M&P 357sig/40 vs 45

[torrejon224]

I own both and the 357 sig is hands down my favorite however unless you reload make sure that you can find and afford the ammo! Here in Oregon 357sig is almost impossible to find but I lucked out and bought two cases of Speer Lawman 125tmj off Gunbroker for $17 a box. It usually goes for over $30 a box. I do reload but needed the cases and also prefer to break in new guns with factory ammo.

 

[kmyers]

.357 SIG is my favorite caliber in both M&P and in the XD. It is a LOUD!! caliber.

 

[Sneaky]

I began to consider CCW after 3 guys tried to carjack me and my wife. I got away unharmed, but considered myself lucky. So, in that situation, I think having a 15 round 40 or 357 sig far outweighs any advantage a 45 would offer since they typically only chamber half as many rounds.

Also, the 357 Sig and 357 Magnum are supersonic (that is why they are louder than other rounds). So, right behind the projectile comes a shockwave that provides an added measure of knockdown force. All other pistol rounds are subsonic.

 

[Sneaky]

I am a 357 fan also. As noted in another post, both 357's are supersonic and that is why they are so much louder than other pistol rounds. Milliseconds after the bullet hits a target the shockwave arrives. Since body fluids cannot compress, the shockwave produces tissue and organ damage making a hit from either of these two rounds one shot stoppers. A quick Google search on the topic will reveal numerous articles regarding this info.

 

[M29since14]

All other pistol rounds are subsonic.

Interesting observation there. Last I checked the speed of sound in air was somewhere around 1120 FPS, depending on your density altitude. There are quite a few pistol rounds that exceed that, notably all of the magnum revolver rounds, the 9x19, the .38 Super, etc., etc. Being super-sonic doesn't seem to add much to the stopping power of, for example, 9mm ball, and not being super-sonic doesn't seem to bother the .45 too much. The improved indications of stopping power of the various small-caliber pistol rounds seem more to be due entirely to recent advances in bullet design.

The SIG is a nifty little round (if someone else is paying for the ammo) but it really doesn't seem to do anything a .38 Super/9x23 (competition gun) or 9x19 (duty gun) won't do just as well or better, if all things are considered. Cost to shoot is the main gripe. Naturally, one thing government agencies never seem to consider much is cost. The ducks are always flying! (for them )

 

[Silvergoose]

Hust a note: AMMOGUIDE.COM has a great site for comparing ballistics, load data and can give a visual comparasion of the different rounds.

I have found the information helpful, eventhough I do not reload as of yet.

Good Luck

 

[Rastoff]

Well, you guys dragged up an old one. It's notable because I don't think the .357 is available from S&W anymore. You'd have to buy a .40 and then get a .357 barrel from an aftermarket company.

Oh yeah, the shockwave from something as small as a bullet doesn't do any significant damage.

 

[BrianE]

Definitely an oldy as I ended up with the 45

 

[Lost Lake]

I began to consider CCW after 3 guys tried to carjack me and my wife. I got away unharmed, but considered myself lucky. So, in that situation, I think having a 15 round 40 or 357 sig far outweighs any advantage a 45 would offer since they typically only chamber half as many rounds.

Also, the 357 Sig and 357 Magnum are supersonic (that is why they are louder than other rounds). So, right behind the projectile comes a shockwave that provides an added measure of knockdown force. All other pistol rounds are subsonic.

You kind of snuck in a 3 years + old thread and replied like it was yesterday.... That's Sneaky!!!

If you think sonic shockwave is adding knockdown power, you better Google that a couple more times.

It ain't happenin'

Welcome aboard!

.

 

[erle]

I just became a member & for what it's worth--I'm a 357 sig fan. I have a Glock 23 with 9mm, 40, & 357sig barrels. I have shot my Son's 357sig M&P & have a new one coming for myself.
Reloading the 357sig is no problem for me, but I do take special precaution with the headspace. Instead of grinding the sizing die, I ground a few thousandths off the shell holder! Works great.

 

[Enzo]

The round count for me doesnt matter because in MA you cant have anything more then 10 unfortunately .

If you get the 357sig can you put the 40 barrel in like you can vice versa? Im a huge 357 fan and I really want one...

