357 Sig

littleriver1 · #1 02-07-2013, 08:43 AM

What is the difference between 357 Sig and 357 magnum?

Simmy952 · #2 02-07-2013, 08:56 AM

The .357Sig is a necked down .40 with a 9mm sized bullet. It has more muzzle blast and flash than a .40 with about the same muzzle flip. Has more energy coming out of the barrel than the 40 and supposedly penetrates better in car doors and windshields. It is easier to shoot and handle than the .357 magnum. The .357 Sig is a fun round to shoot but can be a bit pricey.

No. Bullet Type Weight FT. LBS. MUZZLE25 Yds. 50 Yds. 75 Yds. 100 Yds.

357 Magnum 357B JHP 125 gr 399 1194 1117 1057 1008 967
357 Sig 357SA FMJ/FP 124gr 512 1350 1242 1158 1093 1040 0.45

You get about the same ballistics with an updated platform. You can find a wide variety of semi auto handguns from various manufacturers in the .357 Sig. There were not many .357 magnum autoloaders built.

FlyFish · #3 02-07-2013, 08:58 AM

They're two entirely different cartridges. 357 SIG is a semi-auto rimless cartridge that's basically a necked-down .40 S&W (it's not actually made that way), designed to duplicate .357 Magnum ballistics with 125 gr. bullets out of a short barrel. .357 Magnum is a rimmed revolver cartridge that can be thought of as a lengthened .38 Special loaded to higher pressures. Wikipedia has a good discussion on the development of both cartridges, along with just about any other caliber you can think of.

JPriest · #4 02-07-2013, 09:02 AM

357 Sig is made for autoloading pistols and is essentially a .40cal casing necked down to 9mm. They were going for the same kind of speed and power as a 357 magnum. They certainly aren't interchangeable in the same gun, though many .40 cal pistols can be made to fire the 357sig by simply swapping out the barrel.

According to a table I have from Hornady the 357 magnum 125gr has a muzzle velocity of 1500fps and energy of 624ft/lb. This compares to a 124gr 357 Sig at 1350fps and 502ft/lb.

For heavier loads around 158gr, the magnum is 1250fps and 550ft/lbs and the sig is 1225fps and 490ft/lbs (147gr).

littleriver1 · #5 02-07-2013, 09:55 AM

OK, got it. thanks for taking the fogg out of it.