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Discussion Starter · #1 ·
Things that can happen as you get old ….

First post here and tried to make it interesting. I’ve lurked for a long time and learned a lot about things to do and some not to try. I’d not seen this before. If it is old news – sorry.

Instead of riding up the hill in the Jeep with everyone else, I decided to provide something and walk up the hill with my USC conversion (UMP-ish). Almost got to the top too when the forces of age and gravity took over and weapon and I came down the hill at a greatly accelerated rate. The front sight was MIA. The left rear sight wing was cracked, part was missing, and the rear sight had an inch or so of swivel.

The smart thing to do at this point would have been to install a new front sight, section off the rear sight wings from a donor (which I had), and ask one of the folks here to weld the rear wings back on. Since this would have been the smart thing to do it was rejected in favor of trying to make it a flat top.

This happened in the days before the extended top rails that are now available. The short rails always bugged me since I couldn’t get my red dot on the rail with my night vision scope. If I just used the night vision scope with no red dot it was still a problem due to the height of the rear sight wings.

First effort was to get one of the 12 inch rail stock pieces advertised everywhere. The rear sight wings were completed removed and holes drilled in the rail to go over the rail mounts. A couple of problems showed up. First, while many of the people selling these rails claim they are Picatinny standard, they lie. The ones I got were all Weaver. My ARMS mounts have never gotten along with Weaver and some things like my Eotech and 40L rear sight were a no-go. Second, it is a long way from the front rail mount forward and there was a little movement in the rail in relation to the receiver. I didn’t take any pictures of this effort and have since junked the rails.

Second effort was to get some 18 inch rail stock form EGW. I do have a mill vise but we are trying to sell our house and move and all of my shop tools are sitting in a POD somewhere. This was done with a Dremel and hand drill – no laughing. In order to provide support at the front of the rail the front sight was flattened, the ramp removed, and the rail notched to fit in. Also a hole was drilled through the rail so that the standard front sight pin could be used to secure the front of the rail. I never got around to cutting it down to the proper length. This worked but the rail stock being .96” high put standard AR sights way too high.

Current effort was to go to someone that had a mill vise. The EGW rail stock was cut down to .37” high and tapered at the front to fit in the front sight base. It was also milled out to allow the roll pin to be inserted and provide support. The rear sight mount was not drilled all the way through. It was just drilled enough to act as an alignment aid. The stock rail mount bolts were used in the other two mounting positions.

To bring the sight height back in line with the drop of the folding stock, Troy Micros are being used as the BUIS.

This works fine and there is now a lot of real estate for mounting whatever. Another benefit is the flex that the upper used to have is now gone. I didn’t keep any pre-rail targets to compare before and after accuracy.

If I had to do it all over again I would ask someone here to do the front sight ramp and rear sight wing removal to provide a more level and professional look to the top of the receiver. Using the lower rail also means that the flattening of the front sight base isn’t necessary. Lastly I’d have the rail at .41” instead of .37”. .37” is not quite tall enough to allow the mounting bolts to be fully recessed.

Hopefully this will be a worthy first post.

My photographic skills suck but now for the pr0n –

The UMP-ish with front sight ramp and rear sight wings removed.



The second effort rail.


A close-up of the taper at the front of the rail.


The second effort rail mounted.


The current rail.


A close-up of the front taper.


The current rail mounted.


A close-up showing the front sight with the roll pin installed.



Rail and sights mounted.
 

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That looks good how is it when you have the cocking handle locked back does the rail interfere with it. Also hope you are ok. That is a nice mod
 

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Discussion Starter · #4 ·
While it is close, the cocking handle doesn't actually touch the rail. I don't have my feeler gauges but I can slide several sheets of paper between the two freely. With my palm down release my finger never really touches the the rail.
 

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Bloody nice!
 

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Slicker than snott!!! VERY nice!!!
 

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Wow, NCTraveler, first you give me a story involving both Jeeps and HK's and make yourself my new personal hero, then you go and do a sweet mod that even the mod-master Chopstix Kid loves. I love it too!
Nice work, great write up, and kick ass first post! Welcome!
 

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Discussion Starter · #11 ·
I'd never seen that one. It really has a finished look. Nice find.

I lived in Germany for a while and speak some German but am rusty. It looks like they are saying front and rear sight is removed and black rail installed via bolts (or screws) - they don't say how. "Modification is permanent".

Just over $300 USD not including sights.
 

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that is pretty cool, and definitely an improvement.... good job.
 
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