Norinco CQ311 Lower Build, and the headaches that entails

As mentioned before, I hummed and hawed over refinishing this lower for the perfect Mk18 with A1 lower clone build, but it wasn’t worth the possible legal headache that would surely accompany that endeavor.  

So I took a can of flat black Krylon primer and hosed down the lower to cover up the original glossy grey finish.  At least the paint is easily removable if the need ever arises.

So the finish looks great in these photos, but it soon degraded into a semi-gloss after handling the thing when I installed the AR Stoner LPK.  The factory markings are also all clearly visible in person compared to what appeared in the photos.

A comparison between the A1 profile lower above and a standard A2 profile lower before.

I was planning on using this lower for my Mk18 Mod 0 clone, but more on that later and how it was not meant to be.

Looks great, too bad it didn’t work out.

The inexpensive AR Stoner LPK.  Packed in some sort of oil, everything I needed was included.  I’ve read some reviews of this kit and some customers indicated their kit was missing parts, but thankfully mine came with everything.

The first hiccup I noticed was the AR Stoner A2 grip.  It didn’t fit the Norc lower so I tried to see if it would fit a standard A2 lower and I found it did not fit my Colt LE6920 lower.  Guess the grip is the one not in spec, but it wasn’t a huge deal because I have a bag full of various unused A2 grips from other LPKs.

As you can see, not all A2 grips are built the same.  This one from who knows where isn’t perfectly contoured to the lower.

This A2 grip fits perfectly to the Colt lower.  It didn’t matter because I was going to use an A1 grip that actually did fit the Norinco lower.  These are all the parts I thought I would need to get the Norc lower up and running for my Mk18 clone.

The AR Stoner LPK packed in bacon grease.  Kidding, it’s not bacon grease, but seeing as how these parts could have easily come from off short, who knows what it is.

As with a recent lower build I did recently, it helped to lay out all the parts against my matt to make sure I had all the parts I would need to complete the lower.

Things were going smoothly and I felt confident enough not to refer to Youtube videos for guidance.

Mag fit fine and fell freely when the mag release button was depressed.

Next up was the bolt catch roll pin but first a little dab of CLP to ease its entry.  I’ve recently read that some people will file one end of the pin as well to give it more of a taper.

I got the pin started and left it part way in to install the bolt catch, bolt catch spring, bolt catch plunger.

Once everything was in place, it was just a matter of tapping in the roll pin completely.

Next up was the front take down pin, spring and detent, my second speed bump in this build.  In the following pictures, it looks like everything went smoothly.  What I didn’t take a picture of was the spring and detent flying off into space and landing somewhere in the shag carpet which lines the floor of my gun room.  Why?  Because I did everything like normal, but I didn’t test fit the takedown pin to make sure it fit the receiver.  I just assumed it would, but it didn’t.

Anyway, after a lot of cursing, I managed to recover the spring and detent and I set them aside.  I inspected the front takedown pin as well as the rear from the AR Stoner LPK and found that neither of them fit the Norinco lower.  Was it the kit or the lower that was out of spec?  I noticed a little paint and bled into the holes, so I scraped off the paint and it still didn’t fit.  I tested the pins on a lower I knew was spec – my Colt LE6920, and the pins slide right in.  It was the Norc lower that had slightly smaller holes.  So out came the file (didn’t take photos) and at this point, I was beyond caring since I paid so little for the lower.  I managed to remove enough material that the pins finally fit.  Cleaned it all up, coated the pins with CLP and test fit them before trying to install the take down spring and detent again.

The trigger assembly was pretty straight forward and the hammer and trigger pins fit perfectly.  The problem was the selector.  I was planning on using an AR Stoner ambi selector switch, which has worked for every lower I’ve built so far.  Inexpensive, and looks very close to the factory Colt ambi, except both tabs are the same length.  The problem?  I couldn’t put it into safe.  I wasn’t sure if it was the trigger from the AR Stoner LPK or if it was the lower, so I tried to Google it but didn’t find anything.  I did find once example of a Norinco CQ311 for sale where the owner had said that the rifle was stuck in fire and could not be put in safe.  So I decided to inspect the lower compared to a standard LE6920.  

The standard LE6920 lower selecter switch hole.

The Norinco CQ311 lower selector switch hole.  As you can seem part of the trigger is visible here, so at first I assumed the trigger was out of spec.  I was thinking about filing it down, but that was not happening.  It was pretty hard steel and I didn't have the right tools.  

Since I was at my wits end trying to remove material from the AR Stoner trigger with my crappy little files, I wondered what the factory Norinco CQ311 selector looked like.  I then remembered that my lower did come with a few parts and I wondered why the owner had included the selector and a few other bits.  Glad I didn’t throw it out, I dug out my spare parts box and found the factory selector and found a notch cut into the damn thing.  It appears that the location of the selector hole in the Norinco is lower, hence the notch in the selector to allow for more movement.  WTF, why bother???  They could have avoided this just by making the hole in the standard location.

