Caliber swap with factory barrels

This is a discussion on Caliber swap with factory barrels within the MP Full Size Pistols forums, part of the Smith & Wesson MP Forum category; So, if I read through the other posts correctly...I can buy a M&P40 and a S&W factory 9MM barrel (and 9mm mags) and have a ...


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Old July 23rd, 2012, 04:56 PM   #1
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Caliber swap with factory barrels

So, if I read through the other posts correctly...I can buy a M&P40 and a S&W factory 9MM barrel (and 9mm mags) and have a 2 caliber gun? The dimensional differences between the 40 and 9mm barrel are slight enough not to drastically affect accuracy or functioning/reliability?
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Old July 23rd, 2012, 05:21 PM   #2
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Yes, I hav e a 9mm S&W barrel on backorder from Midway for 66.99 plus shipping, and I'm hoping I am not too far back on the list to get one the next time they get a shipment in. They say 8/10 (8/03 for the .357 Sig barrels -- but I can only afford one at a time, so I' m going for the one that will actually save me money first). The .357 is even easier to use than the 9mm, since the mags are the same, and the .40 mags can jam on the last bullet with 9mm. (Midway's prices are 77.99 for .357 and 88.99 for .40 barrels)
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Old July 23rd, 2012, 05:28 PM   #3
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Storm Lake Barrels & KKM Precision make both replacement 9mm and 9mm conversion barrels.

An OEM 9mm barrel and any 9mm replacement will not lockup in an M&P40 or 357 the same as a conversion barrel, I would not call it safe.

I think anyone who would use a 9mm barrel other than a conversion barrel in a 40/357 is a complete friggin idiot.

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Old July 23rd, 2012, 05:46 PM   #4
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You might want to check the threads on the Smith and Wesson forum, which not only include many posts from people who have done the drop in with factory barrels as well as the results of measurements by micrometer to verify the lockup on the 9 mm barrel in the .40 before you call anyone " a friggin' idiot" -- an "ad hominem" attack, please!

Many have safely run hundreds of rounds, some thousands of rounds -saving not only the difference between .40 cal. and 9 mm ammo, but also the difference between a $ 66.99 factory barrel and a $150 to $ 200 StormLake barrel.

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Old July 23rd, 2012, 06:16 PM   #5
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Quote:
Originally Posted by bobnieder View Post
You might want to check the threads on the Smith and Wesson forum, which not only include many posts from people who have done the drop in with factory barrels as well as the results of measurements by micrometer to verify the lockup on the 9 mm barrel in the .40 before you call anyone " a friggin' idiot" -- an "ad hominem" attack, please!

Many have safely run hundreds of rounds, some thousands of rounds -saving not only the difference between .40 cal. and 9 mm ammo, but also the difference between a $ 66.99 factory barrel and a $150 to $ 200 StormLake barrel.
Defending a questionable action with suggestions alluding to checking information on an forum doesn't give me any confidence in another persons position.

Contact S&W, I have, ask them about running an OEM 9mm barrel in a 40/357. I have also contacted Storm Lake regarding use of their 9mm replacement barrels vs their 9mm conversion barrels in a 40/357. Should I also inquire with KKM?

Needless to say none of them are going to honor a warranty under conditions wear a standard 9mm barrel is used in a 40/357 let alone assume any liability.

I started my first post before the one quoted above was posted, it wasn't directed at any particular person, but if someone takes it as an attack, then so be it.
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Old July 23rd, 2012, 06:57 PM   #6
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Ok, since you' re taking the warranty road here, what about the aftermarket mods, including Apex Tactical trigger mods. Are you going to extend your "friggin'idiots" umbrella to cover allof us who have modified our M&P's with these products? What are the boundaries? Because Smith is unwilling to stand behind a combination of their own parts, in a configuration that they use every time they manufacture a 9 mm M&P -- does that even make sense to you? Check the part numbers -- the slide, the recoil spring, the trigger loop, the sear block, in fact every single part in the pistol, except the mags and the barrel, is exactly the same in the .40 and the 9 mm. The .357 only differs from the .40 in the barrel. S&W built the .40 first, it was the prototype, and they gave it enough headroom to handle the higher pressure of the .357, and the 9 mm was an easy step same OD barrel, different bore -- they had already done it with the .357 -- add a mag designed for the smaller 9 mm round, and voila! 9 mm!

