Stovepipe on a Glock .40 with a 9 drop in barrel

J

jasonohio

Inactive
I was shooting this weekend with a 9mm drop in barrel on a Model 22 and I had a stovepipe. I'm thinking it was more limp wristing than the product I was using. Any thoughts?
 
Since the gun is set up for the 40 which has more recoil than the 9mm, stovepipes might be expected. Perhaps a weaker recoil spring will help when running the 9mms.
 
The recoil springs on Glock 9mms and .40s are the same (between equivalent-sized guns). Also, it’s very difficult to limp-wrist a full-sized Glock with normal ammo unless you’re not holding it properly. My guess your stovepipe is due to the fact that the ejector on .40 caliber Glocks is different than on the 9mm ones.
 
The recoil springs on Glock 9mms and .40s are the same (between equivalent-sized guns).
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It depends. On Gen3 or older guns, that is correct. On Gen 4 and newer, things can be different.

A Gen 4 Glock 22 uses a different recoil spring than a Gen 4 Glock 17, for example.

However, your point about there being other differences is correct. There are a number of other differences in the gun between .40 and 9mm that could result in the gun being less reliable when used with a drop-in conversion barrel and no other changes than when used with the original factory barrel in the correct caliber for the gun.

This is why this kind of conversion should ONLY be employed for range use. For self-defense, either a complete conversion should be performed, or the gun should be used with the proper caliber barrel.
 
I've never had an issue with 9mm in my Glock 35 Gen 4 and everything in that is factory.

One stovepipe doesn't make me concerned tho.
 
JohnKSa said:
It depends. On Gen3 or older guns, that is correct. On Gen 4 and newer, things can be different.

A Gen 4 Glock 22 uses a different recoil spring than a Gen 4 Glock 17, for example.
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Thanks for that correction. I completely forgot about post-Gen 3 Glocks. I don’t shoot my Gen 4 anywhere near as much as my Gen 3, so I’ve never replaced the recoil spring on it.

I still agree with you that it’s very likely there are other issues going on than the recoil spring being too light.
 
Is the gun maintained, and properly cleaned and lubed after each use? Do you occasionally strip the slide and give it and its parts a good cleaning?

Are you using 9mm mags?

Are you using factory ammo, or reloads? If its reloads, and the brass is worn, its a pretty common thing.

One stovepipe out of how many rounds too? Stovepipe failures really arent all that uncommon anyway, especially if youre shooting a lot, and/or using less than stellar ammo.

I had a Gen 3 31 with a LWD 40-9 conversion barrel in it, and using 17 mags, other than the reload thing, never had any issues with reliability. I wouldnt have had an issue using it outside of practice.
 
I had a Gen 3 31 with a LWD 40-9 conversion barrel in it, and using 17 mags, other than the reload thing, never had any issues with reliability. I wouldnt have had an issue using it outside of practice.
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I'd advise against it.

Glock has demonstrated in the past that they're willing to go to lengths to make their guns more common with each other. For example, they went to the 3 pin frames in the 9mm pistols even though there was no need to do it from the 9mm standpoint.

But in spite of that, there are still a number of differences besides the barrel when changing from a 9mm pistol to a .40S&W or .357SIG. Those changes aren't there because they're unnecessary. If Glock thought they could get away with making all the parts the same, you know they would.

That's not a guarantee that every Glock shooting with just a conversion barrel is going to be disappointingly unreliable, but they certainly are more likely to have functioning problems than a gun equipped with all the proper parts.

The parts that differ between .40S&W/.357SIG pistols and 9mm pistols of the same size are the following:

Ejector
Extractor
Spring Loaded Bearing
Barrel
Firing Pin
Recoil spring assembly in Gen 4 and later.
 
I understood there were some differences and was kind of expecting problems when I put the 9mm barrel in the gun, but they never developed. The 31 ran as well as my 17's when shooting 9mm, and I put more 9mm through that gun than I did 357SIG.

I think you need to make the decision based on the performance of your gun, and not just the blanket statement you usually get, telling you youre going to have trouble and not to trust it.

Not that you should ignore the possibility you may have a problem either.
 
I've probably shot 1,000 rounds out of my Gen 4 Glock 27 with a 9mm Lone Wolf conversion barrel and 9mm Glock mags (no other changes), and it has been completely reliable.

Anecdotal, I know. But that's been my experience.
 
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I'm not telling you that "you youre going to have trouble"--it's not a guarantee of malfunctions, but it does increase the chances of reliability issues. I am telling you that it is not configured properly for shooting 9mm ammunition. Or, if you prefer, it is only partially configured for shooting 9mm ammunition.

I can certainly see why people would want to shoot 9mm at the range, and also why the increased risk of malfunctions created by using a gun that doesn't have all the correct parts for 9mm wouldn't be an issue when shooting at the range. But reliability is critically important in a self-defense gun. Intentionally using an improperly configured firearm for self-defense, even if it has worked well in the past, doesn't make sense to me. Especially given that nobody shoots enough ammo in a self-defense scenario to make the savings worthwhile.
I think you need to make the decision based on the performance of your gun...
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Unless a person understands the possible failure modes that could result and the number of rounds that each failure mode could take to develop as a result of using each of the improper parts, I think that this is an unwise approach. More to the point, I just don't see what the benefit is.
 
FWIW, unless something has changed since I owned my G22, the .40 slide has more mass/it is heavier. Due to the much greater recoil impulse of the .40 S&W cartridge, less steel is machined away from the slide internally. Even if recoil springs are identical, stovepipes with a 9mm conversion would not surprise me at all. Were it mine, I would try a lighter recoil spring.......ymmv
 
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Yup, that's one of the things I left off my previous list that should have been there.

Here's a revised list:

Ejector
Extractor
Spring Loaded Bearing
Barrel
Firing Pin
Recoil spring assembly in Gen 4 and later
Magazine
The slide is slightly different but a conversion barrel is usually designed to render the slide differences moot.
 
My wife's G23 has been as close to 100% reliable with a 9mm Lone Wolf bbl. as I can remember. We changed out only the bbl. in making the switch but did keep several G19 9mm mags from a previously owned gun for use in the conversion. It does feed & function well with 9mm in the .40 mags

Reliable with the conversion? Well, she's been to Front Sight's 4-day Defensive Handgun Course twice now...that's 600 rounds in 4 days each time without a malfunction of any kind, while using the LW bbl. & 9mm mags. Ammo was American Eagle 9mm 115 gr FMJ with some PMC as well.

All that notwithstanding, JohnKSa's point about CC with a conversion is well taken. When on bedside or purse duty, my wife's G23 is configured for .40 S&W.

Rod
 
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