why convert from a .40S&W to a .357 sig?

[FongP]

i was reading about people doing this and might even consider it....
BUT, why? what are the benefits of the .357 sig over a .40? and could it possibly hurt the gun in the long run?

[kurac]

You will pay more for ammo, have less selection and be able to shoot a lighter bullet faster.

[bonjing]

i don't think there is any more damage that can happen to your pistol from shooting 357sig, as long as the firearm is capable of taking it. ie I have a 2nd gen glock 22 that i would like to convert over to 357 sig but from what I understand the frame cannot take it, i may be wrong though. but as for any benefit, i just enjoy shooting the snappier round, but the down side is that the ammo does cost an arm and a leg.

[cadurand]

The ammo price argument is quickly disappearing. We're talking a difference of $20 per 1000 these days.

40S&W is probably easier to find though.

I like .357SIG because it shoots nice and flat. 40S&W shoots pretty flat too though. .357SIG is louder out of the same pistol.

[USMCbrat]

So I have a Glock 32 and am considering the .40 S&W barrell just to see if the gun is less jumpy. Not sure if I will do it yet but if I do, it is nice to have to different cal options.

[tatsuosan1964]

Because you can have a second caliber for an existing pistol for a fraction of the cost of another pistol. I purchased a like new barrel in .357 Sig for my G22for only $80 shipped. Yes, ammo costs more but I can practice with .40 S&W because the only part that is different between the G22 and the G31 is the barrel. Same mags, same everything.

Is it practical? Probably not as the ballistics in modern ammo make 9mm, .357 Sig, .40 S&W, and .45ACP all effective self defense rounds. If we were to use that line of logic though then we would all be shooting 9mm because it is usually the cheapest to shoot. It's nice to have choices and I have something that shoots every one of the mentioned calibers. Not very practical but I know that in a group like CalGuns, I'm not alone.

If you are shooting a modern firearm, and a comparable .357 Sig model is also offered by the same manufacturer, then you can safely shoot the .357 Sig with a simple barrel swap. They are probably basically the same pistol, just different barrel. So save some money and just buy a barrel. It is a fun round to shoot. As cadurand and bonjing already stated, .357 Sig is a snappy, flat shooting round. As far as snappy, I really don't notice much of a difference between the .40 or the .357 Sig. Flat shooting because the standard .357 Sig round is traveling several hundred feet per second faster than the .40, using a smaller bullet. You can also get light bullets in .40 that have similar velocities to the .357 Sig round if you want to have just the one caliber.

[Miltiades]

Use light .40 S&W ammo from Corbon

Corbon sells a .40 S&W product that uses a 135 grain hollowpoint bullet.

Corbon 135 grain .40 S&W hollowpoint ammo

The ballistics of this round are:

Muzzle Velocity = 1325 feet per second
Muzzle Energy = 526 foot-pounds

This is almost identical to the performance of most .357 Sig ammunition, which usually has a 125 grain bullet weight and muzzle velocity of 1300 fps plus. So rather than buying a .357 Sig barrel for your .40 caliber gun, you can get the same "light and fast" performance by buying the right .40 caliber ammo.

[Fjold]

What's the advantage of flatter trajectory in a pistol used for defense? I could see it in a single shot hunting pistol but at the ranges that the sights of a autoloader will let you shoot accurately, how much trajectory difference is there?

[LAK Supply]

With manufacturers like Double Tap Ammo around there's no real reason to convert to .357 Sig.... some people just like to have the boom.

The .40 can use much heavier bullets and shoots the light stuff almost as well.... 135 gr at 1425 in the .40 vs 125 gr at 1525 in the .357 Sig. The Sig can't shoot anything over 147 gr while the .40 goes on up to 200 gr.

In the less-common autoloading cartridges I prefer 10mm hands-down..... 135 gr on up to 230 gr. I can launch 200 gr hardcasts out of my factory barrel at 1300 and 135 gr at 1600. Add the 6" Jarvis and the velocity goes up 100-125 fps. 230 gr hardcasts at @ 1250.

If you're into the less-common stuff get the 10 for sure.

[Greg-Dawg]

Because it saves you money on buying a new gun with different caliber..

My G35.

[RideIcon]

id love a p99 40 converted to 357 sig!!!

[Bobula]

I've got a .357sig barrel for a G27 for sale. Just a bit to snappy for me.

[FongP]

id love a p99 40 converted to 357 sig!!!

thats what i have! and why I'm wondering... but it seems like I should just buy different ammo. No point in wasting a couple bills on a new barrel.

[Glock22Fan]

why convert from a .40S&W to a .357 sig?

Why indeed?

[Parag]

BUT, why?

Why not?

-- Parag