I'm not really sold on the 357 Sig. It was originally supposed to be a match for the 357 Magnum, except instead of a 158 grain bullet at 1300 fps or a bit more you havea 125 grain bullet at 1300 fps or a bit more. So, in a way it's really a Magnum Light.

So, look at what can be done with the 40 S&W. Use a 165 grain bullet and load using Longshot and you can have a load that clocks at 1150 fps or a bit more if you use a maximum charge. Heavier bullet, larger in diameter, with velocity that nearly matches most commercial 357 Sig SD loads and you have IMO more knockdown power.

As for those pointing out that 9mm bullets can be used to load your own, the 357 Sig has developed a reputation for being a bit "touchy" to reload due to the rather short neck length. In addition if you load a standard 9mm plated bullet to the top of the velocity chart for 357 Sig you may find your bullets coming apart mid flight. If you really want to push the 357 Sig hard you should plan on using a bullet like the Hornady XTP which can withstand much higher velocities. When you do that you'll be adding about 10 cents per round to your costs.

BTW, I've loaded 125 grain 357 Magnums to 2100 fps out of a 20 inch rifle and they stayed together just fine. However accuracy was not as good as the 140 and 158 grain XTP, probably due to a twist rate issue. Point is Hornady makes very good handgun bullets that can withstand rifle velocities without problems.

Point is I find that there are many positives to the 40 S&W that a lot of 357 Sig fans seem to ignore. First, use the correct powder and you can match the energy levels of the 357 Sig at a lower cost. For example my carry load in the 40 is a Speer Gold Dot loaded to 1150 fps and I can build an exact match to that load for practice purposes using Longshot and a 165 grain plated bullet from Extreme bullets. Means my practice loads are rather inexpensive. In addition the 40 has a straight case so I need not be concerned about the potential for Setback that can sometimes be a problem with 357 Sig handloads. Sum it all up and I am quite happy to stick with my old "40 Short & Weak".