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MK 12 Picture & Discussion Thread
- Thread starter OzzyO20
- Start date
Been running AAC 77 SMK and their in-house OTM projectile loads lately (with a local store to buy from). Couple of groups from the last outing at 100yds.
Snagged an H&R M16A1 lower last year from the first batch to repurpose the Nodak A1 lower it had...love the grey so left it as is and didnt repaint. White Oak SPR barrel. A5 receiver extension and A5-H1 buffer. Geissele BCG and SD-C. An old Battleline Industries SAPR attachment for the stock. Put the Vortex 1-10 (NF Unimount) back on it again but need to pick up a higher mag NF. Every time I shoot this I come back to wanting more mag.
Snagged an H&R M16A1 lower last year from the first batch to repurpose the Nodak A1 lower it had...love the grey so left it as is and didnt repaint. White Oak SPR barrel. A5 receiver extension and A5-H1 buffer. Geissele BCG and SD-C. An old Battleline Industries SAPR attachment for the stock. Put the Vortex 1-10 (NF Unimount) back on it again but need to pick up a higher mag NF. Every time I shoot this I come back to wanting more mag.
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MK 12 Mod H in 6 ARC - 16" Proof. .5MOA groups with factory 108 ELDM and will ring steel all day at 1,000 YD... transonic around 1,050 YD.
Yes the gas block sticks out of the hand-guard and you can't run the nostalgic OPS INC clone cans, but the increased performance more than makes up for it.
Yes the gas block sticks out of the hand-guard and you can't run the nostalgic OPS INC clone cans, but the increased performance more than makes up for it.
Not really a Mk12 then is it
It's just a AR with a PRI rail....
It's a nice rifle tho.
And you can have the Ops Inc/AEM5 can bored out to 6mm. There are several people who have done it.
It's a nice rifle tho.
And you can have the Ops Inc/AEM5 can bored out to 6mm. There are several people who have done it.
It's a Mk 12 Mod H to me. The can does not make it or break it for me.
Yes, the AE can and barrel setup is the heart of the mk12
Finally got mine done. Ordered the KMW pod loc this morning. Decided to go with the 3.6-18 like @5RWill did. After I shoot it I will finish up the Krylon
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This.
Looks great!
Speaking of 6Arc mentioned above. While the energy on target is certainly greater I was pretty surprised by one of members head to head with 14.5" 5.56 vs 6arc. It's not nearly as unevenly matched as you'd think it would be.
A good friend of mine was going to do a Mod H in 6arc with a bored out AEM5 or OCM5. He did recently pick up an OCM5. But when we got to thinking about it he basically said "until I can reliably pick up 6arc locally it's not a replacement." I'm getting that way the older I get. Don't get me wrong I have niche wildcats like my 7 Sherman Short, but I've long sold off the 6.5 grendel and 300blk I had cause ammo just isn't that readily available for similar price. And it's somehwat predisposed to gassers because I tend to lose brass and shoot more volume with them. But if one were to build say a 6arc in a bolt rifle it doesn't make any sense to me.
Meanwhile I'm still loading but as of late even in this climate I've found 300PRC for $1.72 a round (Hornady 225gr), 308 match (norma 175gr) for $1.56 a round, and 77gr OTM at .65c a round through AAC. Hell I'm going to probably pick up 100rds of 70gr TSX AAC stuff for the MK12 for deer season just to use it to take some doe.
Within the constraints of an AR mag no new cartridge will be in a vastly different league than the last. Improvements are pretty incremental. I've tried most of the longer range capable cartridges that fit in a AR and I'm still back at 5.56 most of the time. I've got a 6mm Grendel and the performance is better, but not incredibly so. If I was guessing, any long range shot I miss with a 5.56 there's at least a 90% chance I'll miss it with the 6mm. So the onus is still on me, the cartridge increases my odds very little.
I think I commented something to that effect on your 5.56 vs. 308 video before I watched it, but in fewer words.
Edit to piggyback onto what @LRRPF52 says below, impact signature is greatly increased going from my 5.56 to my 6mm and then again going to my 6.5G. When I say the performance isn't drastically improved I'm only speaking in terms of hit percentage, not energy on target or hunting use.
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Even when I’m ROing at a match for guys with 6 Dasher, 6x47, 6CM, .243 Win, etc. in a much larger case, it becomes really hard to hear the impacts once you start getting out from 600-700yds, depending on wind speed and direction. 7-10mph full value and the 6s sound really anemic, and even small plates barely move, which is hard to see in atmospheric shimmering. Spalling mass is often not enough to see the splash at the TGT base as well.
