I’m looking for an ideal absolute cowitness setup for my AP5-P that’s arriving next week.

I have a few red dots lying around that I was planning on trying: 507c, Burris Fast Fire 3, and few others.

Would the Battle Steel optic mount be an ideal solution? It seems to be the one I’m seeing most often.

Also, is there any other optic setup that I should consider? It’ll mostly be a range toy but perhaps a truck gun as well given it’s size when folded.

MFI makes a great mount.  They have one that is angled to keep you from slicing your hand up while loading the shorter MP5 type firearms.

If you use a scalarworks co-witness optic mount, you can still see your irons and will get a cheek weld similar to Unity height assuming you are using a stock or brace that mimics OEM HK stock height relative to the receiver.

I’ve found the taller optic setups to work very very well.

I'm very happy with my Battle Steel and Holosun 507c co-witness setup

The battle steel work great but I’ve moved to the MFI and scalar works mount instead. I just prefer the height and the optic not being as cluttered with the irons.


The ultra low profile have been impossible to find for the last few months so I’m trying this with one of my K’s but you lose the backup iron sights.

I'm going through the same process right now with my AP5-P.

I was thinking a QD mount on any rail would be fine, but the problem is:
1) I need the optic kinda low to be comfortable--I don't like chin-welds, so the tall stuff doesn't work well for me. MAYBE I can get over that.
and
2) I need the optic kinda high to get the front sight and ring from blocking too much of my view--not a big deal at 5-10Y, but at 25-50Y it drives me nuts.

My first plan was to put a LARGE windowed optic on a very low QD mount to give me more lens to see around the front sight. An Eotech sits too high, but maybe one of the 30mm tube optics like the nice Holosun 530 or an Aimpoint PRO or whatever. I haven't ruled that out.

Now I'm leaning towards trying the Holosun AEMS on it--it won't be very low, and the lowest mounts don't appear to be QD (though sometimes you can get a QD latch for that style). The Trijicon MRO may be an option, but I hated the first gen versions due to weird distortion and magnification and tint and stuff. I'm assuming they're much better now and see many on MP5s.
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IF money were no option I'd get a pic rail welded on and have the front sight given the "european cut" shaving off the top of the ring. But that's like $500-$600 of welding and cutting and re-coating.
It's still my "nuclear" option.
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I tend to like a lower mounted optic even though I know the trend is to go taller. I also hate crowded views (I never understood how people ran cowitnessed irons with micros on their ARs, but I know some hardcore dudes into that setup).

When I look at the few PCC shooters using MP5s, they all tend to be using Eotechs mounted on very low (welded I think) pic rails as well as Micros on tall mounts. So I may just have to adopt to the chin-weld.
** I SUSPECT an actual stock--like the UMP stock--would make using a taller optic more feasible. The brace is short and low.

Don’t think of it as a chin weld.

Think of it as a heads up shooting position.  When you toss on armor and a helmet, it’s far more natural and less fatiguing.  Less eye strain too since you’re not always looking up.

After going to taller mounts, getting behind anything lower 1/3rd or lower height (on an AR)is comically awful.

It also negates the HK irons issue.

To get around that, I swap the rear drum out for an HK33 or HK91 drum that has the notch.  So the dot sits right on the front sight post but I don't have the rear aperture cluterring the view.  
If optic fails, I just rotate the drum to an aperture position.

I don't have a picture handy but for comparison, I do the same thing on my UZI SMG's.  I drill out the 200M aperture to be very large and I can always flip back to the 100M aperture if optic fails / battery dies etc..
Old pic showing what I'm talking about.  Similar setup on the MP5.

I did the same with mine when it was setup with the battle steel and used the castle rear right on my K to do somewhat the same thing.  It works well and I do like it, but the higher up (not too high) sights work great for me.  

I agree, heads up is really the way to go but without going overboard.

The goal is to get the front sight hood out of the FOV from the optic.

I've found that 45mm off the top of the receiver to optic center line is the sweet spot for the full size. And 43-44mm for the K.

46mm would be ideal but it's difficult to find an RDS mount and optic rail combo without going over.

45mm puts the tippy top of the sight hood in the very bottom of the optic, a T2 in my instance. 46mm would probably get rid of it but it's hard to find mounts, as stated that get this number.

Example One: On my SP5s, I have the HK MLI optic mount (13.2mm from top of the receiver to top of mount) with a 30mm Aimpoint mount (Actual is 31.2mm) providing 44.5mm optic center line.

Example two: On my MKE AP5-M, I have the factory MKE mount (11.8mm from top of receiver to top of mount) with a 30mm B&T Acro mount (Actual is 31.1mm) and Steiner MPS providing 42.9mm optic center line. I cannot see the front sight hood at all due to it being much close to the optic. You might see it with a T2 or similar.

Example three: PTR 9CT, I have the welded on optic rail (6.8mm from top of receiver to top of mount) and a 1.42" absolute height optic mount (Actual is 36.65mm / 1.44") providing a 43.5mm optic center line.

With these setups, you lose the use of the irons unless you get a Scalaworks or something you can see through. I just converted all my optic mounts to QD so I can remove them if the need arises.

