.357 Sig Shield conversion. Advice needed!

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Epeeist

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So I have become enamored of the .357 sig cartridge, and I would like to convert my Shield (9mm, recent make) to fire my favorite defensive cartridge. My question is basically will the .357 Sig barrel fit inside the 9mm slide (I would of course beef up the spring and get a metal guiderod)?

I know I could by a .40 and get a replacement barrel, but then I have a shield I probably won't shoot and a random barrel that I won't use.

Thoughts and advice appreciated!
 
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My first thought is, what .357 SIG barrel? Since there is no 357 SIG Shield, there is no 357 barrel to put in either a 9mm or .40. Unless you know something that I am unaware of.
If you really want a sub compact.357, my advice is sell your Shield, and get a Glock G33. Then, if you wanted, you could get a 9mm conversion, or drop a factory .40 barrel in, and shoot 3 calibers out of the same pistol.
 
Even if a .357 Sig barrel was available, the breech face of your 9mm Shield is too narrow to accept the .357/.40 case. Mechanically it is not a viable conversion.

I am also a fan of the .357 Sig. The route suggested by Mustangman is a good option. For a slightly larger pistol, purchase a .40 caliber M&P compact. .357 Sig barrels that fit the compact are available from a number of vendors.
 
There's a .40 to .357sig conversion barrel on ebay, saw one a few weeks ago. Made by Remsport, whoever that is.

I've not done a .40 to .357 conversion on any pistol but shoot it thru a G32 and would love to convert my 9mm shield to .357. But EVERY conversion barrel I've seen is for .40 not 9mm.

I think the barrel forks on the .40 are wider than the 9 so I'd say it won't work. I've searched and found no 9s converted.

You'd need .40 mags as well.

Extractor would probably have to be modified or replaced as well for the larger case size but I'd assume a .40 extractor would drop right in.
 
9 goes into 40 but not vice versa without modification.

I had a Gen2 Glock23 that I wanted to convert to .357sig. I had to upgrade the frame to Gen 3 in order to accommodate the additional pressures.
 
Thanks for the advice folks! I guess I just need to trade my current one in for a .40 and swap out the barrel. I have a trigger job, talon grips and fiber optic sights on my current one, so I was hoping to find one with most of that already done. Maybe I can find a good deal on a Pro model.

FYI I do have .357 sig in my .229 Equinox for compact carry. I just like a single stack for summer carry ease.
 
I too became enamored with the .357sig cartridge, so I went out and bought a P239 in it. Then I ordered a .357 barrel for my P224 Equinox .40S&W. Now I'm looking for a .40 barrel for the P239 so I can practice more cheaply. Pretty soon I'm going to get some dies to reload all the .357 brass I've shot up...it's never endingLOL. Biggest problem with the .357 sig is cost of range ammo; but it's a great little cartridge. Even the range ammo zips along at 1550 to 1600. Muzzle blast and report are impressive. People at the outdoor range I frequent are always wanting to know what I'm shooting out of "that little gun". If you haven't looked at a P239, consider it because it is a comfortable gun to shoot; fits my hand perfectly.
 
tlawler said:
I too became enamored with the .357sig cartridge, so I went out and bought a P239 in it. Then I ordered a .357 barrel for my P224 Equinox .40S&W. Now I'm looking for a .40 barrel for the P239 so I can practice more cheaply. Pretty soon I'm going to get some dies to reload all the .357 brass I've shot up...it's never endingLOL. Biggest problem with the .357 sig is cost of range ammo; but it's a great little cartridge. Even the range ammo zips along at 1550 to 1600. Muzzle blast and report are impressive. People at the outdoor range I frequent are always wanting to know what I'm shooting out of "that little gun". If you haven't looked at a P239, consider it because it is a comfortable gun to shoot; fits my hand perfectly.
Click to expand...
My outdoor range is my back yard (102 acres of soy beans). But, people have asked what I was shooting? It's my MP .40 2.0 or 1.0, with a SIG .357 barrel in them. That is one LOUD round!
When I go to an indoor range (nearest one is 52 miles away) and shoot the same guns, some people ask there as well. They can't believe how LOUD the .357 SIG round is. Either gun is now my EDC gun.
 
