I will second Lee N. Fielder on this. I use S&B in 45, 9mm, 380, 32 and 25acp for pistol and have used their 38 Spl. In rifle I use their 8x57, 303 Brit and 6.5 Swede. All ammo is brass cased and reloadable. Their ammo is made to original European specs and is not the watered down stuff American ammo makers try and pawn off on you. I fyou shoot a European caliber or hunt with a older mil-surp, S&B ammo is the best bet. Clean, not corrosive, reloadable, inexpensive and made to original specs. Ya can't do better than that.
Regarding the 357 Sig - most likely made to original specs. They should have a chart available on their website that shows the ballistics of each offering. HTH. Mikey.