Building an AR as a display piece on the wall...

[clm2112]

And, in the early hours of the morning, the machining and test fitting is done. Had a little mistake happen during the milling that I didn't find until attempting to fit the trigger. The floor of the receiver wasn't deep enough. I must have goofed setting the stop on the quill.

So, had to load the receiver back into the jigs, set everything up and make another pass around the bottom of the trigger pocket. Cleaned and vacuumed every thing up a second time. And then it worked. Floor is now low enough to allow the safety selector to be inserted over the tail of the trigger.

The finish has to wait for a while. My original Olympic had an odd color to it. More of a parkerized grey than black. Just looking at photos of other rifles, there is quite a bit of variation in the colors used. They must have had some problems figuring out the coating process... some are jet-black, some are gloss black, some are dark grey, and some have a greenish tint to them that looks more like cosmoline over parkerizing. I guess I'll figure out what I want my copy to look like. I'm still planing on giving it an alodine bath for corrosion resistance (turn it zinc-chromate green) before painting it.

Meanwhile, I can move on into the next bit of this project.

 

[clm2112]

A little progress... and a throw of the dice.

I ordered a stripped A2 upper from Delta Team Tactical / Davidson Defense. This is the roll of the dice, since the company's reputation is quite frankly dog-shit. I don't know when it will arrive. And, we will just have to wait and see if they managed to screw up an aluminum upper. While hard to do... this design is 1960's technology intended to be mass produced... it is still possible to mess up. It was exotic back then, but sixty years later it is a well understood material and design.

When we get right down to it, it doesn't have to actually work. It is just a place holder for the other parts that hang off of it. I will attempt to make it completely functional and will be pleased if it does function properly, but again, it is a wall hanger and doesn't have to work.

 

[clm2112]

Wall mount printed! eSun PLA+ at 225 degrees, 90 degree bed, 0.4mm, 50% fill using cubic. Took 16 hours to print, but it looks like it is going to work.

Time to dust off the wood-working skills to make a plaque to put the hanger on. It doesn't have to be as long as the rifle, but it does need to be long enough to span a pair of studs in whatever wall it gets mounted to... I don't trust the plaster to hold the weight, so it will get screwed directly into the studs.

 

[clm2112]

A little more progress this weekend. Spent most of it sitting on a chair and coaching a co-worker while he used my milling macahine to finish his 80% AR. (He got half-way through the process in a four hour session, to be picked up next week to complete it.)

Meanwhile, the package from Delta Team Tactical arrived. The A2 upper looks OK. I'll still have to fill it out with parts to be sure, but it looks correctly machined. The base forging is from Brass Aluminum Forging Enterprises (square mark) and the coating is matte black. Basic checks of pin fit to lower, barrel nut, charging handle slot, and bolt carrier bore done... so far it looks like it is going to work.

 

[Bobster]

Spent most of it sitting on a chair and coaching a co-worker while he used HIS milling macahine to finish his 80% AR. (He got half-way through the process in a four hour session, to be picked up next week to complete it.)

At the risk of sounding like a fudd (and I most certainly am NOT ), on this and any public forum you should probably exercise discretion in describing that you allowed someone to use your equipment to "build" a gun. Just looking out for a fellow gun eNthUsiasT!

PS: I fixed it for you...

 

[clm2112]

Not much progress on my little project.

Though, the fellow came back for another session on the milling machine. He did manage to snap a 3/8 HSS 2-flute end mill. It happened while milling the deep part of the trigger pocket. Loaded a spare and he continued on, a little slower on the feed with more cutting fluid. In the end, it was an acceptable lower. He made it through the clean-up and first time assembly. I checked it over for function of the fire controls, and a few minutes later we were outside drilling a few new .223 holes in a tree stump.

Another convert to the black rifle is born.

 

[clm2112]

Back to this project for a few minutes. While doing the parallel project of building an actual service rifle, I got an upper parts kit for the wall hanger. Really, just the forward assist and dust cover hardware from Aero Precision. Only took a few minutes to install with no issues. It looks like the A2 carry handle upper from Delta Team Tactical is going to work just fine as an actual, functional, upper.

Barrel selection is on hold for the moment. I'll see how the Green Mountain barrel performs on the other upper first. If it is a dud, then I'll transfer it to this upper for display purposes.

