9mm vs 40 feed reliability

[kokapelli]

There was a claim made in another thread that the 9mm has more feeding problems than the 40cal round because of it's shape.

I personally do not shoot 40, but I have never had feeding problems with 9mm through a bunch of different pistols that I have owned over the years and was curious about other people's experience?

 

[CZ9shooter]

I've never had a feed problem my nines that I can remeber. I have limited experiance with 40SW, but did have a minor problem or two in that short window. I dont believe I have enough data to cast a vote though.

 

[kokapelli]

I've never had a feed problem my nines that I can remeber. I have limited experiance with 40SW, but did have a minor problem or two in that short window. I dont believe I have enough data to cast a vote though.

Interesring since you had problems with the 40 with only limited use, but not with the nine with extensive use.

 

[CZ9shooter]

It could have been a bad gun, or a bad batch of ammo. I dont know. A friend's gun and his reloads. So I am not certain that I can call it a problem inherent to 40SW as a whole.

 

[agent109]

I have thousands of rounds fired with S&W.40 ammunition and Glock 40 caliber guns over the years and never seen a failure of any type. I have experienced many loading and extraction failures with 9x19 single stack small guns such as Kel Tec and Ruger and numerous, as in too many to count, in .45 ACP format 1911 firearms. That's my two cents if we are going to revisit the subject. This is my opinion and observations and yours may vary but it does not dismiss mine in any way.

 

[jr_watkins]

Both very reliable

The only time I have ever had feeding issues with either, and it has been the 40S&W, which I shoot 20X more than the 9mm, have been due to me altering my gun(s) from factory configurations. Changing barrels, springs, etc., experimenting basically.

 

[Nom de Forum]

The closest comparison possible is the shooting of both cartridges in the same platform. In my experience the Glock 17 9mmP is insignificantly more reliable than the Glock 22 .40 S&W. So insignificant that I have been entrusting my life to Glock models in .40 S&W since 1990. I shoot Glocks in 9mmP for training in addition to .40 S&W because it is cheaper.

 

[rcmodel]

No difference that I could ever tell.

Out of the three guns in those two calibers I own, I can't ever remember any of them failing to feed.
(S&W Model 39, SIG P6, Glock 23.)

And that covers a LOT of years.

rc

 

[agent109]

Those two old single stack workhorses are a an unfair comparison to the new single stack guns being marketed today. The Sig P6 was a great gun in it's day now the S&W 39 not so much for me.

My opinion is that Kahr has the single stack 9x19 market as it's niche'. That MIT education Justin Moon got seems to have really paid off for him. Interestingly enough,Some agencies are now authorizing the Kahr single stack .40 for duty carry. I am looking to pick up a Kahr CM 40 here real soon to replace my CM 9 for off duty carry.

 

[jmr40]

I like and trust 40 S&W. But I really think the edge has to go to 9mm for reliability. The difference is going to be small, insignificant really. While it may not in fact matter, I'm of the opinion the shape of the 9mm bullets and case is a factor. 40 bullets are flat tipped, almost SWC's with a straight walled case. 9mm bullets are more pointed and the case has a slight taper which I BELIEVE makes it theoretically more likely to feed and eject reliably.

At any rate if quality ammo is used in quality guns you'd probably have to shoot several thousand rounds of each to see any minor differences.

 

[tipoc]

Pretty much the standard for feed reliability is the 9mm. I've never seen or heard of a gun that could not feed it reliably if chambered for it.

On the other hand the 40 feeds well.

Neither has a rep for feeding problems that are traceable to the round.

There was a claim made in another thread that the 9mm has more feeding problems than the 40cal round because of it's shape.

People can make any claim they want, but ya kinda have to be a knucklehead to believe some of 'em.

tipoc

 

[The Lone Haranguer]

If anything, the slight taper of the 9mm Luger case should help feeding and extraction.

 

[kokapelli]

People can make any claim they want, but ya kinda have to be a knucklehead to believe some of 'em.

tipoc

Yes, exactly why I started this pole.

 

[Arkansas Paul]

I have both and can't tell any difference.

The .40 is a Sig SP2022.
The 9mm is a Taurus 709 Slim.

