I have owned a couple of the 1600 series rifles - current one is the short barrel carbine with Monte Carlo on the butt stock - the Model 4100 - in 7x57. Same issue with twist rate - for whatever reason is 1-12, so perhaps were thinking to use shorter bullets like a round nose 150 grain? Early version like this one have steel bottom metal - the tongue is narrower; later versions were made of some kind of alloy, maybe even aluminum - the tongue is wider, so that is a consideration, if a replacement stock is to be purchased. The Swede's were pretty fussy about the "proof testing" business, so if Husqvarna chambered it in 9.3x62, it will safely handle CIP level 9.3x62 pressures. If someone else screwed on a 9.3x62 barrel, without proof testing, then that might be different. If it was made prior to about 1968, it will have the serial number on the barrel, not on the receiver - at least not visible on the receiver when rifle is assembled.