Convert my GLOCK 40's to 357sig? Why or why not?


May 26, 2006, 08:17 PM
I have a G23 and a G27 in 40 caliber. I am trying to decide whether to buy a .357 sig conversion barrel for a couple hundred bucks. Local Glock armorer confirmed to me that the one for the G23 (a G32 barrel) will function in both the G23 and the G27. It'd be nice to basically get two more guns for the cost of one barrel.

My question is: should I even bother? Tell me why I should or shouldn't make the move to .357sig. Who thinks the .357 is better? Who thinks it's a waste?

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May 27, 2006, 12:15 AM
.357 Sig shoots much flatter than 40 S&W so if you like to plink plates or otherwise shoot longer distances, the .357 is a plus. IIRC the .357 Sig does better on barrier penetration as well. Don't know if that is important, but it is one aspect. Plus, cheap 9mm bullets for reloading are more plentifull than 40 cal bullets.

May 27, 2006, 12:27 AM
Check out Lone Wolf Distributors....they have their own brand of barrel for 89.99.

Funny thing....I just picked up a G31 in .357Sig and I am looking to buy a barrel from a G22 so I can have the best of both worlds. .40 to be a range toy and .357Sig for my HD purposes.

The ONLY thing I do not like about .357Sig is the cost/availability of the ammo.

May 27, 2006, 12:30 AM
Plus, cheap 9mm bullets for reloading are more plentifull than 40 cal bullets.

Which is offset by needing to use case lube.

Anyway though, .357 SIG is basically exactly the same, in terms of tissue crushed, as the 9mm. The increased energy may or may not give you a slight edge in the pressure wave.

Other than that, you end up with fewer shots and more recoil than 9mm, and more blast and noise than a .40, for terminal effect that's about halfway between 9 and 40.

.357 SIG may make more sense if you were getting a Mech Tech upper, but other than that, it's not all that good.

May 27, 2006, 02:00 AM
Im not a big fan of the .357sig, but it does give you more range. I do think it would make a good defense round in the 27. With the short barrel and the added velocity, I would think it would compare to a full size 9mm. I think the .40 would make a better defense round. If your going to get the extra blast and kick, you might as well shoot a bigger bullet. Thats just my opinion, though I do think the .357 is a neat round.

May 27, 2006, 02:24 AM
Which is offset by needing to use case lube.

True, but case lube is cheaper than bullets.

May 27, 2006, 06:31 PM
You don't need to use case lube for .357 Sig. You run the case through a .40 S&W carbide die to size the body, then run it through the .357 Sig die and it only sizes the mouth. But this is a two step operation instead of one.

I bought a Sig P229 with both .40 and .357 barrels. I shot 100 rounds through the 40, then switched over to the .357 barrel. The .40 barrel has never gone back on the gun, as I can reload .357 for just a little more than 9mm and it is fun to shoot.

May 28, 2006, 01:01 AM
Arn't you overworking the brass by that method Koveras.

May 29, 2006, 01:11 AM
I really like the 357 sig round...nice big bang, seems to be a very flat & accurate shooter too. The only down side I have found is the expense...if you reload, you'd probably be fine, otherwise, $$$!

May 29, 2006, 08:49 AM

I was worried about overworking when I first started using this method (got it from the SIG Forum). Several thousand rounds and multiple reloads later, I haven't seen any problems with overworking. I have noticed that after going through the carbide .40 die, the main case body isn't really worked by the all-steel .357 Sig die.

You can also get an all carbide die now from Dillon for the .357 Sig. I think the price is only $95! :eek:

May 29, 2006, 07:13 PM
Buying a 357 Sig barell is an inexpensive way to have multiple caliber functionality on a single gun. With that said 357 Sig are a lot harder on the frame and rails of the gun than most .40 and 9mm loads. Also since 357 SIG ammo is more expensive, its harder to ger proficient since you wont be practicing with that caliber as much. YMMV

Still 2 Many Choices!?
May 29, 2006, 09:48 PM
I have no experience with the round, but was told when I bought my Glock 23 that the .357 sig barrel could be bought and used for about 110 bucks...I still haven't bought one, but choices are always good... I have not bought one because it is too expensive for me to stock for another round at this time. But it is a good excuse to buy a new gun to go with the interchangeable barrel's new caliber:D ;) !

