OK, well IDK about the case of these parts, but there are oodles of AR parts coming in from China, and have been for the last ??? 10 ??? years? Of course more and more as time goes on.
I have seen some of these come through here that looked good to the eye, but if you knew the part, and what to look for, they were absolutely junk!
Not just that, but as you know - if you bought it from China, it's yours, good or bad.
2 Tiers up from me got in a boat load of [plastic] lowers. But as the mfgr tapped the thread for the buffer tube, the part flexed away from the tap and resulted in an oversized threaded hole.* The customer had already bought issued serial numbers for these lowers, and if they scrap them, they need to pay again to have them annulled. (as the story was told to me)
So, they asked me for a cpl thousand (?) tubes that had an oversized thread to match.
I sent them back some samples that had a pitch in the ballpark of their needs, but this would require that we make nuts that were the same oversize, but that's easy.... BUT, the big issue was that the keyed worsher that slips over the thread wouldn't fit. (oh yeah....)
So then they ask me if I can make the thread pitch O/S but still make the worshers fit?
Well, yeah, I guess .....
So then we ran them O/S and then clipped the tops of the threads after being rolled to fit the worsher hole.
Then they came back and complained about the threads being flat and looking bad.
Apparently there is only accountants and assembly technicians that work at this place. Not someone that actually understand the limitations of physics?
We did not end up producing the parts, which made me feel a bit better - knowing that down the road someone might want to replace the butt-stock assy for whatever reason, only to find out that the lower was not built to "interchangeable parts" tollerancing.
But then - if you bought a plastic gun ....
* and would seem to have to be out of alignment as well, but I cannot confirm that.
But I just don't know how it couldn't be...
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Another that comes to mind right off was some Buffer Tubes that came in from China. These parts looked NICE! They had a very nice plate job on them, and had the MFGR (well, the assembling and retailing company anyway) it had their name all laser etched on them. Looked REALLY nice.
But of the few samples that I was given, I found that the tube thickness under the keyway slot was WAY too thin. It is s'posed to be .050-.055 thick. These were down to .012 and you could see that the web was so thin that they were already starting to buckle and wave, and they hadn't even been assembled yet!
Well sure, we're not perfect here either. We could prolly screw them up too. But the difference is that the customer should never see that part, and if they doo, they would Shirley be asking for replacement parts. But if they bought them from Cjina, they will have to try to make doo with what they have - if at all possible.
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Point being - some folks would pay extra for parts known to have been made State-side.
(some)
Are these $70 units local?
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Think Snow Eh!
Ox