I've already expended more energy on this than it's worth. It's really a pretty simple issue. It's not like I'm advocating using Acme Noname 9mm barrels -- they are factory S&W barrels. Of course, I suppose all the people who have posted are lying or delusional -- as are the reviewers on Midway's site that relate that they are pleased with how easily the barrels were to use and how well they functioned.

I am done. You can now sit back and wait for the report of an M&P KABOOM! and for me to say, "If only I had llistened . . . But . . . It's not gonna happen!
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Old July 23rd, 2012, 07:24 PM   #7
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I can guarantee the slides ARE NOT the same between the 40/357 and the 9. Try putting a M&P40 or M&P357 barrel in an M&P9. Try it, then come back with a full report. I'll have a nice hot plate of crow waiting.
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Old July 23rd, 2012, 10:08 PM   #8
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Quote:
Originally Posted by bobnieder View Post
results of measurements by micrometer to verify the lockup on the 9 mm barrel in the .40
The guy who made those measurements intentionally left out measurements that didn't prove his point, setting up folks for a potential failure. Shame on him for doing that, and for repeating it here.

The 9mm factory barrel does NOT lock up properly in the 40 slide and it has contributed to multiple failures including early unlock and cracked/broken barrels.
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Old July 24th, 2012, 08:07 AM   #9
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Originally Posted by KRWeiss View Post
The guy who made those measurements intentionally left out measurements that didn't prove his point, setting up folks for a potential failure. Shame on him for doing that, and for repeating it here.

The 9mm factory barrel does NOT lock up properly in the 40 slide and it has contributed to multiple failures including early unlock and cracked/broken barrels.
Perhaps that was the post I saw here or on the S&W forum, I know it was someone saying the had mic'd out everything and there was only a few thousandeths differences in a few places. You are saying this is not correct? and the aftermarket caliber swap barrels are the better choice, albeit more expensive.
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Old July 24th, 2012, 08:26 AM   #10
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... there was only a few thousandeths differences in a few places. You are saying this is not correct?
Not just incorrect, it was a deliberate deception.

Quote:
... and the aftermarket caliber swap barrels are the better choice, albeit more expensive.
If S&W made a factory 9mm conversion barrel it would sell for well under $100. Unfortunately they don't, so we have to rely on the match grade aftermarket for 9mm conversion barrels, and match grade is always more expensive.
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Old July 25th, 2012, 07:58 AM   #11
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The 9mm factory barrel does NOT lock up properly in the 40 slide and it has contributed to multiple failures including early unlock and cracked/broken barrels.
I havnt seen info on this. Do you know where the cracks or breaks are happening?
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Old July 25th, 2012, 01:24 PM   #12
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All were the previous barrel design, as far as I know they all broke right at the notched ring (haven't seen pictures of every one and descriptions vary). By my count at least 9 M&P9 barrels have broken, 4 of those in a 40 slide. I doubt the percentage of folks using a M&P9 barrel in an M&P40 slide covers that spread.
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Old July 25th, 2012, 02:02 PM   #13
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SW-MP-9MMC-425
$121.82 + $5.99 Flat Rate S&H ($127.81)

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Old July 30th, 2012, 06:52 AM   #14
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'splain it to me Lucy

I too am interested in this topic, as I am considering such a purchase, so will jump in here with my comments.

I have read a lot of reports from many users in several different forums, that have used the stock OEM 9mm barrel in their 40 S&W without any reported issues. I have not read one reported failure or comment of it not fitting or working properly.
Several people who bought the aftermarket brand barrels have reported multiple issues, from not fitting at all to FTE/FTF and other problems, some requiring multiple trips back to the manufacturer.