Both are absolutely reliable with both factory ammo and my handloads.
I had a bit of a problem with the .40 at first, but that was my fault. I started applying a taper crimp and the problem went away. No FTFs since.

 

[agent109]

Pretty much the standard for feed reliability is the 9mm. I've never seen or heard of a gun that could not feed it reliably if chambered for it.

On the other hand the 40 feeds well.

Neither has a rep for feeding problems that are traceable to the round.



People can make any claim they want, but ya kinda have to be a knucklehead to believe some of 'em.

tipoc

The reliability issue was raised by me relative to "SINGLE STACK" 9x19 guns. The tapered design of the 9x19 does not lend itself to a continuous presentation angle out of the magazine to enter the chamber. This problem can best be seen by simply laying 8 9x19 on a flat surface and squeezing them together. You will quickly see that they form an arc. S&W engineers discovered this in their development of the model 39 auto-loading pistol. Sig even ran into this phenomenon with the P6. 225 police pistol and both scraped the single stack 9x19 design for a double stack whereas the rounds are forced up into a constant position in the magazine for consistent presentation. Even the Browning Hi-Power stayed away from a single stack magazine design because of this Phenomenon.

Now we have the gun world wanting smaller single stack 9x19 pocket pistols and the tapered design of the 9x19 cartridge once again became an issue regarding feeding reliability and the subject of some of my research study. I met with the folks at Kel Tec in Cocoa Beach Florida regarding this issue and they confirmed that they too were having a feeding problem with the 9x19 single stack pistol they produce which is the PF 9. Their cheap and dirty solution was a flat mag follower and to have increased spring tension pushing up the 9x19 round. Anyone owning a PF 9 can see the situation by simply looking at the grove that will get carved into the plastic follower where the end of the cartridge sits. Eventually the follower will become useless and actually not feed the last round in the mag, This was a trade off for the low cost of the gun and the intended function as to it being a CCW and not meant as a range toy. The entire gun is only rated for a 6 thousand round count life span.

The 9x19 tapered cartridge problem was finally overcome by Justin Moon of Kahr Arms with patented design methods whereas the feed ramp of the barrel if off set to the side and very high tensions in the spring of the magazines. This is why they also make their own and do not import them from Italy as Kel Tec does. Kahr also instructs user to charge the weapon with the magazine release for consistent angle and timing for proper chamber presentation.

The design of the .40 S&W cartridge went back to the old tried and true non tapered casing design when it produced a high pressure round to supplement the shortcomings of the 9x19 round and feeding problems in a single stack design. That was the point I was making that seems to have become offensive to some of the forum elders that are very set in their ways. This is not 1911 anymore and the S&W .40 round is the present culmination of modern design as is the Glock Polymer pistol design that is now being emulated by just about every gun manufacturer. I just read an article whereas Browning will be introducing a new .380 pistol and yes it will have a plastic frame like a Glock.

Welcome to the 21 century folks and the evolution of firearm designs. I remember the old war horse critics spouting their angst for the M16 plastic gun design by Mr Stoner that has become the mainstay of our military. The .40 S&W or 10 mm short is here to stay and in my opinion it has found a well deserved home in the law enforcement community.

 

[kokapelli]

I think the pole results speak for themselves. We had another poster here awhile back that was trying to convince us that the Sig P238 was a flawed design that would never work reliably and we all know how that theory failed and that the P238 is probably the best or at least one of the best micro 380 pistols available.

This pole crushes the claim that the 40 round is more feed reliable than the 9X19.

 

[Walkalong]

The 9x19 tapered cartridge problem was finally overcome by Justin Moon of Kahr Arms

There were a great many 99.99% reliable 9MM pistols long before this. As stated earlier, the taper is a good thing. Certainly not something that had to be "overcome".

 

[Jenrick]

I would argue that the bullet ogive shape has much more to do with feeding in a short shoulderless round like 9mm and .40 S&W. A WC type bullet or even a flat point will be more difficult to reliably coax into the chamber then a round nose bullet regardless of case taper (assuming it's not radically tapered). 9mm rounds tend to have a better ogive for this even in modern HP loadings then .40 S&W, but both seem to load without issue in modern service pistols.

