[Critch]

I bought a barrel to run 357 Sig in my G23. I was using a 40 S&W magazine and everything went fairly well for the first two mags, then every 5 rounds or so the 357 Sig rounds would be tipped down...frustrating.
Saturday I was in my favorite gun store and he had a used Glock 357 Sig magazine, which he sold to me for $5. Not bad. So I went back to the range and shot two magazines and not a single problem...

There must be some subtle differences in the magazines that I don't see....

On another note, not Glock related, I had a brand new Rossi 92 357 magnum lever rifle out there shooting it and it broke after about 40 rounds, the ejector fell out. Brand new rifle. I took it into the dealer this morning and he is sending it off for repair. Oh well...

 

[Mike-M]

Look at the top of the magazine followers, both 40SW and 357SIG. What is the revision number on each? It's that sort of information that should be provided with ALL questions of this type. The current 357SIG is 4, and 40SW is 10.

Also, is the 357SIG barrel Glock OEM, or aftermarket? That's also essential information that should have been in your first post.

 

[1canvas]

One thing I always noticed about Glock 357Sig mags is when you unload a mag by thumbing the rounds out they want to nose dive into the mag no matter what mag.
That said, I have run hundreds of Sig rounds (GD, HST, and Georgia Arms) through my Gen3 23 with both .40 mags and 357 mags with no problems, that’s using the Glock OEM G32 barrel.
I have a Gen4 23 with a new OEM G32 barrel but only put a few rounds through it but haven’t had an issue with it.
Many tout the 357Sig feed reliability because of its small bullet going into a big hole which creates a funnel effect, yet I often see people posting about the Sig bullet nose diving and stopping on the feed ramp.
I would not do that conversion with an aftermarket barrel.

 

[sig357fan]

I've carried and shot 357 Sig for several years, shooting several hundred of factory ammo and several thousand reloads in a couple of different Glocks, the only time I have ever had a 357 Sig round fail to feed was in an aftermarket barrel in a Glock 35, that set up only saw my reloads and I was able to tweak my reloads to work.

the problem I had with my reloads was that I was loading max loads and loaded them as long as I could to fit the mag, which were too long to feed into the aftermarket barrel, once the COL of my reloads were brought closer to recommended COL they functioned fine.

so if you don't reload, try a different brand of ammo, measure COL of the rounds before firing and see if that has an effect.

 

[powernoodle]

The difference in the two mags, if any, could be attributable to the need to address the faster-cycling slide on the 357. Many moons ago when I was full of testosterone and played with converting Glocks to 357, that was an issue for me especially with the 27/33 and its short slide.

 

[fastbolt]

At least a couple of gun makers I can think of provide magazines with their .40/.357 models that list both calibers on the same mags. Glock isn't one of them.

I've been told by Glock folks on more than a couple occasions that they make different mags/followers for .40 & .357 for good reason. If they could use the same mag for both calibers in their guns, they would.

Back in the early 2000's, when I was idly thinking about picking up a (then) cheap factory G33 barrel for my newly acquired G27, the LE rep made a point of telling me to be sure to get some G33 magazines to sue with that barrel (after he checked my G27's serial number to confirm I could use the G33 barrel in that specific G27 frame back in those days).

 

[LostinTexas]

I always thought the followers were a shade different. Maybe not, many who have made the switch say range time is fine with 40
Life depending on it, use 357 mags or follower.
Just repeating what I've heard.
I have toyed with getting a 357 Sig barrel but just can't justify it. If I got one for a little of nothing I probably would, I guess.

 

[Critch]

It's a Rock Slide aftermarket barrel. The 357 magazine follower has a 357 on it, and the number 3 toward the front. The .40 caliber mags all have 40 and then the number 9 on the follower. I really didn't have any problems with it until the other day..ammunition was some I bought from Freedom Arms and some Winchester I bought at Academy..

Well, tomorrow's another day...hopefully at the range..

If it continues to malfunction I may sell the barrel and invest in a Glock 32.

