hello all, Hoping for some help with this one.. I am fairly certain its a Norwegian Krag, it is chambered in 6.5x55 but not marked anywhere i can find

This was my grandfathers firearm and i am quite sure it is not a "sporterized" krag. I believe it came this way.. the only other one i've seen is on some auction site and is mislabeled as a "sporterized" version.. would love to see if anyone here has some info they can share.

Markings on the Firearm

- Letters AA are on the switch that controls if you are pulling rounds from the trap
- Markings D and B are under the rear sight. as well as some other marking in between them that i do not know what it is.
- there is a T marked in the side of the barrel
-10221 in the metal butt plate
- 20752 stamped into the barrel with other hallmark markings.
-1918 stamped on the top of the barrel below the

other unique piece is the trigger guard has a hole on the front side of it..

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