As others have stated, 40 S&W blends the horsepower of 45 ACP with the capacity of 9mm. It's an excellent compromise round between the two calibers…./
/….9mm has come a long way, and there's many very good options for ammo available, however the terminal ballistics data shows that 40 S&W is still superior to 9mm.
Two comments:
1) Some folks will say "blend". Others will say the .40 S&W just falls short of the power of the .45 ACP and sacrifices the magazine capacity of the 9mm Luger.
Like most compromises it doesn't to anything particularly well.
Now… to be fair, the .40 S&W pretty well replicates the black powder era 38-40 ballistics and that has gotten the job done since 1874.
2) 9mm Luger hollow point performance has come a long was since the need for the .40 S&W was first envisioned. That improvement has eroded much of the actual real world advantage of the .40 S&W over the current 9mm hollow point offerings.
What hasn't changed are the realities that:
- all handgun rounds are inadequate;
- bullet placement still matters more than slightly larger bullet diameter; and
- more wound tracks represent more potential for an incapacitating hit than fewer wound tracks; and
- most shooters, even experienced shooters can score more A zone hits in the same time frame with 9mm Luger than they can with .40 S&W.
Then there's the oddity of .40 S&W recoil. It's heavier than 9mm Luger, but "snappier" than .45 ACP. For many shooters the slow "push" of a .45 ACP is more manageable than the "snap" of a .40 S&W, especially in a compact sized pistol.
Consequently, if folks want capacity 9mm is the go to round. If they favor terminal ballistics then .45 ACP is a more likely choice, especially in a compact pistol.
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I don't think the .40 S&W is going anywhere as there are plenty of them out there. But I also think it has had it's day in the sun and is on the back side of the growth curve.
Could it make a comeback? Sure it could. The .38-40 and .44-40 sure did.
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