.40 S&W "ball" ammo

[Bob Thompson]

Does anybody know or have any ideas as to why it seems that most if not all .40 S&W "ball" or full metal jacket ammo is usually truncated flat point. I don't ever remember seeing any round nose as is standard for 9mm and .45 ACP. Any ideas?

 

[stans]

The 40 S&W, like the 10mm, was designed as a modern cartridge and was designed around a truncated cone profile. I think the truncated cone allows bullets to be seated a little further out of the case while maintaining an acceptable overall length. This also allows maximum case capacity to be retained for more powder, thus giving higher velocities at lower pressures. My two cent's worth of theory!

 

[LIProgun]

Stans has it about right IMO. .40 S&W is indeed a modern cartridge designed originally for the 180 grain JHP bullet. It was also intended to fit into pistols with 9x19mm frames, which limits overall length.

I believe that when ammo makers got around to the FMJ version of the cartridge, the practical choice was to keep the OAL and profile the same as with the JHP loads to maintain feed characteristics and fit inside 9mm frames. That translated to using flat point bullets of the same general shape and loaded to the same length as the 180 grain JHP.

 

[CWL]

True.

You may feel more comfortable in knowing that the flat nose typically causes more tissue disruption on a target than a round-nose.