Finally finished this damn thing. Took 3+ years to finish it out.
The upper is a Mk12 Mod 1 clone on a Colt receiver with all parts being authentic (to my knowledge) except the barrel. I went with a Noveske 3-groove specialty barrel based off the Mk12 profile (not Noveske’s “SPR barrel”) with a profile for the Ops Inc 12th model can. The Compass Lake Engineering barrel wasn’t available to me at the time and Monty at Centurion was -just- starting out selling his Mk12 uppers and had a huge wait list so I hit an alternative credible vendor (Wes at MSTN). Lower is a Colt 6290 with a Geissele DMR 2-stage trigger, Crane stock, etc.
Waiting for the can sucked because the Ops Inc 12th model can is usually out of stock everywhere. Six months waiting for stock and another six months for paperwork clearance.
The longest torment was US Optic’s SN-3 T-PAL 1.8-10x37mm scope. Normally a USO scope takes anywhere from 3-6 months for a build, depending on workload. However the C2 reticle was a project Kent at C2 Shooting Center was working on with US Optics and I was one of the first “me me me!” guys. So 18 months later, the reticle was cleared for production and I have the first scope with the C2 reticle installed and the new digital rheostat lighting system that replaces US Optic’s 11 position rotary unit. Thing is mounted on set of Seekins Precision rings on a LaRue LT-101 removable offset riser. The reticle is sweet. At 1.8x, you get a “ring” to frame your targets. At 10x, the ring disappears completely for an unobstructed, traditional image. Everything is in MILs, EREK elevation and #3 windage w/stop.
Scope dope (hell, I just got the scope. I’ve had the upper and lower around for a while so I’m more excited about the glass):
Magnifications: (it’s damn hard taking photos through the scope!) 1.8, 6, and 10x
Pose!
I haven’t taken it out yet. I have to read up on the instructions and figure out how to set the damn EREK elevation knob first before I participate in the break-in procedure of, “shoot until dirty. Clean and repeat”.
The glass is clear as heck. The only slight, minimal, smallish gripe is I wish the reticle crosshairs were a tad thinner at the higher magnification range, but it shouldn’t really hinder anything and might make them too think in the medium magnification range since it’s first focal plane. USO first developed a C2 pattern for their 1.5-6x SN-4 first and folks with trigger time and 3-gun testing said it’s a very fast design. Once I get used to it, I should be singing it’s praises.
The AFG seems to present a better angle on my wrist. I like the AFG’s angled surface because without a sling, it presents a nice surface to tuck the rifle towards my shoulder. With a cinched sling, I can push against it to get tension. That’s just my limited experience so far. The only problem I’ve encountered is with bipod onboard, the pod-lock lever can crowd the knuckles if you’re gripping the AFG up front.
The vertical grips don’t feel as good to me because it feels like you’re gripping a stick, while the hand feels more full when gripping the AFG since the palm and fingers are wrapped around that and the rail body. With just rail panels on there, it feels a bit alien to me as it’s 12" of real estate with nothing protruding to act as an index for the support hand. I realize these are personal preferences and not actual technical merit/demerits.
I haven’t tried out one of the stubby vertical grips yet on the Mk12. I did handle a Daniel Defense M4 V1 with the stubby and it felt great, but that rifle is lighter on the front and the location of the stubby grip complemented a 12 o’clock Surefire x300 in front of the FSB so it wasn’t held like a normal vertical grip. It was more like a handstop for indexing the support hand.
I think around $2300-2400. I’d have to dig through my email archives and find the invoice as I was only sent a build sheet with the package itself. The base SN-3 is $1670 on the site. Of course, depending on what you put on it, the price can be much less. Adding reticle lighting, the EREK elevation knob, and a windage knob stop added over $500 to it. I also had a sunshade, caps, and misc. nickel and dime items that added cost. The windage stop isn’t necessary but I feel better with it on there. The EREK isn’t necessary either but it’s one of their signature items and it’s a nice knob.
How’s the eye relief on that set up? It looks like the scope has a huge turret block that makes it somewhat difficult to get the kind of eye relief I prefer on an ar. I shoot almost ntch or else I feel “squished” up and uncomfortable.
