The major factor of course is the lengthened magazine starting with the 900K guns. I can believe a .243 could be squeezed into the 700K guns but not a .308 180 grainer.
The description did say "proto-type shop." Probably not just any 700k rec'r./rifle.
Yup. Boy I'd love to get a closeup look at that!
How about this?...
After the move to Chicopee things were humming along nicely @ s.n. 500,000 and up.
In the early to mid 50's R&D begins work on other calibers that require a longer magazine.
R&D fabricates a quantity of peaces with a longer magazine, sequentially numbers them (~700,000) and begins work, evaluation, testing, etc.
As the designs are becoming mature and being formalized in preparation for production release Management decides to create a gap in serial numbers for shipment to differentiate this major design change and jumps to 900,000.
Or possibly a few 700k rifles were produced before the 900k change or a few R&D rifles leaked to the public or both. ??
I guess we have the rifles at this point, just not insight to understanding the whys and hows of Savage operations at the time.