 

[clm2112]

Now that the holidays have past, got another piece of the jigsaw puzzle to add. Time for the A2 carry-handle upper receiver to get an appropriate rear sight

Parts arrived from Fulton Armory a few days ago, though I suspect these are Rock River parts. My old service rifle came with the NM sights and was originally a DPMS assembly, so after himm-hawing around about it, I decided that the wall hanger should have them as well.

There are three different versions of the A2 sight assembly:

The original was used on the 20" A2 rifle with the carry handle cast into the upper receiver. It has coarse threads on the sight threads that allow elevation adjustment from 0 to 800 yards, in 1/2 MOA steps. The adjusting drum is in three pieces to allow the rifle to be zeroed and then the marked drum set with the markings showing the elevation settings.

The second version was used on the detachable carry handle intended for the flat-top rifles and M4 carbines. It is a little shorter (to stay within the dimensions of the removable carry handle casting) and has the same coarse threads. By being shorter, it can only be elevation adjusted from 0 to 600 yards in 1/2 MOA steps.

The last version is the commercial "National Match" rear sight. It has fine threads that adjust elevation in 1/4 MOA steps. The adjusting drum isn't marked for elevation settings, since it will need to completely rotate around to go from 0 to 800 yards. You add the markings yourself after sighting in the rifle at different ranges. My preference is to punch mark the zero into the drum, then count clicks for the distance (cheat sheet of come-ups on the back of my clip board.)

Another modification of the A2 NM is that the stock aperture is drilled out and takes a threaded aperture that can be changed out. So you pick the smallest aperture that transmits enough light to get a clear image. Cloudy days might need a larger aperture, bright sunny days a really small one. On my original upper, I had to make this modification myself. The one I just got from Fulton already had this done.

The first step of the installation is to fit the sight to the upper receiver. My old sights were kinda of sloppy, with a gap between front surface of the sight and the carry handle. It wasn't bad enough that it required pinning it. This new one is a very tight fit. Tight enough that I took a little material off the sight to loosen it up. Not much, a little work with emery cloth, then polished out the bare metal and applied bluing to the new surface.

Perfect fit. No wiggle to the sight and it moves smoothly up and down. I don't see any need for having this one pinned. The ball and spring will close up the gap just fine.

Time for a cup of coffee before the hard part starts... assembling it with the springs, roll-pins, and ball bearings. I always feel like I could use an extra couple of hands every time I do this.

 

[clm2112]

Ok, here we go...

First the sight, drum, detent springs, and detent ball bearings need it go in. I use a lot of assembly lube to stick the springs and ball bearings into their respective holes while getting it together in the upper. Once the drum is threaded into the sight, position it so a 3/32nds punch will pass through the receiver and dial the sight up to its maximum elevation. That will get it lined up so the spring and roll pin can be installed with the least amount of force compressing the spring.

Next step, start the roll pin in and drive it until it is just about flush with the bore in the sight.

Now over to the vise for the operation that needs an extra couple of hands....

Now, to compress the coil spring and drive the roll pin the rest of the way in. Without launching the spring into orbit. I use a punch to push down on the spring, and the 3/32nds punch to trap it from the other side of the receiver. Then slowly tap the roll pin in, and drive the 3/32nds punch out. When it works, the spring ends up under the roll pin and under compression. (This is what takes the slop out of the A2's elevation mechanism.)

And success... The roll pin is in, which limits the elevation travel so you don't accidentally un-thread it on the firing line. This really is the only hard part about putting these sights together.

Time for another coffee break before going to work on the windage parts.

 

[clm2112]

Last little bit for the evening.

Prep the windage knob by driving the roll pin about one third of the way in.

Lube up the flat spring and place it in the sight

Lube the windage screw and start threading it into the aperture. This takes a little fiddling around, since you have to compress the flat spring to get the holes to line up. Pressing on the aperture with your thumb while winding the screw to the maximum left windage will get the screw into the hole on the right side of the sight.

Line up the screw so the hole for the roll pin is in a know position, and prep the windage knob by adding the spring and detent ball bearing. More assembly lube to keep the ball in place...

Press the windage knob on and use a 1/16" punch the line up the holes with the windage screw. It is ready to stand up on the barrel nut and drive the roll pin it (which will push the punch out.)...

And that is all there is to this. Sight installation complete, ready to go back into the safe and wait for a barrel assembly.