There have been more than one person who posted comparative dimensions between stock S&W 9mm & 40 barrels, showing the close dimensional similarities. It appears that most dimensions are within a couple of thousandth's. I said "close" because we must realize of course that there are going to be some measurement variances due to manufacturing tolerances, equipment used and the skill of the person measuring their sample barrels, however the dimensions reported are close enough to being the same as to convince many such as myself, that it will work just fine (who are not experienced gunsmiths in what is/is-not acceptable dimensional tolerances/differences for acceptable barrel fitment).
I have not found any comparative dimensions from owners of aftermarket barrels.

The only negative comments I've seen have been unsupported statements like the ones in this thread. The naysayers commonly just say it won't work and might cite lockup issues but I cannot find any statement indicating where exactly the incompatibility or critical dimensional difference is. I looked up that broken barrel thread and can't see where it relates to using a 9mm barrel in a 40 slide. I would initially say that there was another type of material failure.

When an unknown poster on another forum has supposedly provided supporting facts to their opinion, calling them an idiot or that they were intentionally deceptive, without stating opposing facts makes the name calling and subsequent opinion totally irrelevant in my book. It takes any credibility I had from the dissenting poster and makes me wonder if they have a connection with one of the barrel makers or other vested interest in steering people away from the OEM product.

To help me (and others) understand this issue, I have a couple specific questions I would like answered from those who (act like they) know the facts.

1. What or where is the dimensional incompatibility between the S&W OEM 9mm & .40 barrels that make a 3rd party product necessary for conversion purposes. Don't just cite lockup, explain the lockup process coherently in detail - what, where and why.

2. What are the critical dimensional differences of a 3rd party barrel from the OEM product that are required for conversion compatibility. (Please note if the design difference is related to only for avoiding patent infringement).

3. What are generally accepted tolerances in the various critical areas?

There are many people here who have multiple versions of M&P pistols and some with aftermarket barrels. I suspect there are bonafide pistol-smiths and qualified machinists among us who could answer these questions without a lot of trouble. In my searches, I had hoped that by now, someone with the skill and resources to provide a definite, in-depth answer to this long running and often asked question, would have done so by now. It doesn't look like anyone has. Any takers to this challenge??

So far, I have not seen any real reason not to buy a S&W barrel.

At least over on the XD forum they can tell you that the hole in the end of the .40 slide is too big to allow a stock 9mm barrel to lock up properly and you need a conversion barrel because of the larger diameter.

SG

Last edited by SyberGunner; July 30th, 2012 at 07:06 AM.
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Old July 30th, 2012, 06:58 AM   #15
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I too kept getting conflicting answers. So I emailed S&W directly and asked. Here's the email and replies.
~~~~~~~~~~~~~~~~~~~~~

Hi Stromm
Sorry for the confusion and that would be no to your other questions
Tom

-----Original Message-----
From: [mailto:]
Sent: Thursday, July 26, 2012 5:02 PM
To: Rivers, Tom
Subject: Re: M&P9/357/40 barrel swaps?

Hi Tom,

That answers one of my questions...

Not intending to be rude, but what about the other questions?

Sent from my iPad

On Jul 26, 2012, at 4:22 PM, "Rivers, Tom" <trivers@smith-wesson.com> wrote:

Hi Stromm
You can buy a M&P 357 sig barrel for a M&P 40 cal.
Best regards Tom

-----Original Message-----
From: [mailto:]
Sent: Wednesday, July 25, 2012 6:19 PM
To: Smith & Wesson Support
Subject: M&P9/357/40 barrel swaps?

Please settle a debate going on over at MP-Pistol Forum.

I own a M&P40 (love it too, almost 2000 rounds thought it in six months and not a single issue).

Can I buy a standard M&P9 barrel and magazine and safely use them in my M&P40 frame and slide?

Can I buy standard M&P357 barrel and safely use it with my M&P40 frame, slide and magazine?

If I owned a M&P9, could I safely use a standard 40 or 357 barrel with its frame and slide?


Thank you very much for officially clarifying this debate.

Sent from my iPad
~~~~~~~~~~~~~~
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Old July 30th, 2012, 07:20 AM   #16
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Thanks Stromm,
Is this Tom a Customer Service Rep type or an Engineer, machinist or GunSmith type at S&W?

