The Ithaca 37 is a pump-action shotgun made in large numbers for the civilian, military, and police markets. It utilizes a novel combination ejection/loading port on the bottom of the gun which leaves the sides closed to the elements. In addition, the outline of the gun is clean. Finally, since shells load and eject from the bottom, operation of the gun is equally convenient for both right and left hand shooters. This makes the gun popular with left-handed shooters.
The Ithaca 37 is based on a 1915 design by the famous firearms designers John Browning and John Pedersen, initially marketed as the Remington Model 17. The Model 17 was a 20-gauge of trim proportions, which Browning and Pedersen later redesigned and refined into the popular side-ejecting Remington Model 31. That gun would eventually be replaced in production by the less expensive Remington 870 which is still produced to this day.
Following the First World War, the Ithaca Gun Company was searching for a pump-action shotgun to produce, primarily to compete with the ubiquitous Winchester Model 1912. They settled on waiting for Remington Model 17 patents to expire. After gearing for production of the Ithaca Model 33, they discovered more Pedersen patents that would not expire until 1937; along with the introduction date, they changed the model designation from 33 to 37.
With the depression dragging on and war looming on the horizon, it was possibly the worst time to introduce a sporting arm. Many sporting arms ceased production entirely during the same period. While Ithaca did produce some shotguns for military use during the war, they also produced M1911 pistols and M3 Grease Guns.
After WW-II, Ithaca resumed production of the Model 37. Made in many different models, the Ithaca 37 has the longest production run for a pump-action shotgun in history, surpassing that of the Winchester Model 12 that had originally inspired Ithaca to produce pump-action shotguns. Ithaca has suffered many setbacks in its history, changing hands numerous times. At one time, the Ithaca 37 was renamed the Model 87, although it was soon changed back in one of many ownership changes. Production paused in 2005 when Ithaca once again changed hands. Production has resumed in Ohio.
The largest single user outside the US Military is the Los Angeles Police Department. Along with the Los Angeles County Sheriff's Department, numerous other users include military, police, security agencies, and prisons. The Ithaca 37 was a popular choice among civilians for both sport and personal protection. With higher prices for new Ithacas and decreasing availability compared to the Mossberg 500 and Remington 870, use of the Ithaca 37 continues to decline. Interestingly, Ithaca's loss of market share was hastened by competition from a copy of the shotgun. Chinese copies of the Ithaca 37 have been imported recently. Additionally, the supply of used civilian and departmental shotguns has been a steady competitor.
Loading the Ithaca 37 involves inserting shells of the proper gauge through the loading/ejection port and pushing them forward into the magazine until retained by the shell stop. The slide release is pressed and the slide retracted completely then pushed forward. Pulling the trigger fires the gun and releases the slide for reloading. On most models, holding the trigger down allows the gun to fire the instant a new round is cycled into the chamber without requiring the trigger to be released, a process known as slamfire. Otherwise, the model 37 operates in much the same way as other pump-action shotguns.
There are versions too numerous to mention. Here are some popular models:
- S-prefix: were manufactured for a 1962 United States military contract. S-prefixed serial numbers ran from approximately 1,000 to 23,000 with "U.S." on the receiver and "P" proof markings on the barrel and receiver. The guns have a Parkerized finish with 20 inches (51 cm) barrel and plain stocks with plastic butt plates and no sling swivels. A few later contracts produced smaller numbers of guns with sling swivels and serial numbers in the high 900,000 range. Some had "duckbill spreader" shot diverters for use by United States Navy SEALs. Others were fitted with a ventilated handguard and bayonet adopter. New bayonets were manufactured by General Cutlery, Inc. and Canada Arsenal, Ltd.
- Ultralite: an aluminum receiver variation.
- Deerslayer: a version with a shortened barrel and rifle-style sighting system.
- DSPS: for Deerslayer Police Special. A military and police version
- Stakeout: short version with 13 inches (330 mm) barrel and pistol grip stock, which was notable for being the signature weapon for Ricardo Tubbs, Philip Michael Thomas' character on Miami Vice as well as being the secondary weapon of Dwayne Hicks in Aliens (film) with the words "no fate" carved into the top, a reference to Michael Biehn's role in The Terminator.
- 28 Gauge: 28 gauge model built on traditional size 28 gauge receiver.
- Defense: an affordable 12 gauge model built for home defense purposes. 18.5" barrel with 5-round capacity or 20" barrel with 8-round capacity.
The Argentine firm Industrias Marcati manufactured the Ithaca 37 under licence as the Bataan Modelo 71.
Browning Arms also started to manufacturing its own version called BPS (Browning Pump Shotgun) in 1977. Browning started with 12 gauge only, but BPS now come in 10, 16, 20, 28 and .410 as well as 12.