Al-Jim, I had a P226, and later a P229 Sport, in 357 SIG. I never got around to loading for 357 SIG, but as might be expected, any factory ammo I used was flawlessly reliable in both guns. The 357 SIG's claim to fame is of course 357 Magnum level velocity with 125 grain bullets. The SIG delivers. I chronographed several factory loads, and I don't have my notes in front of me, but do recall the 125 Gold Dot averaged 1485 FPS in the P229 Sport with a barrel just over 5" long. That exceeds any factory 9mm +P+ or 38 Super with similar weight bullets I've tested in 5" barrels. I did have a concern about bullet set back, due to the short case neck, in case I decided to start loading the cartridge. But in the end, I didn't hang on to either gun, preferring 9mm, 38 Super,etc. in ~.355" bore.......ymmv