It does add an official stamp of disapproval to the question - and my mind isn't made up one way or the other on the issue, but as the doubting Thomas I sometime am, I currently suspect he is preaching the official party line.

The OEM is naturally one of the first places to ask, but for various reasons the CS rep may not know the answer or may have been instructed to provide a specific answer. Sometimes to find the truth you have to find out in other ways and since there are so many people successfully doing it, I suspect this may one case where engineering proof is required to convince people like me. mathematics are impartial.

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Old July 30th, 2012, 09:23 AM   #17
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It's seems the conversation has changed from "is this safe" to more of a "you're a liar" kinda thing. Since SG has questioned everyone's motivations with words like "naysayer", "unsupported", "irrelevant", "preaching" and attacking my credibility (tactics which he also specifically decried) I would like to interject the fact that I have no financial, official, professional, or personal connection to any of these companies (except possibly APEX Tactical) and that the offending barrel/slide measurements and their effects have been documented and discussed numerous times in these forums.

In short, the breech locking lug, and tightly matching recess in the slide, are narrower by design on the M&P9mm than the M&P40 or M&P357 to keep folks from using heavier recoiling 40/357 rounds with the slightly lighter 9mm slide (40/357 breech locking lugs are identical, which is why S&W specifically states the factory M&P357 barrel is perfectly acceptable in the M&P40 slide (i.e. "You can buy a M&P 357 sig barrel for a M&P 40 cal.", which defeats another one of the common arguments... corporate greed) but not the factory M&P9 barrel in the M&P40/357 slide or a M&P40/357 barrel in a M&P9 slide (as in "that would be no to your other questions"). This additional gap at the breech locking lug allows the barrel to snap more violently to the left as a result of the bullet being accelerated to the right as it travels down the barrel (Newtons third law, equal but opposite reaction). Under less than ideal circumstances this snapping action is characterized by the entire barrel accelerating momentarily to somewhere around 10,000 rpm before the chamber is abruptly halted a couple/few 10,000ths of a second later by the smaller M&P9 breech locking lug slamming into the left side of the larger 40/357 slide recess. This can and will cause out of spec stresses on the barrel and slide.

This same action can reduce, and in some cases eliminate, the static friction which keeps the bullet casing/breech face "stiction zone" from releasing, allowing the chamber to unlock under pressure, the very definition of early unlocking.

These are two fairly simple concepts, by no means a complete discussion, the ramifications of which are not easily understood by many firearm enthusiasts. Since this subject is not commonly discussed on the internet (for obvious reasons), folks who's investigative ability, knowledge and/or "authority" is strictly limited to the internet may conclude that they simply don't exist (or are irrelevant).

Edit: Spelling, clarification.

Last edited by KRWeiss; July 30th, 2012 at 10:45 AM.
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Old July 31st, 2012, 04:37 AM   #18
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It has now...

KRWeiss... Thanks for your detailed reply on the lockup mechanics during firing. It is something to consider and is a good start to finding a reasonable answer to the question and it is exactly the type of thing I have unsuccessfully searched the web (and this forum) to find.

I am typically skeptical of generalized non-technical internet answers and usually do not accept them at face value without some kind of rational data that can be cross checked or verified. Not to call you a liar, but as a subject oriented comment, I have not been able to find any similar detail as you say, in other threads. I would appreciate if you could point me to some of these threads you mentioned?

I'm sure you'll correct me if I'm wrong, so bear with me as I digest this in my own words and try to understand what I think you are saying, I can see I will have to be wordy to try and not step on any toes.

o- you said (in so many words) that the breech locking lug and corresponding slide recess are intentionally smaller on the 9mm to prevent using a 40/357 barrel being used in a 9mm slide, because it is lighter. By breech locking lug, I assume you are talking about the protrusion at the rearmost top of the chamber block, that also contains half of the "loaded chamber inspection port").

