BrentD, it is a .22 LR. The Model 37 was Remingtons answer to the Winchester 52. When introduced in 1937 it was a better rifle than the 52 of the time and it really gained quite a following. Winchester was forced to make some changes to improve the 52, particularly the trigger, to remain competitive. These changes resulted in the 52C model which was the first with the micro-motion trigger. One interesting fact about the 37 is that there is not a single stamped part on the entire gun. And this includes the magazine.
John
