I recently inherited a 38 special mod 10-4 and I was curious as to what/any information I can find.

Welcome to the forum.

It was named the .38 Special Military and Police revolver and traces its lineage back to 1899. Model numbers were assigned in 1957 when the gun became the Model 10. The number after the dash (-) is an engineering change level. Normally, S&W assigned engineering changes when they made evolutionary improvements, but the Model 10 is one of the cases where they used the change level to designate unique variations and several engineering levels were produced concurrently. The 10-1 had a heavy barrel. I assume they made the distinction because the front of the frame had a different taper to accommodate the differing barrel profiles. The 10-2 (standard tapered barrel) and 10-3 (heavy barrel) indicated the change from right to left hand threads on the ejector rod. The 10-4 change eliminated the triggerguard screw on the standard weight barrel version. It was only in production for a short time in the early 1960's, when it was replaced with the 10-5 that had wider sights. The 10-6 change eliminated the triggerguard screw on the heavy barrel.

The 10-5 is the most common version and a collector looking to fill a void in his collection might pay a bit of a premium for a 10-4, especially if it's in excellent condition. The Model 10's are great guns, but they're very common and a lot of people wouldn't care about the specifics.

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