jeans I wrote about last time.
The bottomline is basically that even though they looked so different compared to the 1967 505s and 1966 501s, which should be the closest relatives, they could still be a reproduction of how a pair of 1966 505s looked and not just something Levi's made up.
I still think it's weird, but if that's how it really was, then that is of course the way they should do it!
What Paul had to say:
Only had VERY quick look, and must admit I haven't looked at LVC 505 jeans closely. But the weight and arcuate look right. Sanforized jeans are always 10% heavier, because they've shrunk by 10 per cent. And that shallow 66 arcuate is just one from a range of shapes LVC chose for their 66 jeans, so it is perfeclty logical they should use a deeper shape for another model.
I've just checked out some of the info from Japanese LVC i have, and the arcuate looks identical to the Japanese version from 2001 or so. 505s in general do seem to have a different pocket shape - it's more square, less splayed. But that slightly tapered, curved stitching on yours does look weird - I haven't seen it before.
Yes, arcuate stitchings did vary from factory to factory. According to one guy I spoke to who worked for Levi's from the 70s through the 80s, as well as on the very early LVC, it's simply because the tooling became worn. Even when you see shapes changing in the early 80s jeans, it's because they were trying to get back to a more 'classic' shape.
To me, the very flat arcuate LVC generally use in their 60s jeans looks TOO flat - almost an exaggeration, perhaps to make the different models look more distinct, although I'm sure that shape will have appeared from one of their factories.