I have recently seen a shotgun which looks new and on the left side of the receiver it has the H&R 1871, mfg in Ilion,NY stampings but in front of the mfg line it has a QR code diagram etched/stamped into the receiver also. Like you may have seen on the Remington R51 or RM380 pistols.
I have never seen this in any NEF or H&R firearm.
I have collected a few lately and have seen many over the years but this is the first time I have seen this on any of the NEF/H&R firearms. This one has a laminated stock set which looks good. The only other shotgun I have seen with the same stock set is a 12 gauge which is very similar to this one but without the QR code.