-Jenrick

 

[tipoc]

On occasion intelligent people armed with some knowledge can overthink something and come up with odd results. Like the long distance runners who decided it was better to run a marathon in your bare feet than in running shoes or the folks who decided that shoes are designed wrong and the heel needs to be an inch below the toe. These ideas, elegant on paper, did not stand the test of practice.

The first and obvious problem is that the 9mm was developed for single stack mags and first used in single stack magazines. With great success! George Luger designed it placed it in the gun which bears his name in 1902. A few years later it was adopted by the German Navy then the Army. It was a single stack design. As was the 9mm Mauser pistol which came a bit later. Both these early guns saw international use and distribution.

Then of course there was the Walther P-38. Wait let's see...

Luger P08
Mauser in 9mm
Radom Vis (P35) the outstanding Polish gun.
Sig P210
Walther P38
Colt Commander in 9mm (introduced 1948)
S&W Model 39 and it's descendants.
The original Sig P220 had an 9 round capacity in 9mm.
Sig P225 8 round single stack.

And there are many more all single stack designs.

Around the time the 9mm Luger (aka 9mm Parabellum, 9x19) was introduced a whole slew of 9mm rounds were also developed most of these have passed away. The 9mm as we know it stayed. It was reliable in single stack guns. It's rep was made in single stack mags.

It was a challenge to fit it into a double stack design. Not becasue of the round but because no one had built a double stack mag before. But D. Saive solved that and laid the ground work for what followed in the Hi-Power of 1935.

If Kel-Tec was having problems with feeding in it's guns it was not the fault of the round but of the designers of the magazine and the gun. Similarly with Moon.

tipoc

 

[wally]

My experience says about the same.

My best example is I have a S&W M&P 40C and a 9mm barrel for it. Any differences are fixed by using the proper caliber magazine.

The 9mm ejection is a bit weaker as there is an extra mm of slop in the breech face, but it seems not to matter as ejection still is positive.

 

[agent109]

And I will point out that all those single stack 9x19 guns you cited are no longer in production. Isn't curious how that worked out.

My intention was to share acquired knowledge however, I can plainly see that is not acceptable to the forum senior members. My effort has reached a point of diminished return and that brings the conclusion that enlightenment is unattainable.

The great Albert Einstein concluded that INSANITY was doing the same thing over and over and over and expecting a different outcome!:banghead:

You are the winner! I will discuss my information with a more attentive audience of open minded individuals that can comprehend its concepts. No need to suffer evisceration and obfuscation any longer! Narrow minds never were good learners.

 

[kokapelli]

I guess actual experience means nothing to closed minded people who form an opinion based on flawed theory even though it proves wrong in actual practice.

Kind of reminds me of the global warming crowd.

 

[tipoc]

Agent 109:

And I will point out that all those single stack 9x19 guns you cited are no longer in production. Isn't curious how that worked out.

If you're retiring to find a more "attentive audience" drop by the local gunatorium and ask to see a S&W Shield, the Ruger LC9, Kahr CW9, Sig 239 (the P210 is still in production), Kel-Tec PF-9 and there are other currently produced single stack 9mm guns. The market right now is quite large for concealable single stack 9mms. They work well in general.

If the market is larger for double stack guns in 9mm it is because of capacity not because of problems with the feeding of the 9mm.

tipoc

 

[bangswitch]

There was a claim made in another thread that the 9mm has more feeding problems than the 40cal round because of it's shape.

They're both flat on one end and rounded on the other .

If there is an issue with a particular round feeding or not, I believe it to be the gun's design, or individual condition, and not the fault of the cartridge design. You may get an out of spec cartridge to jam, but that's not in the design parameter.

Feed ramps, magazine spring strength, recoil spring, magazine follower, lots of things can create a feed problem in a particular pistol, regardless of caliber. Maybe a model of one brand might be more temperamental, and several people who all own one and happen to know each other experience occasional mis-feeds. They never have the problem with another brand in a different caliber, so the rumor gets started that XXX caliber doesn't feed as reliably as YYY. In some cases, this might be true, but I think that is what falls into the particular model of gun, and not its specific caliber.

 

[agent109]

I guess actual experience means nothing to closed minded people who form an opinion based on flawed theory even though it proves wrong in actual practice.

Kind of reminds me of the global warming crowd.

There are those that say that you just can't fix stupid either, just saying!