Why not .357 Super Sig

[Tinbucket]

The .357 Sig is a necked down .40 S&W case with a .357 bullet.
Makes about much sens as reducing the 10mm to .40 S&W.
Does anyone make a barrel for a 10MM Colt or other with the chamber cut for a 10MM case necked down to.355 or .357.
Doesn't seem that it would take too much more recoil spring and perhaps less due to lighter bullet.
You could get a 125 grain bullet up to 1700fps perhaps.
A .110 grain bullet up to 2000 fps perhaps.
If I were going to engineer this I sure wouldn't design for mediocrity.

[Cheapshooter]

9X25 Dillon
https://en.m.wikipedia.org/wiki/9×25mm_Dillon

[Hal]

Given the choice between the .40 S&W brass and the 10mm auto brass, as a basis for a "hot rod", I believe I'd go with the .40 S&W.
It's stronger.

The 10 mm uses a large pistol primer & as a result, SAAMI rates the maximum pressure under the small pistol primed .40 S&W.

A fellow TFL poster, Clark - the guy that shoots guns to destruction - pointed that fact out a number of years ago.

IIRC, he also "blew up" one of each with overloads to prove his observations.
I could be wrong there though.
Perhaps he'll see this thread and clarify it.

[74A95]

The .357 Sig is a necked down .40 S&W case with a .357 bullet.

The 357 Sig uses a .355 bullet, not a .357 bullet. I know, it makes no sense.

https://en.wikipedia.org/wiki/.357_SIG

[44 AMP]

The 357 Sig uses a .355 bullet, not a .357 bullet. I know, it makes no sense.

74A95, What part doesn't make sense??

The very first sentence in the history section of the link YOU provided, explains why it was named .357 Sig.

As to why they chose to use a .355" bullet instead of a .358"? Practicality is probably the reason. Very FEW .358" bullets are optimal for use in semi autos. The vast majority of .355" (9mm) bullets, are.

If you are making a new round in .35 caliber, for use in semi auto pistols, choosing a bore size that would exclude the use of the HUGE range of 9mm bullets would be a poor market decision.

[Tinbucket]

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