I’d dug out the bag of spares that came with the lower but set it aside and continued on with my build.  

The factory Norinco selector worked fine and I was able to put it in safe.  Sucks I couldn't use my ambi selector, but at least this way I could put it on safe if I needed to.

Everything else just dropped right in until.........

I got to the carbine buffer tube.  The threads on my AR Stoner carbine buffer did not match the threads on the Norinco CQ311 lower.  More Googling led to next pleasant surprise about the Norinco CQ311, they used metric threads and I would be able to get maybe 2 threads in of the mil-spec carbine buffer tube (it didn’t matter if it was mil-spec or comm-spec) and that was it.  Where the hell was I going to get a metric threaded carbine buffer?  When I thought back to the Norinco CQ-A I had years ago, which was a carbine, I wondered if it had metric threads.  But then I remembered that it came with acomm-spec buffer tube and I was able to install a mil-spec buffer tube on it…which meant it would be incompatible to the CQ311.

I considered re-threading the lower to accept a standard mil-spec buffer tube, or even just forcing it on, but then I decided to try one of my rifle length receiver extensions.  Still no go.  I then noticed the A2 stock that came with the lower.  One of the reasons I bought the lower was because it came with an A2 stock that was probably worth more alone than what I paid for the entire package.  Anyway, the A2 stock that came with it had a receiver extension in it, so for $hits and giggles, I decided to try it and it spun right on.  I guess it must have been the factory CQ311 receiver extension, and I didn’t remember reading anywhere that the CQ311 with the A1 lower ever came in a carbine configuration.  

Of course it required a 13mm wrench to tighten it on, lol!

I tried to fit my old A1 stock that I’d purchased ages ago, but it didn’t fit.  It never fit any of my other A2 received extensions so I’ll have to go into it one of these days and sand out some of the material.  It might have changed shape internally over the years, or maybe absorbed some moisture or oil and the material expanded or something.  Either way, I didn’t bother with it this time around.

The rest of the stock assembly went on just fine without a hitch and the rear take down went in fine after I had previously sanded out the non-spec hole.

Surprisingly, the buttstock screw was the same spec as a standard A2 stock.  Weird.

Of course, this build would not be complete with at least one more problem.  One that I have yet to resolve, the grip screw.  The lower did not come with a grip screw, and the one from my LPK did not fit.  Nor did any of the other standard grip screws I had from my bag of A2 grips.  It turns out the standard size grip screw is 1/4x28 thread pitch and Norinco decided to not go with this screw size.  Goddamn Fukking communists, lol! 

I did a little more reading and it turns out that it is probably a metric screw size, however no information was available for the exact metric thread pitch.  I went to Home Depot and brought home and assortment of metric and imperial screws.  1/4x28 didn’t fit and the next size down was 1/4x20 and it didn’t fit.  I tried a standard M5 screw and it slipped right through.  I was able to get two turns with a standard M6-1.0mm (what seems to be the standard at the local hardware stores) but eventually it did not go further in. 

I’ve since learned that that metric screws, particularly M6 screws come in M6-1.0mm, which seems to be the most popular, then there are M6-0.5mm and M6-0.75mm.  I called all the local fastener shops in town and no one carried anything beyond M6-1.0mm.  There was a shop in the US that had M6-0.75mm for $4.50 USD each but charged $25 shipping.  I found an M6-0.75mm on Fleabay for $2.50 shipped, so I ordered one.  I couldn’t find an M6-0.5mm.   Anyway, the wait begins as it’s coming from China so it will probably take two months to get here. 

So, to summarize, the Norinco CQ-311 lower is a complete pain in the dick to deal with.  Most standard AR lower parts will fit, keep in mind the issues I ran into. 

My example had holes for the takedown pins that did not fit standard size takedown pins and had to be filed a bit to accept them.  I’m not talking a huge margin here, but some filing was required, it’s not like I had to get the drill press out and hog it out, just a bit of filing and the pins eventually dropped in. 

The fire control switch appears to be located lower in the receiver compared to the standard.  This requires you to either notch the selector switch to allow it to go into safe, or remove material from the trigger to allow a standard selector to switch into safe.  Or, just use the selector that comes with the CQ-311.

The receiver extension is metric, so a standard AR carbine buffer tube or rifle length receiver extension will not fit unless it miraculously has metric threads. 

Lastly, the grip screw.  It is not the standard 1/4x28 sizing, it’s metric, and likely M6-0.75mm or even M6-0.50mm.  I still have to figure that out and a possible solution is shipping from China and should be here in another month, lol!

Still, despite all of this, there aren’t that many other options for A1 lowers in Canada.  I know there are a couple of large takedown-pin Colts out there, and I suppose I can source the adapter for it, but this came along for a great price….and now I know why, lol!