Yep, enjoy what you like when it comes to pistols & calibers. You only have to suit yourself.
Why would it matter if it's not more "popular" among service (LE/Gov) users, though? What would make it more popular, anyway?
What's "shooting flatter" at typical defensive handgun distances? Does it matter at 5-10 yds?
The .357SIG is more or less a slightly faster .355/9mm using a middle range (for caliber) bullet weight (125gr), as the heavier 147gr offering never really seemed to become popular.
Once you look beyond the original marketing hype of it being the modern pistol equivalent of the "vaunted" 125gr .357 Magnum that produced 1450fps from some 4" service length revolvers ... it's a .355" caliber 9mm bullet being pushed to around 1350fps most service length barrels. (Back in the days when I was carrying a .357 4" service revolver, it wasn't uncommon to find chrono testing which revealed that some of the popular 2 1/2" snub revolvers of the day - M19/66 & Pythons - could be found to produce velocities running 1250-1300fps when checked with some of the 125gr Magnum loads of the day, and 1400-1450fps out of 4" barrels.)
Anyway, the major ammo makers who do a lot of LE/Gov business offer a range of .357SIG loads which are mostly running only 100-150fps faster than some of the 124gr +P & 127gr +P+ 9mm loads being produced for LE sales, and about the same velocity as some long established 115gr +P+ LE loadings.
Federal Tactical Bonded 1350fps
http://le.atk.com/ammunition/federal...ls.aspx?id=534
Federal Tactical HST 1360fps
http://le.atk.com/ammunition/federal...n/default.aspx
Speer LE Duty Gold Dot has 2 offerings, 1350fps & 1375fps
http://le.atk.com/ammunition/speer/handgun/default.aspx
Winchester has Bonded & T-Series, both producing 1350fps
http://winchesterle.com/Products/han...s/default.aspx
http://winchesterle.com/Products/han...s/default.aspx
Remington has a couple of LE offerings, both doing 1350fps
http://remingtonle.com/ammo/pr_ballistics/357_sig.htm
Yes, some of the small custom ammo companies are advertising faster loads. So what?
Having attended my fair share of armorer classes for a few of the big name gun companies who do LE/Gov sales, one of the common things said about the .357SIG cartridge is that it's considered to be a bit harder on guns than even the .40 S&W cartridge. This is one of those things that may be a factor when considering support & maintenance during the projected service life of a duty weapon. (Of course, the 9mm +P & +P+ loads could accelerate wear & tear on service weapons, too, of course.)
Ammo cost & availability can be factor, too.
"Carrying more energy". Paper ballistics and ME figures are all well and good for those folks who like to peruse them, and ammo companies will certainly make them available in their commercial & LE catalogs
... but how any particular caliber/bullet actually behaves under anticipated circumstances is of more interest to major users of service weapons. Nowadays the engineering behind bullet design and how bullets are made to behave within stated "performance parameters", which can be checked via carefully controlled scientific testing, is often of more interest to LE/Gov users.
Not everybody in LE may necessarily agree with how they want to interpret ballistic performance, either, so the ammo companies still make variety of LE loads so any & all LE/Gov users can find something which appeals to whatever criteria it is they use for making ammunition selection.
If the .357SIG was ever going to dominate LE/Gov sales, it would've done so long before now.
If someone likes it, especially as a private citizen/gun owner, there's enough ammo offerings to be found, as well as a selection of pistols chambered to use it.
Don't be surprised if sales don't meet those of the other common service/defensive calibers, but ask yourself why it would matter for an individual choice.
Several years ago I asked a Glock LE rep, just out of curiosity, how many .357 guns were being sold to LE. He told me the company didn't make those figures available to the reps, but that he'd done some asking around (out of his own curiosity) and had been told that apparently they were making 1 gun chambered in .357 for every 2500 guns chambered in other calibers, and that included LE sales. (He didn't seem to know if that meant out of 2500 in each caliber, or combined out of all calibers.)
S&W originally offered their new M&P pistol chambered in .357SIG. Aside from a rather limited production run of MSW357V (Sigma) pistols done many years ago, the M&P 357 was their first attempt to offer a mainstream LE pistol chambered in that caliber. They sold some to LE and private/commercial buyers, but the sales were such that they've apparently dropped that caliber from standard production (reserving it for any LE orders). Too much demand for the regular calibers.
If you like it, there's nothing wrong with that. Enjoy. The gun & ammo companies will thank you.
It's already done something the 10mm couldn't do, which is remain a service caliber.