So, are you saying that the dimension of the breech locking lugs are different widths and that it is one of the critical dimensions I ask about?

You also stated that the 9mm slide is lighter than the 40/357 slide. Is this is another critical reason? Since they both use the same lower and same recoil spring, I infer then that the 9mm slide somehow can't handle the additional torque of a cartridge designed for only 5000 more psi.

At first, that sounds like a plausible explanation to prevent a reverse caliber swap, but wouldn't also the fact that the 9mm slide's breech face-cut is narrower and won't allow the larger 40/357 cartridge to fit or fire be a sufficient deterrent too?

On the other hand, the 9mm barrel will fit in a 40 slide. If it's now an unsafe combination, I wonder why they didn't make some other change to prevent it from working at all, like maybe changing the bottom locking lug size or barrel diameter, etc.

On a side note, back in the 80's or 90's when S&W changed the top locking lug width (aka hood) on 3rd gen barrels there was a noticeable difference in size - almost 1/8" gap was obvious.

It seems strange they would limit this one to a only few thousands and expect everyone to know not to swap it. hmmmm Sorry, but I don't buy this line of.... reasoning.

As for the 'corporate greed' comment, I agree with you that S&W does not exhibit any signs nor has any reason to use that as an answer to the question. However a more likely reason would include concepts of corporate liability and increased product support issues. I believe their CS reps more than likely have a playbook to answer most common questions according to corp. policy as set by higher ups.

o- Your next concept statement focuses on the rotational torque during firing and bullet acceleration. Truly a mind boggling series of events in a short time period if you stop to think about it, which most people don't. You described it magnificently and it fits well with your initial reasoning, and really is a believable concept that sets the issue to rest.
However I am still a little skeptical and need to think out loud a little more....

I suppose you want me to focus attention on the top locking lug and forget that the chamber block is a large rectangle, locked snugly into the slide cutout with a very large non-rotational bearing surface on that critical left side. Also that the bottom locking lug has no role (although it has a larger side surface area than the breech lug and is attached to the frame, and also the slide stop pin and any other barrel/frame contact points should be ignored. I gather I should also believe that a couple thousands side play at the breech locking lug is going to let the barrel start spinning for a fraction of a second before this small block hits the breech recess to absorb all of this force. If this were true, then there should be some evidence we can find, such as a rub mark or battering on a contact surface.

It just so happens that I have borrowed a OEM 9mm barrel to try out in my 40. I don't know how many rounds have been put thru it, but I have shot a couple hundred rounds out of it. Looking it over very closely, I cannot find any rub marks or any type of shiny friction surface anywhere on it (except of course the feed ramp and barrel). Everything still looks like new... the left and right chamber block, lower locking lug, slide pin recess, entire barrel length, top locking lug - all sides.... Oh wait, there is a slight rub in the finish on the barrel unlocking ramp (the same mark found on a 40 barrel). So once again, while your reasoning sounds good it just doesn't quite pass the smell test for me.

With all this precision required it's a wonder the 1911 worked without being mud-packed.

o- I'm going to pass on commenting about the breech 'stiction zone' and early unlocking as I need to do more research to understand it better. I was under the impression metal surfaces had to be super precise like gauge blocks in order for that phenomena to occur. I would have thought that a case/breech is too rough a surface, but then I'm new around here, what do I know?

I can see that having a rational discussion on this topic is not going to work. So overall, I say nice try, it all sounds good on the surface, but I'm not buying your BS answer.
..........
Now back to the first paragraph of your comments and the mud slinging ...