Tell me some more about the 357sig! I want to get all the knowledge of this caliber possible.......

Thanks to all so far and to the ones in the future!

Like you, I'm in Massachusetts too so I just bought a 45c. Eight +1 or you can use the 10 round mag with an xgrip. Smaller than the full size 45 and smaller than the full size 9/40/357 M&P.
The 357 is a great round, flies flat and fast, but hard to find, very expensive and very loud.

 

[gkitch]

I bought a full size M&P in 357Sig a few years ago and immediately obtained a 40 S&W Bbl for it. I have shot it plenty with both rounds and all are 100% reliable and accurate! I am fully happy with this pistol.

Like you, I prefer the 357 Sig for carry. Still, it is useful to have the option of calibers as sometimes we carry/shoot what we have. The magazines are the same for both and so are the recoil springs, so it is just a matter of swapping out the tubes and making sure that the ammo in the mag is THE SAME as the markings on the barrel.

 

[erle]

The 357 Sig cartridge was developed by Sig in order to have a caliber that would (1) Be lighter in recoil than the 10mm, (2) Have somewhat comparable ballistics to the 357 Magnum revolver load, (3) Operate in an auto.
It is different from most auto ammo in that it is a bottle neck case (like most high powered rifle ammo). Consequently, special care must be used in reloading.
It is not really a .40 cal case that is necked down to take a 9mm bullet, but almost. The 357 sig case neck is just a little longer. There was some confusion when it first came out about it being head spaced on the rim or the shoulder. I have an earlier reloading manual that states it head spaces on the rim. However, I have since learned that it actually head spaces on the shoulder, & I do all my reloading by measuring from base to shoulder.
Ammo is quite expensive unless you reload.
The 357 Sig seems to be popular with Law Enforcement but has been slow catching on with the general shooting public.

 

[vegasgunhand]

I currently own an M&P 40FS with the .357 Sig barrel. I bought the extra barrel because I was gifted about 5,000 rounds of Speer Gold Dot .357 Sig.

I am a retired federal agent, and current firearms instructor. The U.S. Secret Service and the Air marshals are probably the biggest users of .357 Sig ammunition. It is a great law enforcement round for sure.

That being said, when you look at actual law enforcement shooting results, there is a very slim difference between the major LE calibers in use today. Approximately 4 to 6 percent difference in one shot stops.

Basically it's ALL bullet placement! If you don't get a hit in a vital area, you might not get the subject to stop the attack. No caliber will make up for a poorly placed shot.

 

[Duster340]

I have yet to shoot a M&P .45, but I do have a .40 FS and have conversion barrels for .357 and 9mm both. One firearm that cans shoot three calibers. Nothing there to not like.

Very nice combination and I have had no problems with mine.

x2 I have a 9mm for my 40 FS. Shoot lots of rounds through both and love it. Haven't got a 357sig barrel yet, not sure I would gain much as the 40 & 9 seem to fit the my current needs.

 

[Tex1001]

357 SIG/40S&W vs 45ACP

I have a FS M&P 357SIG that I matched with a 40S&W barrel. I have a M&P9c that I have matched with a 40S&W barrel. I also have a FS M&P45. I have carried a 45acp professionally and CHL (Colt 1911 or Officer's ACP) for 30 years. I think that the 45 is an outstanding bullet diameter. The 40 is not far behind. The 357- SIG or magnum is a great shocker with 124/125gr bullets. I carried a magnum before I switched to the 45acp. I would feel well armed with any of the three, so I won't try to sway you on any one of them.
Barrel conversions are straightforward between the M&P 40/357 full size pistols. Simply swap out the barrels and use the same magazines.
Going from 9mm to 40 requires some barrel fitting (At least on my M&Pc). I had to shave the chamber sides at the rear of the chamber to facilitate barrel/slide fit. I also had to slightly tweak the extractor and polish a sharp corner on the breach face to get reliable feeding. Also need the dedicated 9mm mags.
-If you go with the 357SIG, get ready to reload. Here's some tips: Starline has great brass and no shipping charges. Do NOT try to use Berry's or Ranier plated bullets. Ramshot Silhouette powder will give max velocities with no pressure signs. Plus, Silhouette powder will help reduce your muzzle blast and almost eliminate muzzle flash.

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