May 30, 2006, 11:15 AM
Still2many,before you decide to do a lot of shooting with that G23,check it's serial number,earlier G23 models were specifically mentioned by Glock as being NOT RECOMMENDED for 357sig,I think due to non-reinforced frames and rails.Sadly,I discovered this after I bought my G/F an older 23 with the idea that she gets 40 and I get 357 in the same gun...:( ...I guess my P239 and USPc will have to do for now...;)

matheath,a lot of people will tell you,complete with facts and numbers,that 357sig is just a glorified 9mm,and while on paper that may look to be true,shoot a 9mm,and then shoot a 357sig.I don't care how many people say they're almost the same,they are quite a bit different to shoot.I suspect those that downplay the difference haven't fired a 357sig at all,or at least not with a hotter load.Ammo costs are a factor,but if you buy in bulk from any of the bulk suppliers the cost is manageable...I would,however,recommend you shoot a 357sig gun before you buy a barrel,just so YOU know if it's a good round for you.Years ago I gave up on 9mm because I couldn't seem to hit S**T with that round,I went to 45acp.Lately,my favorite is 357sig...:D

May 30, 2006, 01:30 PM
.40 and .357 frames are identical. They don't even have the model number on them, so they really are identical. It's 9mm frames that aren't reinforced. If Glock actually made earlier .40 cal guns on the 9mm frame, you shouldn't be shooting .40 through them either!

May 30, 2006, 03:48 PM
While the frames are identical inasmuch as blueprinted dimensions,early model G23 frames had no steel reinforcements,and while they will function just fine with a 357sig barrel,they will rapidly wear out the frame on these guns.Remove the slide and look at the inner forward edge of the frame,if you see 2 small steel pieces sticking out you will be fine,if no steel insert is visible,you will ruin the frame rather rapidly using 357sig loads.There are many posts on GlockTalk regarding this problem,including photos of frames with and without reinforcement,there is a difference.I stand by my advice...

Here is a photo of a reinforced rail,mine does not have this reinforcement...

May 30, 2006, 06:08 PM
On mine, the reinforcements are covered in plastic, which is only just now starting to peel off, from being battered by the slide. Just starting to get the beginnings of slide peening from the locking block, too. If this thread had happened a couple weeks ago, I woulda said "My G23 was made in 2005, and it ain't got those!" Are you sure yours just isn't broken in yet? .357 SIG should have less recoil impulse than .40, not more. .357 with hot loads may have more recoil acceleration, but slide travel is determined by impulse. A .40 cal or .357 upper on a 9mm lower would be an extremely bad combination. But a gun that can hold up to .40 should be able to do .357 too.

It's also quite possible that the steel inserts weren't there in early Glocks, but that sounds more like something that'd call for a complete recall of that serial # range, not just the recommendation that you don't convert the guns to .357... Kinda crazy. "Don't switch to a round with less recoil, you'll crack the frame! But the higher recoil round is fine!"

May 31, 2006, 03:41 PM
okay then, what do you say to this? .357 sig barrel or get a 10mm when I can?

May 31, 2006, 04:46 PM
Get a 9mm conversion barrel and buy some Ranger Talon +P+ 127 gr ammo. Ta-da. You've now got almost exactly the same power level as a .357 SIG when you need it, and ultra cheap practice ammo when you don't. And a higher magazine capacity and lower recoil and flash to boot.

May 31, 2006, 05:18 PM
I fail to see the point of the .357 sig for self defense. I think it's just a marketing ploy to LE organizations looking for an auto with their beloved .357 ballistics. Name it a .357 and they will come. The cartridge approximates a weak factory 125 grain .357 load from a four inch service revolver. It can't handle anything heavier, of course, being of 9mm dimension. With lighter bullet weights, the .40 makes every bit as much energy. I think I'd stick with the .40 for self defense and I'd be shooting the lighter bullet weights. I don't see excessive penetration as a bonus for a civilian carry round. I ain't gonna be shootin' though car doors at fleeing perps.

Anyway, I wouldn't waste my money on a conversion. The one thing the Sig might be good for is it's a bottle neck round and might be more reliable feeding than a straight case in theory, but that's theory. I don't recall Glock having a reputation for feeding failures. :D

The .357 sig sorta reminds me of the .40 corbon, like, WHY?

May 31, 2006, 05:53 PM
This thread has peaked my intrest.

