The routing for the bayonet slot on 49s I have seen refurbed with laminates kind of looks weird to me. Almost chiseled looking at the end of the slot...which it might have been, the amount of work needed to slim them down to the 49 ferrule seems tedious vs just upgrading the entire thing to fit the new standards....yet it some cases, it appears as if they did.
I just can't wrap my head around them replacing one part to make up for it no longer being compliant with the current norm when refurbishing....at least with the haphazard refurbing process that has parts getting xxxed out or completely replaced. There are enough little pains in the backside between 49 and 50 that would seem to warrant an entire barrel replacement vs. doing half the job, and having to deal with keeping the original gas block and front sight block together....which often does not appear to be the case during refurb.
The idea that somewhere in 50, a 49 would need to be reworked at all seems laughable to me. I am leaning more and more that the spike/blade transition actually happened across 49 and 50 and both were made concurrently for a while...and that at refurb, perhaps some of them just got special attention. As fastidious as they seemed to be with refurbing, you would think all early features would have been eliminated before we ever got to see them...but, they didn't....why? The fact that a seemingly verifiable spiker 50 exists seems to lend towards what I am saying. Right?
I also think we never will really get to the bottom of the early Russian debacle...but it sure is fun thinking about it. My parents were born in 49....there is very likely nobody still alive with first hand knowledge what on earth they did. I sure am glad I dove in to my first Russian being so worthy of discussing though...everything else besides the first couple years almost seems boring. I think once I pick up a 45 degree 50...I might be done, unless a pretty Izzy comes up....I am running out of wall space to hang them. The guitar collection is getting nervous....they are almost outnumbered.
Bottom line, the differences between the pin placement on the 49 to early 50 on the FSB is an issue...the top vs. bottom pinned stock ferrules also is an issue....as is the slender stock needed for the spike and it's original tiny stock ferrule...which in no way resembles the later Chinese spike ferrule...yet another issue. I think there was a lot more development during this period than we will ever be able to address for certain...I enjoy trying to make sense of it nonetheless.