Had an interesting trip to the range last night. Took my 6906 planning to run a box of WWB through it. On my second magazine I had a FTE. I have never experienced any kind of failure with this gun so I was quite surprised. Next round, same thing. Now I was really puzzled. On the next round the slide froze halfway back. My friend took the gun home as he is vastly more experienced than I. He called me later and said the barrel had a bulge in it and that inside it was obvious where the rifling had started to part. I was shocked. Anyway, I now need a new barrel for my 6906. In searching around the net I saw one at an auction site and it said it was one of the "older models with hood". Are there different barrels? I would think that if there was an engineering change that they would have a dash one, etc. I love my Smith and I want to get it back in shape ASAP. Could someone with knowledge of this please school me so that I don't waste money on the wrong barrel. Thanks in advance,
BA

That is an interesting problem. Don't know about the"hood" question, but can you post a picture and hopefully someone will comment.
Also, while I think I saw that the S & W factory is closed for the holidays, you might want to call them and see if they can help, as it seems that might be a warranty item and I would think they still have those barrels.
Good luck.

I'd wait to talk to S&W next week.

There are a couple of issues to consider when replacing barrels in older 3rd gen guns, especially those with aluminum frames.

First, a replacement barrel has to conform to the same slide/breech face design. The older guns had what are called narrow breech face cuts, with corresponding narrow barrel tabs (the rear of the hood). Newer slides had wide cut breech faces, often called straight cut slides, and the barrels had wider tabs to fit the wide breech face cuts.

The narrow cut slides had the breech faces machined to form curved 'shoulders' right above the top of the chambered case, so the cut above/between them was narrow. This narrow cut extended up to where the barrel tab met the breech face.

The straight cut slides eliminated the curved breech face shoulders, making the 'machined cut' wider (straight) and continuing upward to where the barrel tab met the breech face. (They changed the extractor spring tension spec a bit at the time of the machining change, as well.)

So, a narrow cut breech face requires a barrel with a narrow tab, and the straight cut breech face requires a barrel with the wide tab.

Now, as the barrel cam lugs (on each side of the feedramp) run up & down within the frame cuts during unlocking & locking, they can develop peening and wear patterns in the frame which may interfere with a different barrel dropping in and functioning properly. Just depends on the barrel and the frame combination in any particular gun.

I tried to put a different (used) slide & barrel onto a different (used) 6906 frame one time. The slide wasn't a problem, but the different barrel just wouldn't run & hand-cycle smoothly within the well-used frame. The barrel lugs just wouldn't run down & up the corresponding spots in the frame. I ended up having to use the barrel which had been used with that frame, in the "new" slide, although it did require some fitting to work with the "new" slide. This involved some adjustment of the barrel hood & tab, while still maintaining proper tolerances.

It's really best left to a factory tech, gunsmith or armorer familiar with the older 3rd gen guns. (Some newer armorers may have never been in the position of having to replace a barrel, because the newer production guns have pretty much made it a situation where new barrels and slides require less fitting - or no fitting - than might have been needed with older guns.)

Besides, the factory repair tech will have more than one barrel available to try and fit to a particular slide & frame, so he can probably more easily try to find one which will fit and function better in your frame, using your slide, with whatever minor fitting may be necessary. (Of course, I'm speaking in generalities, as I have no way of knowing if they have many - if any - barrels of the different production styles of the 3913/6906 barrels available for repair at this time. You'll have to call and ask.)

It's important to have the barrel fit the slide, as well as move and function as intended within any particular frame. Smoothness and freedom of proper movement is critical to safe, optimal operation of the pistol.

FWIW, the condition and shape of the top of the frame cuts (which create the release point for the barrel to be lifted and moved into battery with the slide) are critical. If they become damaged, or go out-of-acceptable spec, the frame becomes useless and you can find yourself needing a new gun. I knew another armorer who had that happen with an older 4013 (made on the .45 alloy frame). They examined the gun and told him it was no longer safe to use, but since he was the original owner they replaced that gun with a new/different model (since no more 4013's remained available).

Just my thoughts, but I'd discuss this with the factory before spending any money on a barrel purchased elsewhere - and I'd let someone familiar with the guns, and experienced in making repairs, examine the gun and do the work.

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Ret LE Firearms inst & armorer

I wholeheartedly agree with fastbolt on this! Let S&W take care of this one....
Randy

Thanks that sounds like very good advice. I appreciate it very much.

Wow. Thanks for the info.

If I am to understand this correctly that means used 3rd Gen pistols basically need to have their barrels custom fit to the frame at the factory if a replacement is needed?

Not exactly. It's just that they aren't really "drop-in" parts in each and every pistol.

Also, since the aluminum frames can develop peening inside the angled cuts where the barrel lugs ride (in a way that the steel frames wouldn't normally develop, steel being harder than aluminum), sometimes the extent of the wear inside the aluminum frames may complicate things.

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Ret LE Firearms inst & armorer

Does anyone have a ballpark figure on what it costs to have something like that done at S&W? It was a $360 gun so there is a limit of how much I would want to sink into it. I love the gun but I am not sure I want a thousand dollar 6906.

S&W may just do it for you for free. Send it to them. See what they say..If they can't fix it then they may offer you a new M&P as a replacement.. S&W customer service really is that good!!

As a third gen. gun it should be under warranty...
Randy

You'd have to call and see if they'd cover it under warranty or not.

If the barrel was damaged due to an unnoticed obstruction (squib), and/or you're not the original owner, and/or the gun was sold before they started to offer the lifetime warranty to original commercial owners ... then the barrels are listed at about $125, plus shipping & whatever labor is involved.

Dunno. Call next week and ask.

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Ret LE Firearms inst & armorer