The 357SIG conversion barrels available for most 40SW pistols is what initially kept the 357SIG growing in popularity and ammunition choices. Although used as assigned caliber by a few agencies, civilian use was low due to limited ammunition bullet style and weights / high ammo prices and sparce distribution (sort of all fits together). Ease and low 'startup' costs for 40SW owners to grab a conversion barrel and go shoot exposed more people to the advantages of the 357SIG. Ammo selection now has readily available commercial choices from 90 to 158gr plus some low volume specialty rounds out past both ends of the mainstream ammo scale. More brands are being loaded and prices as compared to other calibers have actually come down. But the ease of conversion between 40SW and 357SIG for the consumer means less incentive to carry a separate commercial pistol model in the production line or inventory.
Look at this overview CALIBERS -- 357SIG Advocacy for a nice "bullet" point summary of the favorable aspects of 357SIG as a caliber. A good factor for a CC size weapon is that it was designed around a 4" barrel length - not much zip lost at 3.8. For reloaders, check this alternate view of headspacing the 357SIG: www.realguns.com/archives/001.htm
RE the 'new' SA offering: if it is in the XDm series, it will not be a single stack. Anything of that design would be a entirely new pistol series. SA distribution has not yet completely filled the present XDm series of models (4.5, 3.8 ) in all calibers (9mm, 40SW, 45acp) with all grip sizes (full, compact). IMO Just look to what is needed for release to finish the XDm series in 45acp. Legally, import of a 380 will not happen due to the points system.
If 357sig loaded ammo prices would drop, it could be possibility. I like my 357sig a lot. I'm thinking if Wal-mart would sell 357sig ammo then it would catch on. The 45gap is kinda like 38/357 to close in performance for those that are entrenched.
Would like to see a single stack 45 for carry. A XDc-45 ultra-carry, perhaps.
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