It's a couple of years old, but here's a good example.

https://www.strikeindustries.com/si-rex.html

Yeah, I'm sure armor, helmets, NODs, and not really needing to get as low as possible to the ground, etc., are why the tall mounts started trending (even if most civilians won't be using/needing much of that).

I'm just gonna be shooting PCC tournaments and using it as HD. I have kids in the house, so speed is more important than helmets and armor (I actually don't own a helmet and only use some hand-me-down AR500 body-armor to wear as a weight-vest now and then).

But if others can adapt to it, I'm sure I could get used to it.


I have an MFI mount (10.7mm tall) and will try out an AEMS in a low mount (30.9mm = overall 41.6mm tall).

I think it will help a lot to SBR it and get a stock with a taller comb...the brace is short in comb-height and LOP (even with my stubby arms and stubby neck).

Even without the weight of armor and helmets, the taller mounts have been a massive benefit to me.  Natural body position, with a back injury or two, really make a difference.

It’s worth a shot.  I put it off, then decided to try it. In short order I found myself replacing optic mounts and haven’t looked back.

I use an MFI mount and a Larue QD mount with a Holosun 503.

I use a B&T low aimpoint micro mount (BT-10266) for mine with a holosun micro.

Something like this?

https://www.m8industriesllc.net/new-products/hk-mp5-sight-base-rmr-mount

The MKE mount works pretty good. There's an image further up this thread with it installed.

You can check out the HK specific Shield sight mount.

Also, MFI  and some others have K mounts as well.

I know it isn't exactly what you are look for, but the functionality of my MP5 clone jumped up exponentially when I switched from a red dot to a PA 2x prism...

Attached File

I used the factory mount and shitty sig msr green dot.

Attached File

They make a 5 slot pic rail that mounts on rear sight weldment.  It even has a dovetail for a glock rear sight as a buis.  I just put one on my ap5-p.  I tried a battlesteel with a t2 size optic, got tired of busting knuckles and just being to busy around charging handle area.  I ended up with a mke mount somehow, I cut the front half off, retained rear lug and rear legs.  I mounted a 508t on it, great clearance for charging handle and seemed ideal.  Noticed I was getting some binding on carrier from receiver being squeezed in by mount.  Ended up with the m8 5 slot, standard glock sight is on for buis.  I haven't decided yet on optic, I like a tube red dot for its all weather ability, but the 508t is a nice fit for a k.

No problem.  It seems pretty secure, just degrease the threads in weldment well.  It mainly relies on the new screw to secure it, but also uses windage screw to make it more solid.  If you get one, follow mounting instructions and it's straightforward.  I'm not sure I'd mount anything bigger than a t2 size optic, but then anything bigger than a t2 is kind of silky on a k model.

Good question.

I wound up getting the Botach battle steel mount for my AP5P and it looks clean and works well. I had a Fastfire 3 lying around which seems to 1/3 cowitness alright.

Problem: if you’re not careful when working the charging handle, say goodbye to your hand.

At this point, I’m thinking I may just go with the SMS2 with the integrated mount.

The low B&T and a T1 work good for me on my AP5P.  My K clone has a castle aperture which makes for an unobstructed view compared to the standard hole aperture.

Honestly I'm surprised by mine. It's small but the open fov just works well.

What stock is this?

https://safetyharborfirearms.com/product/kes-mp5k-pattern/

Where did you get the MFI and Scalar Works mount, I looked on mfi but didn't see it and it looks like they only have the long ones?

Thanks

Bumping this back up to see which optic mount is pictured?

Looks like an MFI Ultra Low Optic Rail and the dot is on a Scalarworks LEAP 04.  That MFI rail is hard to get at the moment because it's so popular.

https://hkparts.net/product/ultra-low-profile-hk-red-dot-mount-aimpoint-primary-arms-vortex-burris-fits-all-hk-models-p17962.htm/

https://scalarworks.com/shop/quick-detach-mounts/leap-04/

My LGS had a Shield mounted on an AP5. I looked through it and it was co-witness. Definitely not the finest quality optic but this model is made to mount on an MP5 and is far enough back you won't rap your knuckles on it when charging the gun

https://atlanticfirearms.com/shield-sms2-optic

I bought this from hk parts https://hkparts.net/product/low-profile-rear-sight-base-mount-10-slot-hk-mp5-mp5k-usa-p18236.htm/


I just ordered it last night so no feedback yet. After smashing my fingers on the ap5 claw mount when I rented one before buying I knew I wouldn't be using a forward set claw mount.   I don't mind losing iron sights as my dominant eye is farsighted due to prk correction and it makes irons hard to use.  Gonna be using a pa prism which is etched anyways so no worries about dead electronics.

I talked to the owner of MFI and he said he makes the ultra low profile mount exclusively for hk parts.  He said he’s thinking around the first of the year he’ll have more shipped to them.  Until then, nothing available :(
I actually do like the longer one quite a bit.  You lose the buis, but the design really is better to not hit your knuckles on it.

There is a company that makes a mount for an RMR that replaces the rear drum.  I've been thinking of trying it out

Double post

Picture?  It was over email.  Maybe I can find it.  He didn’t give a date just that it would probably be closer to the end of the year. No other info on it.