Hello, E.M. Betting and welcome!

I searched on the internet for serial numbers for the Norwegian Krag and found this website:

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Your number 151157 seems to be for a model M/1894 rifle made in 1922.

But near the bottom of the webpage is a picture of a target rifle similar to yours.  The caption reads in English:
"The rifle M/25 was produced from 1925 to 1950 in 2274 specimens, while the version M/30 from 1936 to 1951, a total of 854."

Perhaps your target rifle was made from an M/1894 military rifle?

There are people on this forum who know a lot about Norwegian Krags so we should hear from them soon.