JTC, very interesting to know that some double barrels weren't soft soldered. I have seen a couple soft solder guns that someone attempted to hot tank blue, makes a real mess.
Tom, I have to apologize for not giving you thoughts on the tang safety as a possible factory modification more thought & research, I just thought if it were a tang safety they would say that and they would not use an aftermarket kit, and I had not seen anything similar from Savage -
After thinking about it over night I believe the after market tang safety is what Savage offered as a left handed $9.25 fix in 1949. I believe that is about when some of these kits were offered. I have seen over a dozen of these conversions and all looked factory done. Tom
I still think it more probable it was some sort of modification using a part similar to the one Numrich but while looking for a patent for the ambidextrous safety (which I did not find) I found a couple for a tang safety's, one that was assigned to Savage Arms, so it certainly can't be ruled it out
This one is assigned to Savage Arms and looks similar to the kit you pictured, but it looks like this one replaced the existing lever safety and I think these kits might just have attached to it. This one shows an added piece behind the tang attached to the wood similar to the kit -
Full patentUS02465699 This one is not assigned to Savage and does not show a separate piece added behind the upper tang (but the picture shows a tang that looks like it might be longer than normal). It does look like it attaches to the existing lever safety though.
Full Patent US02478892 Savage had must have looked at using a tang safety on the 1899 very early, this is a C. A. Nelson patent filed in late 1916 -
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