivered. This contractor is awaiting a forthcoming refurbishment program for the existing units.

While the SPR parts are all available, the SPR is far from the sum of its parts. Almost every major component is installed using procedures based on very thorough R&D that captures and retains all available accuracy. Every threaded part is tightened to or close to a target torque and there is a lot of prep work for other parts.

Barrels are Douglas, contoured and heavily post-production worked by another civilian contractor.

A lot of the commercial SPR clones and individual parts are not truly to SPR spec. You see "SPR" barrels advertised all over the place, but they are not really SPR barrels, usually just a straight up 18" stainless steel barrel. While these can be of great quality, the real SPR barrel has a very specific, very unique contour, one designed to fit the OPS Inc barrel collar. Buy an "SPR" advertised barrel and you'll find the OPS inc collar will not fit. A lot of custom builders are doing SPR "clone" builds, but don't really know how to do it correctly. A lucky few know the contractor and have actually watched real SPRs being made, hence they know the tricks used in building them.

[dangerdan87]

There is no "factory" making SPRs, at least real ones. SPRs were made by a civilian contractor to Crane.

Which is at Vince's "Ranch" in South east Ohio



For those of you that saw the pilot episode of The Unit, you may have noticed the civilian contractor gunsmith character. That's a dramatized version based on this contractor.

Hollywood...lol...


SPRs are no longer made, the program is finished with all units delivered. This contractor is awaiting a forthcoming refurbishment program for the existing units.

Or so you think...


While the SPR parts are all available, the SPR is far from the sum of its parts. Almost every major component is installed using procedures based on very thorough R&D that captures and retains all available accuracy. Every threaded part is tightened to or close to a target torque and there is a lot of prep work for other parts.

Barrels are Douglas, contoured and heavily post-production worked by another civilian contractor.


A lot of the commercial SPR clones and individual parts are not truly to SPR spec. You see "SPR" barrels advertised all over the place, but they are not really SPR barrels, usually just a straight up 18" stainless steel barrel.

Term "SPR" in 5.56: A Barrel, usally 18" in length with a rifle length gas port, with a medium contour.


While these can be of great quality, the real SPR barrel has a very specific, very unique contour, one designed to fit the OPS Inc barrel collar. Buy an "SPR" advertised barrel and you'll find the OPS inc collar will not fit.

Mine did....And so did 100's of others


A lot of custom builders are doing SPR "clone" builds, but don't really know how to do it correctly.

I do...


A lucky few know the contractor and have actually watched real SPRs being made, hence they know the tricks used in building them.

Theres really not any tricks....Its like 1, 2, 3...

And here's a little FYI for you, Mk12's dont have a true 5.56 chamber, they have a modified AMU chamber. So an out of the ordinary Douglas SPR barrel, wouldn't be to MK12 spec.

Now...I could keep on and school you about crap that you have no idea what your talking about....since youve never shot a gun before...
I'll put it this way and you've probably heard it before...Just because your young and you think you know everything, YOU DONT

Now go play your little airsoft wars....Cause I'm about to leave for the Kid Rock concert...BACKSTAGE PASSES BABY!!

[PvtPyle]

I buy the Mod 0 uppers straight from the builder and put them on either Rock River or LAR lowers. I then buy the Ops Inc cans from Ops Inc for them. That is the best way to go since they have to be semi lowers for civilian sales. I am pretty sure it is the same contactor since I got their contact info from Crane while I was at a course there.

[dangerdan87]

I need another set of Ops inc 2-port brake ans collar

[homeinvader]

Which is at Vince's "Ranch" in South east Ohio




Hollywood...lol...



Or so you think...



Barrels are Douglas, contoured and heavily post-production worked by another civilian contractor.



Term "SPR" in 5.56: A Barrel, usally 18" in length with a rifle length gas port, with a medium contour.



Mine did....And so did 100's of others



I do...



Theres really not any tricks....Its like 1, 2, 3...

And here's a little FYI for you, Mk12's dont have a true 5.56 chamber, they have a modified AMU chamber. So an out of the ordinary Douglas SPR barrel, wouldn't be to MK12 spec.

Now...I could keep on and school you about crap that you have no idea what your talking about....since youve never shot a gun before...
I'll put it this way and you've probably heard it before...Just because your young and you think you know everything, YOU DONT

Now go play your little airsoft wars....Cause I'm about to leave for the Kid Rock concert...BACKSTAGE PASSES BABY!!

Wow. Not sure where this hostility comes from other than genetic disposition. But whatever.

You are wrong on a few counts, aside from being unstable in general, and you probably have yourself a 2 MOA "SPR" because of it and don't even know it.

SPR barrels have a unique shelf between the muzzle and the FSB and a 20 degree taper aft of that shelf to the FSB flats. That shelf and taper are there to secure the OPS inc collar. If you installed an OPS inc collar without that shelf and taper present, you didn't install it correctly. The presence of the shelf and taper denote a true SPR speced barrel, the absence of it denotes a simple 18" stainless barrel. Yes, it is medium contour, but that denotes weight, barrel diameter aft of the FSB, nothing else. It is much more than a "medium contour" barrel. Do you get most of this from Wilkpedia?

And it's not as easy as 1-2-3 as you say. There are target torques for the barrel and muzzle brake that are not GI spec. It's not slapping parts on like it was an straight up AR.

Enjoy Kid Rock. And I'm sure "backstage pass" also has an entirely different meaning for you too.

[dangerdan87]

homeinvader.....
Would it help you any that I have seen SPR's (real ones) built before my eyes quite a sew times? And unlike you, I am an avid shooter and shoot almost daily and have my own experience in building guns.

And by the way, about the Ops collar on WOA SPR bbls, they do thave the shelf. And the collar WILL NOT go anywhere beyond that leaving about 3.5 cm of barrel showing between the collar end and where the threading stard on the bbl. THe collar just lides on, and is seccured by a single set screw.

[dangerdan87]

Heres my Mk12 MOD 1 I built. And 2 MOA my ass. This haws is getting sub-moa at 600 yards with irons.

http://img.photobucket.com/albums/v37/ermey/Builds/Picture012.jpg
http://img.photobucket.com/albums/v37/ermey/Builds/Picture009.jpg
http://img.photobucket.com/albums/v37/ermey/Builds/Picture007.jpg

Pics suck. Rainy outside.

[Seiran]

*raises hand* Question. What's MoA mean? (I like to shoot, but I don't know all the terms.../embarassed)

[dangerdan87]

MOA = Minute Of Angle

Google it

[Seiran]

Thank you.

And I neglected to mention this last night but, nice rifle. Very nice.

[PvtPyle]

In reviewing the SPR from the current manufacturer, we have decided to take it to the next level and will be building the MK-12 Mod 1. It will use all issued parts except the lower (which as you know the issued lower is select fire) which will be a Rock River with the two stage trigger and standard stock.

We will also offer it with the Ops Inc 12th Model SPR can as part of the package. Because of the effects a suppressor has on the internals, we will offer a chromed bolt carrier as an option.

The barrel will be the issued barrel with a head spaced and matched bolt. The low profile gas block and flip up front and rear sights as well as the bi-pod will be standard, just like the issued piece.

Optics will be those of your choice, but we will offer the issued version of the Leupold installed with heavy steel rings.

Obviously this will be a rather expensive package. We do not yet know how much, but if you are seriously interested email me. These custom built guns will require half down and about six weeks for construction. We will begin the transfer paperwork for the suppressor as soon as your money is down and construction begins.


And for our next trick, we will be building the MK-14 EBR...