Hello all. Long time reader. First time poster. So I am looking to build an ar dmr type build. Was looking to max out at 600-700 yards. So I’ve been a fan of the Hk mr556 upper. I like the build quality and accuracy. However I am a lefty and like a lower with ambi controls built in. In that respect I wanted some outside input. As I have a chance at getting a hk mr556 upper. And was thinking a Daniel defense lower. As the controls are easy to manipulate for my little carnie hands. That or a precision weapons systems ambi lower. Wanted to get input as to compatibility in regards to the buffer system. Has anyone done something similar. Honestly I’m a semi experienced shooter. Have a bunch of ar’s but all direct impingement. Never had a piston gun. So don’t know if my Franken dmr project is viable. Or should I just get the dd mk12 spr upper as well and be done with it. Thanks a bunch. Y’all have a great day.
- Thread starter Jcorvus
- Start date
And my apologies I forgot to mention this dmr I plan to keep it a .223/5.56 platform.
“Little carnie hands” 
I would not pick a piston gun for a DMR rifle. The HK’s and LWRC’s are decently accurate but I had issues with consistentcy with them and also SCARS. Direct impingement is the way to go for accuracy.
I would not pick a piston gun for a DMR rifle. The HK’s and LWRC’s are decently accurate but I had issues with consistentcy with them and also SCARS. Direct impingement is the way to go for accuracy.
I went through a whole set of DMR style configurations on my AR before I finally found one I really liked (I’m a lefty too). Ended up with a MK12 Mod H ish build on a LH Stag upper and I prefer it over more “modern” setups I’ve owned. Lower has ambi safeties but not full ambi controls.
My biggest piece of advice is try a traditional 2-by scope over a LPVO. 600-700 223 shots are all about reading the wind, and I “see” down range so much better on my NF 2.5-10 than I did with a Trijicon 1-8 or SWFA 1-6. The LPVO reticles are chunky, they don’t have a parallax, and I was hard pressed to see what the wind was doing without a spotter.
And I mean hey, what’s the point of having a spotter with a DMR rifle? At the point you make it a two man deal, might as well bring a bigger gun.
My biggest piece of advice is try a traditional 2-by scope over a LPVO. 600-700 223 shots are all about reading the wind, and I “see” down range so much better on my NF 2.5-10 than I did with a Trijicon 1-8 or SWFA 1-6. The LPVO reticles are chunky, they don’t have a parallax, and I was hard pressed to see what the wind was doing without a spotter.
And I mean hey, what’s the point of having a spotter with a DMR rifle? At the point you make it a two man deal, might as well bring a bigger gun.
Little carnie hands is a thing. I won’t even get into my borderline T. rex arms. Thanks for the info. As I’ve only shot the hk a bit. I can’t honestly say I have actually data on it. I only considered it. As I have a buddy looking to sell one. And I happen to need something similar. I could have sworn I read on here somewhere that the hkmr556 was pretty accurate to around 1 Moa to just under moa given good ammo and shooter abilities. But regardless thanks for the input“Little carnie hands”
I would not pick a piston gun for a DMR rifle. The HK’s and LWRC’s are decently accurate but I had issues with consistentcy with them and also SCARS. Direct impingement is the way to go for accuracy.
Thank you for the solid input. I have a few scope in the 2/2.5 to 10 range I was planning on putting on it. I have a trijicon credo 2-10 and a vortex viper pst 2-10 ffp. Might I ask what company you went with for the upper. Is that a pri upper. Or a different company. Thanks and have a great day
Just snag a PRI or Larue, or call up CLE or Craddock and have them put together whatever you want exactly how you want it. The reality is that any 16"-18" 223 Wylde chambered upper with a high quality barrel and good quality receiver, rail, and BCG is going to be the same as the next as far as a DMR rifle is concerned.
Upper is a little bit of a Frankenbuild since I changed parts one at a time. It’s a LH Stag with their standard LH bolt, white oak recce 16” barrel, PRI did the SPR riser and handguard, seekins adjustable gas, Dead Air flash hider under the Sandman.
