Forget looking for "Pressure signs" with .38 Special, or any low pressure cartridge! You simply are not going to see any because nothing will show, absolutely nothing, until pressure levels are 200% or more of allowable limits. Think about .357 Magnum that operates in the range of 35,000 PSIG. Rarely will you see any of the usual "Pressure signs" even at this level, and .357 is nothing more nor less than .38 Spl. in a slightly longer case at an increased pressure level.

You may see pressure signs in the Magnums, .40 S&W, 10mm, .38 Super and similar high-intensity cartridges, but even then rarely. The most common "Pressure sign" you will see in any handgun is when pieces of the gun suddenly become detached from the frame of the gun, commonly referred to as a "Kaboom", or KB.

pressure signs are strictly a phenomenon related to high-pressure rifle cartridges, those normally operating in excess of 50,000, and even then usually only once even this level has been significantly exceeded!

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Gunsmithing since 1961