 

[Michele]

Really nice post with details

 

[NavyVet83]

I like this. You say it'll be a wall hanger, but apparently it'll be a very useable wall hanger if need be. When you first started the thread, I was figuring it was gonna be strictly a display piece to hang above the couch or something. I wasn't thinking a fully functional, detailed rifle..

 

[clm2112]

Yeah, since the feds would treat it as a fully functional rifle, it might as well be one.

When it is hanging on the wall, it will be missing the hammer, hammer spring, and the BCG... which will create the space needed for the gag sound unit. Otherwise it will be complete. The upper will be test fired and sighted in, so... put in a hammer and BCG and it will be ready to shoot.

 

[Pern]

I like this. You say it'll be a wall hanger, but apparently it'll be a very useable wall hanger if need be. When you first started the thread, I was figuring it was gonna be strictly a display piece to hang above the couch or something. I wasn't thinking a fully functional, detailed rifle..

All my wall hangers have full 30 round mags in them.

 

[clm2112]

Range Day for the wall hanger! Finally, after months of cobbling this little bit of nostalgia together. Barrel installed and furniture from the 1980's

 

[Bongo Lewi]

Looks great!

I debated putting together a classic M16A1 with the triangle hand guard or buying one of the fashionable clones like Brownell was selling at the time. But on the DIY I couldnt find a Colt lower or repro that looked as original as I wanted. I hesitated and BOOM the repros were sold out/discontinued and I still couldn't find a lower that made me happy.

 

[no4mk1t]

Looks great!

I debated putting together a classic M16A1 with the triangle hand guard or buying one of the fashionable clones like Brownell was selling at the time. But on the DIY I couldnt find a Colt lower or repro that looked as original as I wanted. I hesitated and BOOM the repros were sold out/discontinued and I still couldn't find a lower that made me happy.

PSA bought H&R in the bankruptcy and is selling retro H&R marked lowers if that floats your boat.

Intlmilco makes Hydramatic marked lowers.

This company is making 80% M16A1 lowers if you want to go that route. They can laser engrave the markings you want.

M16A1 – 80 percent receiver – CryoStructure

www.cryostructure.com

I don't believe Colt sells lowers, so you'd have to find one of the re-issue rifles on the used market.

Other outfits sell the retro parts if you want to build an early 601 gun with triangle C/H and ping pong bolt catch etc.

 

[Bongo Lewi]

PSA bought H&R in the bankruptcy and is selling retro H&R marked lowers if that floats your boat.

Well I'll be damned. That's almost exactly what I was looking for. I gave up several years ago, stopped looking. 10-4 on the Colt lower. You have to buy the entire gun if you can find one. The real thing is 7-8 grand. The Colt repro runs 2000-2800. Seems pricey.

I thought it might be cool just for grins to put a binary trigger in a repro to sort of emulate select fire. It would be just a fun gun for me. My older brothers are both VN vets and I recall them writing me and sending photos when they were deployed. I thought they were having fun playing Army, which of course was not the case. Around the same time I went on my first pheasant hunt. The only gun I had fired was a 28 ga shotgun and my cousin's 22. I was fascinated by their M16s.

 

[clm2112]

Productive little trip up to the range. A light drizzle was falling from the sky, so I only got 20 rounds in to zero the upper's sights. No problems with the rifle's function, which is pretty much what I expected since the bolt, barrel, and lower have all been used before, this is just putting all the pieces together into one finished rifle. Not quite perfect, with the F marked front sight, but I was able to run the front sight down far enough to zero it with the carry handle upper. (F marked front sights are slightly taller for use with detachable carry handles.)

 

[no4mk1t]

Well I'll be damned. That's almost exactly what I was looking for. I gave up several years ago, stopped looking. 10-4 on the Colt lower. You have to buy the entire gun if you can find one. The real thing is 7-8 grand. The Colt repro runs 2000-2800. Seems pricey.

I thought it might be cool just for grins to put a binary trigger in a repro to sort of emulate select fire. It would be just a fun gun for me. My older brothers are both VN vets and I recall them writing me and sending photos when they were deployed. I thought they were having fun playing Army, which of course was not the case. Around the same time I went on my first pheasant hunt. The only gun I had fired was a 28 ga shotgun and my cousin's 22. I was fascinated by their M16s.

If the SC ever rules favorably on FRT's, that would be as close as you can get without a tax stamp. Not that I'm looking for that to happen...