 

[quantico]

I have run many thousands of rounds thru my glock 31 and 22 and sig 239 and 229 in 357 sig. I have used mostly dedicated 357 sig mags, but used some glock 22 and 23 mags back when the Clinton's kept us safe from owning many guns and the correct magazines. I had good luck with the g22 mags but had little choice because as of 1994 there were few glock 31 mags in the world.

The 357 sig and 10mm are my most frequent rounds , although I have a lot of 45 ACP guns that I love to shoot as well. 9mm might expand, but a 10mm and 45 ACP will never shrink.

I see quite a difference between the 40 and 357 sig mags. I assume your at least running all glock factory mags.

 

[quantico]

For 100 dollars used you can usually buy a used glock factory barrel. I have had no issues with glock mags and glock barrels, so you might want to do that.... or just buy a g 32. Either way

 

[Wizzz]

Nothing but jams even with stock 357sig glock barrels for me. I gave up on the caliber altogether for glock and sig sauer in 357sig caliber.

 

[allanh]

I run Gen 4 G27 mags (Follower # 9 and #10) in my G33 with no issues at all.

Sent from my SM-G960U using Tapatalk

 

[tjpet]

I converted a G23 with a LW .357sig barrel years ago using the gun’s .40 mags. I only ran a couple thousand 90gr HPs through it but never had any problems with feeding/ejecting. And the accuracy was superb.

 

[Justamessenger]

I have a G32.3 and an aftermarket barrel, no problems in the one range session using 40 S&W. Is it possible that the direction of the conversion makes a difference? In any event, get a G32, it's a hoot. (And ask him for more mags, that one was a steal!)

 

[1canvas]

Gen3 they are the same gun except the sight height, the Gen4 has a different ejector I was told.

 

[Critch]

"9mm might expand, but a 10mm and 45 ACP will never shrink." Thank you Quantico, my nephew who is a dedicated 45 ACP guy will love that...

 

[Railsplitter]

I bought a barrel to run 357 Sig in my G23. I was using a 40 S&W magazine and everything went fairly well for the first two mags, then every 5 rounds or so the 357 Sig rounds would be tipped down...frustrating.
Saturday I was in my favorite gun store and he had a used Glock 357 Sig magazine, which he sold to me for $5. Not bad. So I went back to the range and shot two magazines and not a single problem...

There must be some subtle differences in the magazines that I don't see....

On another note, not Glock related, I had a brand new Rossi 92 357 magnum lever rifle out there shooting it and it broke after about 40 rounds, the ejector fell out. Brand new rifle. I took it into the dealer this morning and he is sending it off for repair. Oh well...
View attachment 546428

Whatever follower you have just spread the front of the magazine lips slightly. This will allow a greater upward angle for the bullet and provide for better feeding. This has worked for me when I have had "problem" magazines.

 

[Justamessenger]

This needed a comma to convey your meaning. Punctuation matters.

Whatever follower you have, just spread the front of the magazine lips slightly. This will allow a greater upward angle for the bullet and provide for better feeding. This has worked for me when I have had "problem" magazines.

 

[1canvas]

This needed a comma to convey your meaning. Punctuation matters.

Your kidding, right.

 

[Maccabeus]

This looks fun. I haven't been pedantic in days!

This needed a comma to convey your meaning. Punctuation matters.

Why do you assume he meant that?

I'm pretty sure he meant the following:

Whatever, follower, you have just spread the front of the magazine lips slightly. ...

Have I?? And, don't call me "follower"!

Or, maybe it was...

Whatever follower you have just spread, the front of the magazine lips slightly. ...

I hate it when the front of my magazines start lipping. Even if only slightly. It's best not to spread your followers in the first place.

Your kidding, right.

No, my kidding is left here. Right?

I'm not certain of the status of your kidding. Unless you're kidding.


And, now, my apologies. Some take great concern in precise grammar and others of us, find great humor in wordplay and grammar errors; however, most people don't really care and we all know what we all mean. So, here's my contribution to getting back onto the thread topic:

My 40 to 357 conversion (decimals intentionally left out of the caliber designations to annoy the grammarians) :cheers:

S&W uses the same mags for .40 and .357, so I can't comment on the magazine induced feeding problems.