Consistent 3/4 moa groups are doable, with a lot of focus. The AR is just so much more squirrelly in my hands and the trigger (despite being the best available 2 stage geisselle) is such a step back from the Triggertech in my bolt guns. I have to really focus on follow through and returning the gun fully to the exact same position before firing the next shot.
When I just blast away as I am known to do, groups open up to 1.25 MOA or so. Still good to pound a mini IPSC at 400 and a 10” gong at 600.
I do think you could wring out a little more with better load development (I just seated SMKs at mag length and ran a 3 or 4 charge ladder) and a Lilja or CLE barrel. Big diminishing returns on ARs and I’m delighted with the accuracy I get.
Hard to beat the Seekins DMR. i feel like there is a lot of bang for your buck. They have some in stock at Euro Optic.
Much appreciated.
Sgt of arms has arca integrated handguards if you do much field tripod work. Their complete uppers get good reviews also.
Vortex 1-10 is a great scope option also. Nx8 2.5-20 good idea your doing more longer range work thanks close up
Vortex 1-10 is a great scope option also. Nx8 2.5-20 good idea your doing more longer range work thanks close up
Thanks interesting idea to run with. I don’t do much field shooting with a tripod. But it’s an interesting rail I’ll have to try at some point
Buys. mK12. Save your self the trouble. It would be the rifle if grab off the shelf if shit hit the can.
Thanks
Built a Mega Mml set and added Ambi lpk parts, just need to install my Ambi mag release. I’m a lefty as well. Added a proof SS barrel and 2.5-15 T6xi optic. I’m more than happy with this rifle.
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My home brew piston holds sub moa with factory munitions... about .8moa 5 rnd groupings with mk262's. I am confident I could squeeze better groupings with hand loads. Ymmv
Is that a 4 round group? Excellent at that range! Specs on the bullet?
Still Diggin that build brother, what's the word on your Large frame build?
Appreciate it Jake, it’s so far still my favorite. Hopefully the mega build with the Bart 6.5 creed barrel will be as good, waiting on the upper still.
Are you talking about the GGP with 16” proof CF 308 win I had issues with?
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5 rounds. It’s very consistent with several groups under .5 moa at that distance. I’m the weak link with this rifle.
77 gr SMK, 24.2 gr TAC, Cci 400, win brass.
Thanks this is the type of build I had in mind originally. But I have to clear out my gun safe and figured I’d take a lower I have and slap a good spr upper on it.
16”?
Well was looking at 16 or 18. The reason I was thinking the hk. Was most of the threads I read on it. Said it was pretty accurate. And lasted a long time. And that the 16” barrel performed well as a dmr/spr type rifle. And as it so happens a buddy of mine is looking to sell his hk upper. So seemed serendipitous. I however have virtually no experience with piston rifles. Just a few rounds through a different hk rifle. That being said I would have no problem getting a 18” upper from another company. Think if I am going with an 18” I’ll go with a pri as i like the look of the round carbon fiber handguard. Plus it reportedly has great performance capabilities. Assuming me and my carnie hands do their part.
The 6.5CM
Cancel your order, I’ll sell you mine. Taking down my whole Mega MML/Bartlein 6.5 rifle.
Have everything but the upper. They are finishing them up. Should be here end of this month to first of next.
. What’s the story here? Last edited:
Have everything but the upper. They are finishing them up. Should be here end of this month to first of next.
Bought a subperior KAC
. Can’t justify keeping around duplicate autos and bolts, been selling a bunch of my stuff of late. I’ll probably list the whole gun and see what fish I can catch if you’re only looking for the upper “chassis” though. Bought a subperior KAC
You're gonna regret getting ride of that CLE barrel.
Bought a subperior KAC
Did you buy the new PSA Sabre????
I would have probably been interested. But yeah I have everything, just been waiting on the upper/handguard as it was out of stock.
I have no doubt it’s a better barrel, but two 22” 6.5 CM semis is a gross misallocation of resources for me.
I have no experience with the HK to say other than they carry a solid reputation.
A PRI upper MK12 clone with the Douglas barrel would be extremely nice though with all the hotness.
I have a 16” Douglas barrel cut by CLE on a spr build that is extremely accurate as well. You will not be disappointed with a Douglas barrel’s accuracy.
This group is with quality 77smk loads of course.