In my original post I tried to relate the overall information I have seen posted from several sources, in a generalized manner, not dwelling on just one persons opinion. I said that there are numerous positive reports and dimensional comparisons to support the use of the OEM barrel and that opposing opinions (that contend it won''t work) usually don't cite any rational facts that can be backed up, thus the use of descriptive terms such as "naysayers" and "unsupported". I said posts like these are "irrelevant" to me as answers.
I was only presenting a background for asking a specific question. You then take them out of context trying to twist them into an example of negativism toward your credibility, so you can go on the attack.

I never insinuated or called you a liar but I do take exception to your elitist attitude. You seem to have a hair trigger temper and read things between the lines where there is nothing there directed at you. You also like to manipulate what others say in a self serving manner.

Just so you don't have to strain your narrow eyes, I'll make it plain... I think your full of bullsh*t and like to throw your opinions around as the local hotshot, if that doesn't work you become overbearing and go on the attack to intimidate.

Now we're done, rant at me all you want, I've got better things to do than argue with you... I've already wasted all the time I'm going to on this subject.

To everyone else... As to the use of a factory barrel or aftermarket conversion barrel, use whatever you feel is best. After stepping thru the above sequence I have come to the conclusion that the couple thousandths difference in the width of the breech hood doesn't make any noticeable difference for my purposes.

I'm not recommending you use one but until I see evidence of it being unsafe or an official written position from S&W, I think the oem barrel is good enough for range practice.

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Old July 31st, 2012, 07:02 AM   #19
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Originally Posted by SyberGunner View Post
KRWeiss... Thanks for your detailed reply on the lockup mechanics during firing. It is something to consider and is a good start to finding a reasonable answer to the question and it is exactly the type of thing I have unsuccessfully searched the web (and this forum) to find.

I am typically skeptical of generalized non-technical internet answers and usually do not accept them at face value without some kind of rational data that can be cross checked or verified. Not to call you a liar, but as a subject oriented comment, I have not been able to find any similar detail as you say, in other threads. I would appreciate if you could point me to some of these threads you mentioned?

I'm sure you'll correct me if I'm wrong, so bear with me as I digest this in my own words and try to understand what I think you are saying, I can see I will have to be wordy to try and not step on any toes.

o- you said (in so many words) that the breech locking lug and corresponding slide recess are intentionally smaller on the 9mm to prevent using a 40/357 barrel being used in a 9mm slide, because it is lighter. By breech locking lug, I assume you are talking about the protrusion at the rearmost top of the chamber block, that also contains half of the "loaded chamber inspection port").

So, are you saying that the dimension of the breech locking lugs are different widths and that it is one of the critical dimensions I ask about?

You also stated that the 9mm slide is lighter than the 40/357 slide. Is this is another critical reason? Since they both use the same lower and same recoil spring, I infer then that the 9mm slide somehow can't handle the additional torque of a cartridge designed for only 5000 more psi.

At first, that sounds like a plausible explanation to prevent a reverse caliber swap, but wouldn't also the fact that the 9mm slide's breech face-cut is narrower and won't allow the larger 40/357 cartridge to fit or fire be a sufficient deterrent too?

On the other hand, the 9mm barrel will fit in a 40 slide. If it's now an unsafe combination, I wonder why they didn't make some other change to prevent it from working at all, like maybe changing the bottom locking lug size or barrel diameter, etc.

On a side note, back in the 80's or 90's when S&W changed the top locking lug width (aka hood) on 3rd gen barrels there was a noticeable difference in size - almost 1/8" gap was obvious.

It seems strange they would limit this one to a only few thousands and expect everyone to know not to swap it. hmmmm Sorry, but I don't buy this line of.... reasoning.

As for the 'corporate greed' comment, I agree with you that S&W does not exhibit any signs nor has any reason to use that as an answer to the question. However a more likely reason would include concepts of corporate liability and increased product support issues. I believe their CS reps more than likely have a playbook to answer most common questions according to corp. policy as set by higher ups.

o- Your next concept statement focuses on the rotational torque during firing and bullet acceleration. Truly a mind boggling series of events in a short time period if you stop to think about it, which most people don't. You described it magnificently and it fits well with your initial reasoning, and really is a believable concept that sets the issue to rest.
However I am still a little skeptical and need to think out loud a little more....