123gr 6.5 from Grendel sounds more like a .308 impact, not fully at 175gr SMK level, but somewhere like a 155-168gr. I can see and hear them better on-steel at distance. 130gr 6.5mm even better. It’s a little easier to connect with 6mm AR or 6mm BR variants, but not as much momentum on the steel.
.223 Rem even hot-loaded from a 22-24” bolt gun is just anemic at distance, no matter what you do. Still fun to shoot and watch the reticle not move, but it doesn’t give me that positive loop feedback audible return I like to hear so much. At my last course, there just happened to be an unintended sim shot on a 12” steel at 760yds between a 22” .223 Rem bolt gun spitting 77 SMK fast, and a 12” Grendel with 123gr ELD-M. The 77gr hit with a tiny little “tink” and barely-perceptible nick on the paint, while the 6.5 hit with a solid “whack”, with clearly-visible large spalling impact. If you put that on video, it would really illustrate the difference.
I can duplicate the weaker impact sound of 6mm AR/6mm ARC from Grendel by stepping down to 107gr SMK and the 110gr PPU factory ammo. Very flat trajectory, easy to hit, great for the kids to practice with, but isn’t anywhere as loud as 120gr and up. Sounds exactly like a 105-108gr 6mm impact, weak and faint, hard to hear.
Mk.12s deserve 6.5mm if you like to hear the impacts on steel past 300yds and live in a windy area, and also want to hunt more game size with them. If you just want a clone and like to shoot it at ranges that don’t have a lot of distance, it will punch the steel pretty hard at 200-300yds, but so will short barrel 5.56 carbines. It’s a great rifle to learn on due to how pleasant they shoot suppressed, no sight picture disturbance really.
I’ve had a lot of them come through DM courses, as well as a ton of 16” guns with good ammo (Mk.262, 75gr Hornady, 69gr SMK, etc.) and it becomes hard to see and hear registers on steel once you start going from 400yds on-out. Reviewing target cam footage can confirmation-bias away from the actual shooter/spotter experience, since you’ll never hear the impacts that loud until later when watching what happened.
With Grendel, you just know immediately whether you hit or not due to the projectile mass of the 120gr and larger loads. That’s one of the fundamental things with Grendel that often is overlooked that makes me enjoy shooting it so much.
In practice, I’ve pretty much relegated 5.56 to CQM-300yds, occasionally 400-500yds just for giggles.
I noticed that as well between 5.56 and 6mm AR, although 6mm AR will genuinely reach out with good hit probability at distance and not suffer as much wind drift. The impacts aren’t like a .308, which is what I want, but without the large frame, recoil, muzzle blast, big mags, loss of sight picture, etc.
If someone could make a 195gr 7mm EOL exit at 2850fps and recoil like a .223 Rem 40gr, I’d be all over that. I also want Marylin Monroe to come back as a virgin without her Hollywood mental issues.
Yeah I edited my post above to mention that hit signature is greatly increased as you step up to 6mm and then 6.5mm.
I was actually thinking the same thing yesterday. Wonder if somebody is going to make the proper profiled barrel
Wonder if you could take a reamer to the 223 barrel? Idk how that would work with the extension and feed ramps but if it’s possible. I mean mk12 slinging 88gr ELD at 2800 is an entirely different animal and makes so much sense in my head to keep it separate from my 14.5” with an LVPO.
However ammo availability will be the issue. But if aac makes ammo for it at reasonable price and their QC improves it would be awesome.
Heads up for anyone planning on or interested in the Mk12 Mod H: https://supdef.com/noveske-mk12-mod-h-barrel-16/ Noveske originally made the contract barrels and this is a limited run of 100 made to that print. It is the only "clone correct" barrel for the build.
I really didnt have good luck with AAC ammo out of my Mod H. I tried their 69 grain, 75 and 77 grain, best group I got was with the 77 grain. Going to try some Gorilla 77 grain next and then I will do a load development.
I have an 18" that I had listed to sell, going to see if I can find somebody to ream it to 22 ARC
22ARC shoulder is further back, so you'd have to set the barrel back to get the reamer into fresh steel. In an AR that means re timing the barrel extension to the gas port while keeping heaspace in mind. Technically doable, but good luck finding a smith that wants to.
Thought it might be a lot of work. Might have to just piece together another mod H upper. Doubt i could sell my barrel
Rattle Can is best Can for my now complete Mod 0 now that I have a correct Loopy Mk4 on there.
