It's a military Mauser that was sporterized (turned into a hunting rifle) This was done a lot after the war.
That crack in the stock above the pistol grip needs to be addressed as it will get worse from recoil. Thank your father for his service.
Unfortunately he passed way too young in 1985, he was in the 101st airborne F company327th Glider infantry regiment, 2 purple hearts and the bronze star for service from June 6 1944 to May 8 1946, for courage in the Normandy campaign, The airborne assault on Holland in Sept of 1944, and the defense of the key city of Bastogne Belgium from the 19th of Dec till the 27th of Dec. he spent almost a year in England prepping for D-day.
My father has the guy sitting on his shoulders
Mohawks right before D-day