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Will the aimpoint acro fit the FN Five-seveN MRD pistol? If so will it cause any cycling issues?

Well the rule is 3.0 oz for total overall weight of sight and base for reliable functioning. Both version have to have a conversion plate since both us a rail mount, So you would have to find a mount to interface between the slide and sight. I doubt you would be able to get a plate and keep the weight below 3oz. Also it would be sticking up VERY high at that point.
 

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Thanks for the info.

I called FN to ask about a "3 ounce rule" for max optic weight on the MKIII. No one there has ever heard of any such rule. They did state cycling should be reliable for compatible optics (Aimpoint as you know not being one).
 

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I spoke to FN. They said it is not compatible. They don't even offer a plate for it to use on the Five-seveN o
This was my biggest complaint about the MRD system. Overly complicate design that had built in limitations on sights you could use. hence my comment on my banned video the perfect MK3 would be the MRD lower with MK2-Gen2 slide with DT CAOS set up.
 

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Disagree that such a Franken 7 using an after market slide cover which a poster sells would be superior to the MRD.

Setting aside reports by some of excessive flex and screw issues with the DTCAOS slide, I do not see it as offering any advantage over the MKIII.

First, the 6 plates which are offered for the DTCAOS are all out of stock, and infrequently available.

Second, assuming plates ever come back in stock for what may become a legacy model, the conclusory claim the DTCAOS offers any substantial increase in optic choices is not accurate, or most charitably, unsupported.

The MRD is compatible with: Leupold DeltaPoint Pro, Trijicon RMR, Vortex Optics, Burris FastFire series, Docter Optics, some not requiring a plate (DTCAOS, to my knowledge, does not allow for any direct mount options, and is therefore actually less flexible).

I do not see anything at all offered to support what seems to be a just a conclusion,-- that the MRD is “overly complicated. Nothing is identified as mechanically unnecessary.

Of course, one could criticize the looks of the MRD, but if the discussion is simply a matter aesthetics, I myself prefer it to the look of the Franken 7. Not a fan of a 57 with a slide cover that reads “Dorian Technologies.” I find the front slide serrations of the MRD superior. Also, looks aside, I have not seen any reports of excessive slide flex on the MRD, or issues with mounting screws. The MRD accommodates most mainstream choices, some even without plates.

Sure we can all think of ways the MRD could be improved per our own personal preferences, but the Franken 7 would, in my opinion, be a very big step back from the MKIII’s advancements.
 

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Thanks for the info.

I called FN to ask about a "3 ounce rule" for max optic weight on the MKIII. No one there has ever heard of any such rule. They did state cycling should be reliable for compatible optics (Aimpoint as you know not being one).
If you’ve been around the fiveseven platform long enough you would encounter lots of discussion regarding the reliability of the fiveseven cycling with an optic. The “3 ounce rule” is not something fn coined or jwolf.

I got a chance to shoot an MRD with an SRO on it today and that was pretty awesome. The staccato with the ACRO on it made it seem a lot larger and bulkier than it actually was. I’d have to wonder how big it would be on the fsn, weight aside.

I’m about to pick up an mrd and through a 508t on it. Hoping it’s the perfect size/weight. The 507k is so flush though…
 

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2.1 oz for the sight without base.

3oz is the max you can go and still have a working gun.

Base weighs about 1.2oz plus 2.1 for the sight.

Not only slide cycling issues but the heavier the sight the more the 5.7 recoil impulse tears up the sight and breaks stuff.
The additional claim that the heavier the optic the more the recoil impulse will be, is contrary to the laws of physics.

Newton’s second law: F = m a (The acceleration of an object depends on the mass of the object and the amount of force applied).

Under the fundamental laws of physics (which are incorporated into all basic engineering principles), added slide weight (heavier optic) must therefore reduce recoil impulse--not increase it.
 

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The additional claim that the heavier the optic the more the recoil impulse will be, is contrary to the laws of physics.

Newton’s second law: F = m a (The acceleration of an object depends on the mass of the object and the amount of force applied).

Under the fundamental laws of physics (which are incorporated into all basic engineering principles), added slide weight (heavier optic) must therefore reduce recoil impulse--not increase it.
While I do not disagree with you regarding the basic laws of physics, I made no mention of newtons law. You do have to understand, though, that there is more to it than recoil impulse. I do not claim to be a math asian but I am savvy when it comes to physics and engineering. I am a manual labor asian first and foremost, but my career choices don’t mean I’m less of an engineer then anyone else on the internet. In fact some may consider me an engineer of humanity. In short I had sex and conceived children.

When it comes to the operation firearms I think you’re over simplifying it. Just because adding weight reduces recoil, doesn’t mean that it will cycle the action enough to load the next round.

It sounds like we all agree that the 509t is not recommended anyway. The added weight from the 509t and it’s hardware would probably still cycle some of the hotter or perhaps heavier rounds though. When it comes to the mrd, I have yet to see someone actually mounting a 509t and testing how it runs. Remember the MRD is physicscally different from the mkii and usg.

Normally I’d say just wait for Matt, Buffman, to figure it out but he’s got a lot on his plate already and body armor is an invasive species. Time will tel. It just takes a much longer time with the fivesevens, in general, across the board.
 

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When it comes to the operation firearms I think you’re over simplifying it. Just because adding weight reduces recoil, doesn’t mean that it will cycle the action enough to load the next round.

It sounds like we all agree that the 509t is not recommended anyway.
I did not say that increasing weight will increase reliability. I pointed out only that the repeated claim there is a "3 ounce rule" was unknown to FN; and, the additional claim that added weight increases recoil impulse is contrary to Newton's 2nd law.

I made no statement whether any particular model offered by Holosun is "recommended" or not.
 
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