Mod H. Got rid of the RAID-Xe, I've been through several dozen of lasers and always go back to ol' faithful LA-5B or an NGAL. OCM5 still waiting in jail.
Using this with the CNVD-LR is a bit of meme, need to be at 8X to really make use of it and at that point, it's what the SR25 is for in a way with a 4-20 ATACR.
(Also put this same pic on reddit and got one particular poor very upset in my messages about it, apparently spending too much money is bad)
This highlights one of the most important things about the SPRs that some of the original 1992-1994 JSOC Sniper Carbines had to use SIMRADs to achieve due to the presence of the Front Sight Base.
Most cloners don’t think about the emphasis on how the units using these things prefer to work at night.
In my last DM course, we were double-tapping targets at 700yds with 6x NV even with 5.56. I got bored doing it prone and went to kneeling just to show it could be done.
But I don’t get excited much about 5.56 in these types of set-ups.
One could almost argue cloners don't think about the emphasis on overall usage, either lol.
It's more of a personal design philosophy of mine, I was only a tech back in the day supporting coolguy units and could mostly learn OJT or by osmosis the method to the madness, but more broadly I've compressed my firearms down to "use what at X range" and make sure they're all capable of 24x7 fighting - be it piggybacked dots to use passively or having the space + quality optic to use with a CNVD or clip on thermal.
It's hard to get super jazzed about 556 when you've got an accurate 308 gasser for sure. It's almost boring, I have a E2 PR on a tripod with the CNVD and a NGAL on a diving board and it's pretty close to cheating without a WMLRF/BSC
I think once cloners commit to a can, they pretty much have to get out and shoot it.
Same with optics. You can buy the legacy initial Leupold optics for those prices, but somewhere along the way you’re going to want to get out and do some blasting.
Are you able to stay in the scope with .308 if you turn down magnification? That’s why I don’t shoot the .308s much anymore, even though I have them.
I love the AR-15 receiver set. I love the sound of .308 on-target. I don’t like .308 weight, torque, and loss of sight picture.
Same with optics. You can buy the legacy initial Leupold optics for those prices, but somewhere along the way you’re going to want to get out and do some blasting.
Are you able to stay in the scope with .308 if you turn down magnification? That’s why I don’t shoot the .308s much anymore, even though I have them.
I love the AR-15 receiver set. I love the sound of .308 on-target. I don’t like .308 weight, torque, and loss of sight picture.
SIMRAD was an objective-aligned, prism-based Night Vision optic solution that paired with your day optic before the more modern in-line Clip-Ons were a thing.
Yeah man. I love my rifle setup. I first saw it in 2005 in Hiit, Iraq. One of the ODA guys on a team was cleaning his weapons at this FOB we were at. He had a Mk12 Mod 0 pretty close to my clone. That was my first "damn, nice looking rifle" I saw in the military. I was conventional forces so and the USMC units I was with didn't have DMR's. Only STA platoons had the M40's and other goodies.
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It's amazing how just one part can improve the ergonomics. @TheGerman was kind of surprised I could hit a 50-60% IPSC at 650-730y. Good times.
This! But I’m curious if the AEM5 or OCM5 will work with it though, enough room after the gas block.
Small doe, 400yds on the money. 70gr tsx through and through.
Could you share what rail is on the rifle in the top pic? That is a very nice looking setup.SIMRAD was an objective-aligned, prism-based Night Vision optic solution that paired with your day optic before the more modern in-line Clip-Ons were a thing.
I've gone through a couple of iterations of Mk12 and Mk12-ish rifles starting with a Mod1 built for me by High Caliber Sales. I was able to top it off with a NF mil-spec 2.5-10x32 scope. I built my own version with a Noveske MK12 barrel (brake and collar cut outs and matched bolt). They both shot well but the Noveske barrel was slightly more accurate with BH 77gr.
My current version is a Mod H-ish with a White Oak 16" SPR barrel cut for the Ops Inc brake and collar. I used a Forward Controls Design 12.8" rail which allows room for the Ops Inc collar and proper 12th Model seating.
My current version is a Mod H-ish with a White Oak 16" SPR barrel cut for the Ops Inc brake and collar. I used a Forward Controls Design 12.8" rail which allows room for the Ops Inc collar and proper 12th Model seating.
Not sure. It’s not mine, but another Hide member’s. I just linked some photos showing what the SIMRAD is/was for reference.
I need to get a mk12. everytime I see this thread I get pissed at myself for not having one!