Is the 9mm conversion a drop in deal?

And Who makes Cliber conversion barrels in 9mm for the G27?

May 31, 2006, 06:11 PM
I'm really beginning to love the controversy the round stirs up. Those that have them love them, and those that dont seem to have a seething hatred towards it, whether they have shot one or not, most of which I believe is the latter, by the way.

Just curious, for those that have such a negative opinion of the round, how many have fired any handgun chambered for it enough to make a reasonable assessment of it. Is all your opinion based on internet "I heard's" and paper data, or actual experience with it?

I keep seeing the comments that the "hot" 9mm is basically the same as the 357SIG. If your going by the paper data, some do "approach" the 357SIG in velocity, but are still not there, and that comparison is based on the standard loading of the 357SIG, and not for any of the hotter stuff available. So the 9mm will always be trying to catch up. The comparisons never seem to be an "apples to apples" comparison.

Another issue I have with comparing the two is, do you use the hot 9mm all the time for practice? If so, how's your gun holding up? The guns chambered for the 357SIG were made for it, most 9mm's, especially the older guns, were not. Your Glocks will probably be fine, how about that nice High Power you like to show off? Are you willing to feed it a steady diet of +P+? ( I've personally seen what a steady diet of "hot" 9mm will do to a gun not meant for it. I've got pics if your interested.)

If you were to practice with ammo that is equivalent power wise with what you carry, the cost of ammo for the 9mm goes way up, and actually surpasses the 357SIG for practice. So the ammo savings are not there, again, if you compare apples to apples.

As much as the internet experts bad mouth the round, it really seems to be gaining popularity in the professional arenas. I'm sure all the agencys that have adopted it, just read all the good stuff on the different forums and made their decisions. They probably wouldnt have some more credible source research it, but, you never know. :)

May 31, 2006, 07:21 PM
I have a Sig 229 and a Sig 239, both have .40 and 357 SIG barrels. I just shot the 357 SIG for the first time this past Saturday. I'm not sold on it, but I'm not sure I want to sell them either. My 229 is very accurate and comfortable to shoot with the .40. The 239 is very snappy with the 357 SIG. Plenty of muzzle flash. As someone already mentioned you can shoot through doors and/or windshields, but I really have no plans to shoot through windshields or doors. Doing so would most likely land me in more hot water than I could handle.

There is a lot of hype out right now about the round, LEO switching to the round, secret service uses it, and if I'm not mistaken, federal air marshals use it. All well and good, but around me, I couldn't find quality defense ammo for the 357. I had to special order it.

Like others have said, if you can try shooting the round somewhere, I would do that. All the money you will spend on a barrel would buy a lot of .40 SW ammo. I guess its nice having 2 barrels for both guns, but in reality I can only carry one barrel at a time if I'm using the gun for CCW purposes.

June 1, 2006, 12:50 AM
I'd rather have 9mm than .357 sig...:evil:

S&W 910
June 1, 2006, 02:59 AM
I'd rather have 9mm than .357 sig...

if i had to,I'd rather get shot with the 9mm then the 357 sig

June 20, 2006, 09:48 PM
While the topic is .40-to-.357, does anyone have experience with .40-to-9mm? I have read some information that states the conversion barrel is all that is needed, while other information says that it requires a change in other parts including extractor and ejector. I like the idea of multiple caliber options without too much added cost.

October 4, 2010, 08:15 PM
I got a Storm Lake dual port bbl and can shoot faster with that handgun than with anything comparable I own (except my BHP with practice loads) accurately!

Deaf Smith
October 5, 2010, 06:39 PM
I have a G23 and a G27 in 40 caliber. I am trying to decide whether to buy a .357 sig conversion barrel for a couple hundred bucks. Local Glock armorer confirmed to me that the one for the G23 (a G32 barrel) will function in both the G23 and the G27. It'd be nice to basically get two more guns for the cost of one barrel.

My question is: should I even bother? Tell me why I should or shouldn't make the move to .357sig. Who thinks the .357 is better? Who thinks it's a waste?
I'd get the conversion barrel so if ammo prices go up and gets scarce again I'd have alternatives. I'd also get a Wolf 9mm barrel for your glock to!

But for me... hahaha, I have Glocks in 26,19,17,32,27,23 flavors so I have all three already.


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