Maybe Roy doesn't have an "explanation" but I do...
We see the RM box numbers to the gun so it is most likely original to this gun. It is numbered in the same fashion as the pre war 357s. As for the barrel having the LERK cutout, I believe this to be because there were left over 8 3/8 barrels from the transition models. In the transition 357s, IIRC, the 8 3/8 barrel is the rarest length, or next to the rarest. For the factory to have extra barrels makes sense, because they probably anticipated better sales of the 8 3/8 barrel. In the pre war years, with the RM and the NRM, the 8 3/4 (there was also an 8 3/8 available) barrel was one of the scarcer lengths, and out of the standard lengths (4, 5, 6, 6.5, 8 3/4), it was one of the more rare ones. This makes for a likely surplus of 8 3/4 RM/NRM boxes which were still at the factory in the post war years.
Roy claims that 4286 of the pre 27s were manufactured by the time Kris's revolver shipped. He uses this as a support that the older barrel and older box are out of place. I believe this to be short sighted because despite me believing his claim, this fact is not relevant to the barrel and box for Kris's gun, which are unique to each other. The fact that the factory was pumping out 6in 1950 model 357s says nothing about the sales of the 8 3/8 models. What percentage of the 4286 1950 357s that were made by shipment of this revolver were long barrel guns? I bet a small amount of that 4286. If there was a small amount made by the time of shipment, this would support that the older parts (and boxes) were still being used up. We all know S&W didn't throw away good parts, or boxes.
In conclusion, my opinion is that the box and barrel were both around due to lower than expected sales (for 8 3/8 357s) in both the pre war years and the early post war years. I also believe that by 1951, a small percentage of the total production for 357s was for 8 3/8 357s. Keep in mind that the 8 3/4 in RM boxes would only accompany 8 3/8 post war 357s. The factory would not place a 4in 357 in a long RM box, so the boxes sitting around waiting makes perfect sense. Aside from all of this, the barrel numbers to the gun anyways.
Despite the content of the letter, I still like the gun and I still believe it is all correct.
I think the "ship to" is a winner too. Too bad the letter did not have more sight information. But, like you said, hopefully at some point you can find that out thru the SWHF paperwork.
You must be pretty talented - I have enough trouble just shooting from the hip...