I suppose you want me to focus attention on the top locking lug and forget that the chamber block is a large rectangle, locked snugly into the slide cutout with a very large non-rotational bearing surface on that critical left side. Also that the bottom locking lug has no role (although it has a larger side surface area than the breech lug and is attached to the frame, and also the slide stop pin and any other barrel/frame contact points should be ignored. I gather I should also believe that a couple thousands side play at the breech locking lug is going to let the barrel start spinning for a fraction of a second before this small block hits the breech recess to absorb all of this force. If this were true, then there should be some evidence we can find, such as a rub mark or battering on a contact surface.

It just so happens that I have borrowed a OEM 9mm barrel to try out in my 40. I don't know how many rounds have been put thru it, but I have shot a couple hundred rounds out of it. Looking it over very closely, I cannot find any rub marks or any type of shiny friction surface anywhere on it (except of course the feed ramp and barrel). Everything still looks like new... the left and right chamber block, lower locking lug, slide pin recess, entire barrel length, top locking lug - all sides.... Oh wait, there is a slight rub in the finish on the barrel unlocking ramp (the same mark found on a 40 barrel). So once again, while your reasoning sounds good it just doesn't quite pass the smell test for me.

With all this precision required it's a wonder the 1911 worked without being mud-packed.

o- I'm going to pass on commenting about the breech 'stiction zone' and early unlocking as I need to do more research to understand it better. I was under the impression metal surfaces had to be super precise like gauge blocks in order for that phenomena to occur. I would have thought that a case/breech is too rough a surface, but then I'm new around here, what do I know?

I can see that having a rational discussion on this topic is not going to work. So overall, I say nice try, it all sounds good on the surface, but I'm not buying your BS answer.
..........
Now back to the first paragraph of your comments and the mud slinging ...

In my original post I tried to relate the overall information I have seen posted from several sources, in a generalized manner, not dwelling on just one persons opinion. I said that there are numerous positive reports and dimensional comparisons to support the use of the OEM barrel and that opposing opinions (that contend it won''t work) usually don't cite any rational facts that can be backed up, thus the use of descriptive terms such as "naysayers" and "unsupported". I said posts like these are "irrelevant" to me as answers.
I was only presenting a background for asking a specific question. You then take them out of context trying to twist them into an example of negativism toward your credibility, so you can go on the attack.

I never insinuated or called you a liar but I do take exception to your elitist attitude. You seem to have a hair trigger temper and read things between the lines where there is nothing there directed at you. You also like to manipulate what others say in a self serving manner.

Just so you don't have to strain your narrow eyes, I'll make it plain... I think your full of bullsh*t and like to throw your opinions around as the local hotshot, if that doesn't work you become overbearing and go on the attack to intimidate.

Now we're done, rant at me all you want, I've got better things to do than argue with you... I've already wasted all the time I'm going to on this subject.

To everyone else... As to the use of a factory barrel or aftermarket conversion barrel, use whatever you feel is best. After stepping thru the above sequence I have come to the conclusion that the couple thousandths difference in the width of the breech hood doesn't make any noticeable difference for my purposes.

I'm not recommending you use one but until I see evidence of it being unsafe or an official written position from S&W, I think the oem barrel is good enough for range practice.

What's your point? KR has been suggesting that it is the safe way to get a conversion barrel. If that wasn't the case a conversion barrel wouldn't be made.
Please don't offer (your opinion ) when the experts say other wise. It has been post on here (don't ask for a link just find it or don't. I don't care) that storm lake who makes the barrels think there is enough of a risk to out whiegh the manufacturing cost. Thanks.
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Old July 31st, 2012, 07:55 AM   #20
TOF
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Dang, where's the Red Bull when you need him?

Everybody listen up: You need to post your Certified Barrel Engineering Degree prior to injecting comments in this thread.

Those without said degree should remember: Because it can be done does not mean it should be done. (quote borrowed form someone)
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