Mossberg More Gun For The Money; The History of O.F. Mossberg & Sons, Inc. by Victor Havlin and Cheryl Havlin
The 44US target trainer was designed exclusively for the war department, and intended solely for use by U.S. troops. OFM had filled orders for almost 58,000 units from 1943-1945, with another 19,000-plus scheduled but not shipped due to contract cut-backs and cancellations near the end of the war.
The 44US was adapted from the pre-war 44B model, and , like the 42MB, the adaptations were mostly made to keep costs down. Ordnance wanted an accurate, dependable, heavy-barreled trainer, and sacrificed some cosmetic detail to make it affordable. While the 44B featured a deluxe, genuine walnut stock with long beavertail and cheek piece, the 44US stock was plain, usually birch with walnut finish. Gone also was the four-position front swivel plate, and both front and rear swivels were fixed, rather than detachable, on the 44US. The plain S-122 front sight was requested, and the government wanted a new receiver peep sight - rejecting the No.4. While Harold Mossberg was busy designing this new sight for the United Stated, the first batrch of 14,500went out with Lyman 57MS receiver peeps.
The United States Armed Forces continued to train with the Mossberg 44US target .22 after the war, using supplies in Ordnance from these contracts, and some rifles may be found with branch markings, such as U.S. Navy and some Coast Guard trainers stamped U.S.C.G. The navy continued its training with Mossberg target .22s for over four decades, commissioning a Model 144US in later contracts (1949-1960) and used both in active service training and at Naval Junior ROTC academies. The United States Air Force and U.S. Army also acquired the later 144US, and as late as 1989, Rock Island Arsenal reported a total of 3,552 of these models in current stock. Approximately 2,500 of these were still in active use, primarily as trainers. Government nomenclature designates these rifles as either "M13" grade (training rifle) or "M12" grade (match use).
If interested I can give a breakdown by contracts (date, contract, quantity, Unist $, and serial number range).