Ammunition
Some authorities have recommended against the use of higher-pressure +P-rated .38 Special cartridges in aluminum-framed Colt revolvers, as the Cobra was designed well before the advent of such ammunition. In the owners' manual accompanying some post-1972 Cobra revolvers, Colt recommended the use of +P ammunition for 2nd Model Cobra frames only, with the stipulation that the gun be returned to the factory for inspection every 1,000 rounds (compared with a 2,000-3,000 round interval for the 2nd Model steel-framed Detective Special). The Cobra should never be fired with extreme-pressure +P+ ammunition.
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