Ma Tech rear BUIS on MK12 Mod0 SPR

[airman23]

Hello all. I"m just about finished with my MK12 Mod0 SPR build. The last part I was going to get is the A.R.M.S #40 Low Profile rear BUIS However I Have a 20" A4 AR-15 flatop rifle with a MaTech Mil-Spec Rear Back-up Iron Sight and I'm thinking of just taking that off my A4 and putting it on my SPR. This will SAVE me $129.00.

https://www.amazon.com/MaTech-Mil-Spec-Back-up-Iron-Sight/dp/B002E6SXN4

Will the Ma Tech Rear BUIS work with the PRI Flip-up front Iron site?

https://www.precisionreflex.com/Detail.aspx?PROD=186686&CAT=4292

I have a A2 detachable Carry handle I can install on the A4 to replace the Ma Tech. What to you think. Will the Ma Tech get in the way of any Optic on the SPR?

I have the Nikon M223 3-12x 42 SF Rifle scope in a American Defense AD-RECON mount that I was going to transfer to the SPR and use the A4 with the detachable carry handle to practice with the Iron sights.

You prompt replies will be appreciated

[Kwikvette]

Being in CA, we can't have select fire so that eliminates us being able to obtain an identical MK12 clone.

At that point, it boils down to how much you want to spend.

The closer you get to the real thing, the more it'll cost you and that's not including the hard to find parts.

If I were you, I would just buy the ARMS sight for a clone points. In fact, I need to buy one now since I haven't replaced the one that came with my MK12

[FMJBT]

If you are using the monolithic top rail setup for the Mod 0 (Either A.R.M.S. or PRI), you'll need to trim the back end of it as they are specifically contoured to interlock with the A.R.M.S. #40 rear sight.

Also, the ADM Recon mount will likely put your scope up much higher than it should be if you bolt it on top of the top rail of a Mod 0. With the height of the top rail, medium height rings are what you'll need for a decent cheek weld.

[Nguyen]

Being in CA, we can't have select fire so that eliminates us being able to obtain an identical MK12 clone.

At that point, it boils down to how much you want to spend.

The closer you get to the real thing, the more it'll cost you and that's not including the hard to find parts.

If I were you, I would just buy the ARMS sight for a clone points. In fact, I need to buy one now since I haven't replaced the one that came with my MK12

Correct me if im wrong, but true MK12s are semi-auto.

[ssilver88]

Correct me if im wrong, but true MK12s are semi-auto.

They were originally built on old A1 receivers with KAC full auto 2 stage trigger group then later on switched to Geissele 2 stage full auto triggers

[Ki6vsm]

Getting back to whether or not the sight will work....

I don't have a Mk12 clone or anything even close, but I do have an upper with a MaTech BUIS and an SWFA SS 3-9x mounted via Bobro QD mount. The MaTech does clear this scope. Barely. The MaTech sticks up kind of high, as you can imagine. I actually beveled the inner corner of it with my Dremel. See pic below for illustration. And then I treated the exposed bare steel with some cold blue. Now the sight clears the scope with a very comfortable margin.

No way to know if your Nikon-AD combo will fit until you try.

[Ki6vsm]

Will the Ma Tech Rear BUIS work with the PRI Flip-up front Iron site?

I forgot to address this question. The upper that I mention above also has the PRI flip-up front sight! So it bloody well better work. LOL Haven't had it out to the range yet. I built this upper recently.

Actually, I don't know why the two wouldn't work together. The PRI is supposed to be standard-height, fitting M4, M16, and AR15.

[Bansh88]

As long as the Matech is mounted onto the upper receiver flat top, it should work.

[Kwikvette]

Correct me if im wrong, but true MK12s are semi-auto.

I had been attached a few times to '21s and their team leader's MK12 sat on an A4 lower which had safe/semi/burst.

I can't say whether or not that's how all MK12's were issued but I can say that any select fire rifle I've seen (and used) in service has semi-auto as an option. Whether it has 3-round burst or auto comes down to the rifle itself and issuing company. For instance, my M4A1 was safe/semi/auto.