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The Ruger Standard Model .22 auto was an instant success. By the day the operation had to spend the last dime of the original $50,000 investment with which the two partners began, there were 100 guns ready to leave the factory to fill prepaid orders (Ruger refused to cash any customers’ checks until the pistols were made). The first production pistols shipped in the fall of 1949. From that moment onward, Sturm, Ruger & Co. has been sustained with profit from sales, never borrowing a cent. Sturm died in November of 1951 from viral hepatitis, and Bill Ruger ordered the color of the company’s logo forever changed from red to black.
No sooner than the Standard Model .22 auto was on the market, new versions, variations, and small design modifications and refinements also began to be produced. The first major addition was the Mark I Target pistol, which was announced in December of 1950. It was mechanically the same as the Standard Model gun but had a tapered 6 7/8-inch barrel, a Patridge front sight blade undercut to reduce glare, a “Micro-adjustable†rear sight, and an improved trigger with stops to reduce slack and overtravel. In September of 1952, Ruger also introduced a Mark I Target Model with a 5 1/4-inch tapered barrel. It was manufactured only in limited quantities until 1957. Today it’s a collector’s item.
Next to appear (in late 1954) was a six-inch version of the fixed-sight Standard Model, otherwise exactly the same as the 4 3/4-inch gun (these two configurations are still offered as the “Standard†format today). The 5 1/2-inch Bull Barrel Mark I Target Model was introduced in 1963, and the bull-barrel style has since become the most popular of the target-sighted guns
Ruger decided to add a bolt lock to the gun so that the bolt would stay open after the last round in the magazine was fired. This lock would be actuated by the magazine follower button when it reached the
top of the magazine, and it would be on the left side of the frame for right-handed use. The original magazine button was on the wrong side. So when the time came to make new forming dies for the frame, they were changed. The new feature would appear as part of a comprehensive redesign and upgrade in 1982.
The new generation of Mark II pistols would have the same list of variations in terms of barrel styles and sight systems but also included several new mechanical features. There was the new bolt lock. There were twin scallops, or recesses, at the rear sides of the receiver to allow easier grasp of the ears of the bolt when cocking. There was a further redesign of the magazine, giving it a 10-round capacity instead of the previous nine. Most significantly, the safety was redesigned so that it locked only the sear instead of both bolt and sear. This allows the bolt to be pulled to the rear for visual inspection of the chamber and loading or unloading while the safety is engaged instead of requiring the safety to be taken off to inspect the chamber. Other improvements included a better designed trigger pivot retainer (a music wire spring instead of a lock washer), which makes it easier to disassemble and reassemble the gun.