Epeeist said:
Thanks for the advice folks! I guess I just need to trade my current one in for a .40 and swap out the barrel. I have a trigger job, talon grips and fiber optic sights on my current one, so I was hoping to find one with most of that already done. Maybe I can find a good deal on a Pro model.

FYI I do have .357 sig in my .229 Equinox for compact carry. I just like a single stack for summer carry ease.
Click to expand...

My I ask what brand barrel you are going to use in this conversion?
I got rid of my .40 a while back, and now have a .45, but might be able to pick up a used one very cheap now, and might look into this.
 
mustangman said:
May I ask what brand barrel you are going to use in this conversion?
I got rid of my .40 a while back, and now have a .45, but might be able to pick up a used one very cheap now, and might look into this.
Click to expand...


Can I make a recommendation? There is an auction sight that sells and auctions factory S&W barrels. They also do the same for Storm Lake barrels.
I bought my SIG .357 barrels from there, and won an auction on a Storm Lake .40 to 9mm conversion barrel. I was originally supposed to buy my SIG barrels from Midway, but they shipped them to 2 different people! I can understand one time and forgive you, but twice? I canceled my order, was reimbursed, and used the auction site.
OP, good luck and keep us posted as to what you decide to do. ;)
 
Disabled1 said:
Can I make a recommendation? There is an auction sight that sells and auctions factory S&W barrels. They also do the same for Storm Lake barrels.
I bought my SIG .357 barrels from there, and won an auction on a Storm Lake .40 to 9mm conversion barrel. I was originally supposed to buy my SIG barrels from Midway, but they shipped them to 2 different people! I can understand one time and forgive you, but twice? I canceled my order, was reimbursed, and used the auction site.
OP, good luck and keep us posted as to what you decide to do. ;)
Click to expand...

Thanks for the recommendation, but I don't think it applies to this situation.
The OP is talking specifically about a Shield, and I was also referring to Shields in my post as well.
Since there is no .357 Shield, I'm assuming there is an aftermarket company or companies that make a barrel for this type of conversion.
I in fact saw the Remsport Shield 40 to 357 conversion alluded to in a previous post, and was wondering if that's what he was going to use or was there something else out there.
I definitely hope the OP keeps us updated on this.
 
I'm wondering if sights would be different for the 357sig Shield conversion? They were different on my Sig P239 which I sold as it always felt bulky and nose heavy. I did order a Remsport 357 sig barrel for my 40 Shield so I guess I will know in a few days
 
.40 S&W is to .357 SIG as 9x19 is to...?
1) .30 LUGER
2) .22 TCM
 
Clete Torres said:
3) Neither. 9x19 is closer to .380, but still not safe to fire in a .380 pistol.
Click to expand...



I was really referring to the bottleneck aspect. Without getting too technically picky, I was thinking the answer would be 1 and 2. Perhaps I should have said 9mm LUGER and been more specific.

Interesting that the .357 sig is more powerful than the .40 S&W whereas the .30 Luger is less than the 9mm.

Again, not getting too technical - not trying to start an argument. I was just making a correlation between the straight wall cartridges and their respective necked down versions.
 
I am almost certain that you would have to start with the .40 variant and then get an aftermarket barrel (probably costly, but if you paid a good reputable manufacturer enough they would/could do it). Whether the juice is worth the squeeze is unlikely* - the round is overhyped if one looks at the objective data. I say that owning one (a G33) and carrying it almost daily.

Yes, LE agencies that have issued it do well in shootings, but that is almost certainly a function of the fact that the agencies that choose it were influenced by serious shooters, and thus trained a lot and well.

*Your money, your choice. I've made more than a few choices in firearm modifications that from any objective analysis are borderline stupid myself.
 
Remsport currently lists the 40-357sig barrel as out of stock. 139.00 shipped. If you can get a .40 shield for around 225, it might be worth it.
 
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