Does the collapsing stock help get you further out, or do you shoot in a way that would get a comfortable eye relief.
Not knocking your setup, I had a hard time coming up with a mount/scope set up on my .223 ar that would allow me to be comfortable.
Eye relief is pretty typical. It gets more sensitive as you crank up the magnification but I think that is physics at play. At 1.8x, it’s pretty forgiving. At 10x, it’s about 2-2.5" I estimate and still gives some play room. I think there is enough mounting hardware out there that allows customization to fit most cheekweld preferences. With my particular hardware, I can move it forward to where the rear of the scope is flush with the charging handle. You can get your nose about 2 finger width’s from the charging handle at 10x but that’s it. Any further up and the riser would be hanging in the gap between the receiver and the forearm so a more forward placement on my rig is limited. I don’t happen to position at NTCH and my cheekweld is typically where my cheek just starts to roll off the stock onto the receiver extension with the stock fully extended, about 4" from the charging handle.
A lot of Mk12s are mated with A2 stocked lowers and that’s how I actually started the build because it looked good on paper. I’m a smaller person and it felt great for prone positions but the LOP felt a mile long when offhand. The stock lets me shorten it a bit when offhand which made a huge difference for me in comfort. Unfortunately we’re all slaves to our physiology.
I can see how NTCH would require mounting the scope further out to work. It can be done with tall rings directly off the rail as having it any further up than where I have it now would place one ring over the forearm and one on the receiver. The Mod 0 version used a monolithic rail riser so you could mount optics anywhere on the top. Deviating from the build would allow a monolithic upper or a gapless rail system. Problem with the USO scope is the block that all the knobs are tied to is huge and it won’t work in most single-piece QD scope mounts because the distance between rings is too close. It’s a bit of a red-headed stepchild and it took my bugging a bunch of companies for dimensions to see what would fit.
Murphy seems to sneak up on you when you least suspect it.
I was going to make a trip out today to figure out the EREK knob and zero it in. It’s rare we get a sunny weekend here in WA. Last night I had the rifle leaning against the wall and the dog knocked it over. The rifle slid down the wall and landed right on top of the scope housing. That bent the LaRue riser, but the scope is perfectly fine. Ordered another riser from LaRue and I let them know my situation. Hopefully their warranty comes into play…not sure if that was a fluke since they have a reputation for making tough parts and it wasn’t that big of a spill. Glad to say US Optics is even tougher though because the mount gave up first, not surprising seeing some of the USO torture videos around the web.
Looking for alternatives though, the bent riser has shaken my confidence in the QD riser. I think the bit of rail that sticks out the end is too thin for a scope this heavy. There isn’t much out there by ways of scope mounts for these beasts. Any ideas? Badger makes a 22MOA canted base but it’s not QD so I’d have to get a set of QD rings as well.
Smashing the front of the mount down like that probably turned it into a 30MOA canted base :laugh: Actually I might put the small bubble level underneath the tab of the new riser. It barely fits under there which means if the same accident happened, the rail wouldn’t deform because it wouldn’t flex far enough for the metal to take a permanent set (until I find a better set of alternative hardware)
Man, if some one told me they bent a larue mount I wouldn’t have believed them. However you can’t argue with photos like that. I hope larue takes care of you.
I had never thought about the uso being to big around the turrets to use a one piece mount, that fact really limits options for mounting to the ar.
I picked up a case of Mk262 a few months ago ever since Black Hills started selling it commercially. I’ve been hankering to get more but I’ve saved it for zeroing this scope. Otherwise I’ve been having fun with SSA 5.56 77gr OTM which is similar, but I think a tad less hot.
LaRue has a great reputation for customer service so I’m pretty sure things will get squared away. Here’s to hoping for next weekend!
and the new digital rheostat lighting system that replaces US Optic’s 11 position rotary unit. Thing is mounted on set of Seekins Precision rings on a LaRue LT-101 removable offset riser. The reticle is sweet. At 1.8x, you get a “ring” to frame your targets. At 10x, the ring disappears completely for an unobstructed, traditional image. Everything is in MILs, EREK elevation and #3 windage w/stop.
