So the common explanation seems to be "for strength". But I'm not sure that's necessarily it. Afterall Chinese AKs were meant to be disposable guns for disposable troops, how strong do they really need to be for a soldier that would have been unlikely to make it past their first battle?

I had an opportunity to take a set of calipers to various types of AK receivers (Type 3 milled, Russian pattern stamped and Chinese pattern stamped) and guess what the receiver walls on a milled AK measure at? 1.5mm.

I suspect the Chinese did it just for simplicity of manufacture. Alot of parts inside the AK are kind of designed around that original 1.5mm receiver wall. The way the FCG pins and parts and bolt carrier fit is specifically designed with that 1.5mm in mind. If they had done a simple "Chinese pattern" stamping but just 1mm thick, it would need all new parts specifically sized for that 1mm receiver that would not be cross compatible with the old milled receivers.
The Russians got around this with all those little detailed extra stampings (the X,Y around the FCG pin holes, the little stepdown in the top bolt carrier rails, and other areas) which when you measure from the outside surface of the receiver, to the inside surface of those stampings measure out to *drumroll*  effectively 1.5mm. But all that requires more complex stamping. So the Chinese figured why bother with all that? Just make the whole thing out of a simple 1.5mm sheet like the old milled receivers and call it a day. Notice how RPK and Yugo receivers don't have those little details. Because they don't need them, because the whole thing is already 1.5mm.

Basically the Russians switched to stamping, not just for simpler, faster production but also to reduce weight. So the AKM was completely redesigned from the old Type 3 pattern to lighten everything. The barrel, the bolt and carrier, the front sight base, the gas block, the top cover (which also has those little step downs around the edges where it touches the receiver sides to maintain the same effective dimension and fit as the "slab sided" Type 3 top cover). Everything was put on a diet. They were willing to go through all that to make the gun lighter while still allowing it to use older AK-47 parts in a pinch if needed.
The Chinese didn't care about reducing weight, they just wanted to make the receiver cheaper and simpler to produce since it's kind of the most complex and time consuming part of the whole gun to make. Which explains why they kept the rest of the gun the same as the old milled versions. Because they were already set up to make those parts and making them slimmer and lighter wouldn't have really made them any faster or cheaper to make (in the case of the bolt and carrier, it would actually increase machining steps), so not really worth the effort of changing over. I think not having to worry so much about great heat treatment was a bonus but not the main concern.

Now the RPK and Yugo AKs DID go with 1.5mm receivers for strength. The RPK for all the extra full-auto fire it was expected to provide. And the Yugo AKs to withstand launching rifle grenades. Which is exemplified by the fact that not ALL Yugo AKs got 1.5mm RPK receivers. Underfolders and various other models not equipped or intended to launch grenades got 1mm receivers (Sometimes. They seemed to kind of switch back and forth whenever they came up with a new variant. I guess they did that on earlier stamped underfolders for weight and on later ones just said "Meh screw it, not worth it, keep it simple and make them all use the same 1.5mm stamping).

That's my theory atleast. What do you all think?

I'm of the unpopular opinion that Chinese AKs are by and large garbage compared to most Euro AKs of the same era.

Every one I've looked at has been roughly machined, tooling marks everywhere, bluing that rusts easily, soft wood that scratches, dents if you look at it wrong, etc. Just not a fan.

If you want my take, they were made in 1.5mm steel because their sheet metal was crap quality, and their heat treatment processes probably sucked, but if it was thicker it wouldn't matter, and the Chinese always had a lot of steel to throw at things - just not great steel.

That being said I'd love to have a PSA spiker as an example of a Chinese AK that wasn't built with poor borderline slave labor

Yeah, Chinese steel is crap, ask any welder that has worked with it.

Good points. The Chinese probably wondered why mess with something that already works. I do like their AKs, contrary to what seems to be the popular opinion. My sole Chinese example is nicely machined and finished, but I can see any country's reason for skimping on the machining...is it necessary for the function of the gun? No, so why spend extra time and effort to make them look good? They only have to function reliably and you can spend the time saved to make more.
Of course, you throw in some historical cultural pride and see that some of the European countries really made the extra effort to produce very nice AKs. On the other hand, if you want to see really poor quality that makes the rest of the world's AKs look like Swiss watches, just look at the Egyptian AKs. Not only is their machining horrible rough, but their finishes rival old Sears latex paint.

I want to add the Russians always intended the AK to be stamped, but couldn't solve the problem of warped receivers for mass production. They had so many rejects from the heat treating and welding that they had to do something, so they switched - temporarily - to the milled receivers which they had a lot of experience in manufacturing. The original AK was, in fact, made with a stamped receiver. When the Russians co-manufactured the milled original AKs, they made no model distinction between the stamped and milled versions and actually made the original stamped versions through 1951, even though the milled receivers were ready for production back in 1949.

The US commercial AK, particularly the Poly Tech were Beautifully made. But from what I’ve read, the current Chinese AKs sent to Africa are hot garbage. It would be interesting to compare the two.

I thought it was common knowledge the Chinese AK was designed after a milled AK and not the AKM....

