.357 SIG Load Data

The .357 SIG case is basically a modified .40 S&W with a skimpy bottleneck stretched approximately 0.020 inch, so that it will hold the bullet more securely. It headspaces on the mouth, not the shoulder.

Federal's goal for the .357 SIG round was to essentially duplicate .357 Magnum ballistics (125-grain JHP at 1,300 fps) in an autoloading pistol. My favorite handloads listed below achieve that level of velocity, and some even exceed it. Care must be taken when handloading bottleneck pistol cartridges such as the .357 SIG, and particular attention to lubing and sizing cases as well as chamfering case mouths must be paid.

Industry maximum average pressure (MAP) for the .357 SIG is 40,000 psi.

• Case: Speer
• Primer: Small Pistol
• Max. Length: 0.865 in.
• Trim Length: 0.860 in.
• OAL Max (Factory): 1.140 in.

Favorite .357 SIG Loads
Bullet	Powder	Charge (grs.)	Case	Primer	Muzzle Velocity (fps)	Extreme Spread (fps)	Standard Deviation (fps)
Hornady 124-gr. HP/XTP	AA No. 7	10.8	Speer	CCI 500	1344	43	10
Hornady 124-gr. HP/XTP	Power Pistol	9.1	Rem.	CCI 500	1417	34	10
Sierra 125-gr. JHC	True Blue	8.2	Zero	CCI 500	1262	60	17
Speer 125-gr. TMJ	VV N105	10.7	Zero	Fed. 100M	1418	68	16
Hornady 147-gr. HP/XTP	Power Pistol	7.4	Rem.	CCI 500	1196	27	9
WARNING: The loads shown here are safe only in the guns for which they were developed. Neither the author nor InterMedia Outdoors Inc. assumes any liability for accidents or injury resulting from the use or misuse of this data.