The Thompson Contender Pistol was among the first firearms produced by the Thompson Center Arms in the 1960s. The Contender (whose production began in 1967 and lasted until the 1990s) was a designed by Warren Center as a pistol which allowed the user to change the barrel and weight of trigger pull.
The Contender's most striking feature was its overall appearance. The grip was shaped to better fit the shooter's hand, with grooves cut to accommodate their fingers. The frame had a sweeping, elegant shape to it, while the trigger guard continued the sweep, bringing it to a point at the underside of the guard. Above the barrel (which was octagonal in shape) a rail supported the sights, an innovation which meant that the barrel could be removed without affecting any other major features of the pistol. The receiver was engraved with a cougar to add to the striking appearance.
Mechanically speaking, the Contender also had several other unique quirks to compliment it's aesthetics. The barrel was hinged to allow the spent cartridge to be removed (via an extractor) and allow the new cartridge to be loaded. The fore-end of the Contender could be removed in order to allow access to the hinge pin. Once this pin was removed the barrel could then be removed and changed for another of different calibre. This could be achieved as the frame and mechanics contained no cartridge specific design elements.
The Contender was also fitted with two firing pins (one for centrefire and the other for rimfire cartridges) with hammer designed to be adjustable to strike either of the pins. The trade-off of this design was that the hammer had no default "Safe" position, while the hammer would be adjusted to strike either pin using a screwdriver (although later models would use a variety of different selectors including buttons; slides, and switches each with a modified hammer). The trigger was, likewise, adjustable which allowed the shooter to adjust it from a heavy pull to a hair trigger.
The Contender was designed to use a variety of cartridges, largely due to the fact that none of the internal parts were specifically designed for one cartridge. Therefore the bore of the barrel would dictate which calibre could be used, although Thompson would limit the potential cartridges to those whose pressure could not exceed 48,000 CUP.
The Contender's near limitless customization regarding cartridges meant that it was a popular firearm for wildcatters, whom produce customized cartridges for firearms. The Contender can also cope with firing the .45-70 Government cartridge (a rifle cartridge from the 1870s) because it is a blackpowder cartridge which produces lower pressures than equivalent modern day rifle cartridges.
The Contender was a popular firearm for Thompson, effectively helping them to get off of the ground. The major cause for this popularity was the fact that the Contender could effectively fire any cartridge (so long as it did not exert a pressure of over 48,000 CUP on the internal parts) as the barrel could be changed. Of course only barrels made for the Contender Pistol would fit the frame but the fact remains that any Contender barrel could fit any Contender frame.
The Contender's success spawned other break action designs from Thompson, particularly designs based on the Contender. Once the Contender was withdrawn from production in the 1990s the Thompson Encore was released as an improved version of the Contender (as well as to celebrate the design). Later the Contender G2 was released (the second generation of the Contender) with a wealth of modifications to the design, and remains in production to this day.