I heard the same even way back. If you're in some wartorn shithole and AKs are being handed out, you generally want anything other than a Chinese one if you get the choice. But China is generally willing to build to whatever standard you're willing to pay for.
An African warlord? Probably not going to be too picky about quality. And not willing to pay anymore than they have to.
The US commercial market? Considerably more picky. So they'll give it a little extra buff and polish for you.



And yet people seem to sing praises of old Norinco 1911 and M14 clones. The old Pardner Pump 870 clones are often touted as having better steel than the Remington made 870s of the time.

I don't think weldability is a meaningful indicator of how "good" a particular steel is. Plenty of great steels suck to weld. Because welding is not what they were designed for. Do you care if your knife blade is easy to weld?

Sure. The fact that they kept the entire front end of the AK-47 rather than updating to the AKM pattern like practically everyone else did makes that obvious.

I just figured this was an interesting detail that I've never seen mentioned about WHY they did that specifically. It's not as if they didn't have access to AKMs to copy off of, even if the Soviets weren't willing to supply them directly.

This WAS the popular opinion back in the late 80s and early 90s.  Only when the European models became less and less common did the Chinese grow more popular.

Now you have internet self proclaimed "Experts" talking about how superior the Chinese AKs are...

There was no YT back then, but if there had been, it would have been filled with videos dog cussing the Chinese AKs

Also, I love my PSA Spiker!

+1 that's what Vladimir O. of Kalashnikov Concern claimed: https://www.thefirearmblog.com/blog/2023/02/14/chinese-aks-controversial-kalashnikov-variant-part-2-type-56-took-world/

we considered them throw away guns and beat them like redheaded step children whenever we went to the range.

For the record, I don't honestly consider them crap myself, I just don't consider them superior in any way.
However, the popular opinion back in the day was that they were the bottom of the barrel AKs

I just like the way they look. They have this perfect mix of AKM and AK47 features. Except for the spike, I don't really care for the spike. I'll pick up a PSA soon as I can. Now if they make an underfolder, oh-lala.

You can’t just say that they had shitty quality steel, you also to keep in mind that they went thru a period where they actively killed or re-educated anyone with an education, and then got the stupid idea that they could melt down all their scrap steel in backyard furnaces, and somehow turn it into high quality alloys….yeah, nope!  So they trashed their brainpower, then trashed all their metal.  Real smart, as communists are wont to be.  (Russians did similar thinking they could apply communist ideas to plant biology- marxists are fucking dumb).  

Anyhow, coming off of all that, now they are building AK’s.  Their alloying capability might be a bit questionable, their heat treating was likely questionable, and they knew an AKM style receiver needed a good heat treat and raised reinforcements, but they no longer had Soviet assistance, as they had split ways by then, so they didn’t know what exactly the specs were that the Soviets had designed the 1mm receiver around.  

So the safe and smart answer was to make the sheet metal thicker so that they could avoid concerns with weaker metal, and not worry about needing the reinforcement areas to get it to the same side width internally.  It wasn’t just that the receiver was made to re-use milled AK internals, because even the Soviets pretty much did that with their AKM design.  

By going to 1.5mm, they eliminated worries about a more complicated stamping, they reused the milled AK internals designs (same as the Soviets did), and they alleviated any concerns about their questionable steel, the issue of which was still fresh in their minds.

It was a smart design move- saved development time and testing, simplified the stamping, and the weight addition was negligible.  Good engineering all around, considering their circumstances.

Now today, we still see substandard chinese steel pretty commonly, I have seen it myself.  But we have also seen what happens when a 1.5mm receiver is not heat treated (B-west’s, they wore out prematurely).  And there are a lot of US made homebuilts which won’t stand up to long term use due to incorrect (or none at all) heat treating of 1mm receiver flats.  So long term, the decision to go 1.5mm for the chinese AK was the correct one.

Everyone commenting on the fit/finish….take a look at a Colt.  Something made for war, at a certain price point, is seldom going to be made for appearances…. I think we can all agree chinese AK’s work pretty dang well, which was what they were going for.  The Polytech Legend series being the ones actually made for US consumer tastes, hence why they are nicer fit/finish, and actually have spring loaded firing pins.

Chinese order of importance for AKs:

1. Reliable
2. Inexpensive
3. Easy to manufacture
.
.
.
.
100. Looks good.

I stumbled into this knowing nothing about AK's.

This doesn't mean anything to machined parts but 16ga carbon steel sheet is .0598 or .06 which is 1.5mm. IT is one of the most commonly available materials.

Gauge Inches MM
7 .1793 4.554
8 .1644 4.175
9 .1495 3.797
10 .1345 3.416
11 .1196 3.038
12 .1046 2.656
14 .0747 1.897
16 .0598 1.518
18 .0478 1.214
20 .0359 .911
22 .0299 .759
24 .0239 .607
26 .0179 .454
28 .0149 .378

I always liked Chinese rifles, only bad thing is after you get done shooting them, an hour later you want to shoot again.

What do you all think?

That is a good assumption, or theory.  I could see it being true.  Another possibility could be the materials used.  It might be that there was a cheaper steel that they could use to make the reciever, and 1.5 as opposed to 1mm made up the difference.  Conversely, they might have chosen a "better" alloy for the barrels, which might explain why the barrel journals are smaller than European AKs.

I lean toward usage of materials they had, and were willing to allot.  One thing is for sure, it made a great AK.