Help diagnosing M&P fitted barrel malfunctions

[KeeFus]

Yeah, that's what I was afraid of. BTW I noticed that if I slowly ride the slide forward, I can induce this malfunction every time with the fitted barrel and S&B ammo. Doing the same thing with the same ammo and stock barrel, it always goes into battery.

If you can't resolve the issue w/ the 'smith might I suggest a KKM Precision barrel? Over a year ago I bought one of their barrels for my M&P 9 and have had ZERO issues.

Also, Hilton Yam posted a nice lil blog entry about these barrels that may help. http://modernserviceweapons.com/?p=159

[Corvus]

I just received my first KKM drop in barrel for my M&P. Huge improvement in accuracy and functioned perfect at the range. Not enough rounds through it yet to prove anything out but works good so far.

[jumpthestack]

IIRC only one company/person is doing Storm Lake fitted barrels. So if this was done by who I think it was, he isn't a well known gunsmith.

I have seen the results from his barrels and have been tempted to send my latest M&P 9 Pro in, but I think I will continues to wait for Apex's barrels. I just Scott, and Randy much more as they have rather well known gunsmith credentials.

I'm not here to point fingers but yes, it is who you think it is and I would not opt for his services again.

[Dave Berryhill]

...
2) Upon having these issues, I consulted the gunsmith who fitted the barrel, and he said the chamber was set up for 1.10" OAL rounds, and since I was shooting 1.15" OAL rounds, there were problems. He reamed the chamber out further. When I received the barrel back, I still had the original issues, plus now I started having occasional failures to fire(light primer strikes). ....

Chamber reaming length should be done to the proper headspacing length. With a straight-walled pistol cartridge, that length is from the breech face to the shoulder of the chamber. That length doesn't have anything to do with the cartridge OAL or bullet shape, rather it's the case length that matters. Cutting the chamber deeper isn't necessarily the answer unless:
1. the chamber was short to begin with - shorter than a "Go" gauge (or at least close to the minimum length)
2. the new chamber length isn't longer than the "No Go" length.

A chamber that is too long can cause light primer strikes.

The throat or leade of the chamber relates to cartridge OAL since a long cartridge may end up with the bullet making contact with the throat. A special throating reamer can be used to cut the throat longer without changing the headspace. Fortunately, a "standard" chamber reamer made to SAAMI specs with also cut the throat long enough to work with bullets that are similar in shape to GI hardball and most factory ammo so this isn't usually necessary for factory ammo or reloads that are close to factory ammo in bullet shape and OAL.

I'm not saying that your gunsmith cut your chamber too long, just make sure that you guys are on the same page when talking about "cutting the chamber longer/deeper."

[Lomshek]

I'm not here to point fingers but yes, it is who you think it is and I would not opt for his services again.

Reinforces my decision to wait for Apex too. Sorry for your headache.

[Kimura]

2) Upon having these issues, I consulted the gunsmith who fitted the barrel, and he said the chamber was set up for 1.10" OAL rounds, and since I was shooting 1.15" OAL rounds, there were problems. He reamed the chamber out further. When I received the barrel back, I still had the original issues, plus now I started having occasional failures to fire(light primer strikes). This happened about one out of 30 rounds. If I put the round with the light strike back in the chamber, it always fires on the second try. After I started having the light strikes I replaced the recoil spring and striker assembly at which point the rate of light strikes dropped to about one every hundred.


When I switch back to the stock barrel, all the problems go away but the accuracy is also much worse.

Ideas?

Have you spoken with him since you got the barrel back? If you haven't, I would start there. Maybe another gunsmith will be able to fix it, but it won't be for free. If that's ok with you; cool. If not, contact the the guy who did the work and explain to him what's going on. He can't do anything if he doesn't know about the problem. Maybe he'll elect to replace the barrel or maybe not, but he should get the chance to make it right.

Reinforces my decision to wait for Apex too. Sorry for your headache.

It may never come out. That barrel was due a couple of years ago and still isn't out. Last I heard, Randy said that the test barrels don't meet his accuracy expectation. Which is odd considering we're talking about Bar-sto here.

[PPGMD]

It may never come out. That barrel was due a couple of years ago and still isn't out. Last I heard, Randy said that the test barrels don't meet his accuracy expectation. Which is odd considering we're talking about Bar-sto here.

When I last talked to Randy, and Scott (NRA Show) they said that they got some barrels and the feed ramps weren't cut correctly.

[Kimura]

When I last talked to Randy, and Scott (NRA Show) they said that they got some barrels and the feed ramps weren't cut correctly.

So does that mean the barrel is going to be for sale soon or...? That's a very long time from announcement to non release. Are they running into different issues or one issue that they can't solve or... Nothing I've said previously or am saying now should be misconstrued as a criticism of Apex. In fact I admire Randy for holding back the product until it meets his standards.

[EricP]

So does that mean the barrel is going to be for sale soon or...? That's a very long time from announcement to non release. Are they running into different issues or one issue that they can't solve or... Nothing I've said previously or am saying now should be misconstrued as a criticism of Apex. In fact I admire Randy for holding back the product until it meets his standards.

The barrels were addressed in the Apex Tactical newsletter.

Some of you may have heard that the initial batch of barrels was finished and sent to us. This was true, however, the first batch we received did not feed reliably, and the design had to be re-evaluated. Apex requires the utmost in excellence regarding the quality and reliability of our products. Unfortunately, because of these issues, the Bar-Sto Barrels will not be released for an undetermined amount of time. We currently do not have a release date. However we will keep you updated on any new information regarding the arrival of the finished product. When they do become available, they will be for the 4.25" and 5" 9mm M&P's. Fitting services will be available from Apex or you can have them fitted by the gunsmith of your choice. The first batches of barrels will be flush to the end of the slides. Threaded and extended models will be offered in the future.

[jumpthestack]

The person who fitted the barrel has contacted me and is willing to resolve the issue to make sure I am satisfied, so I would like to thank him for following up, and also note that when I was having malfunctions and sent it back to him, he fired some PMC 115gr, UMC 115gr, and Magtech 115gr, 50 rounds in total with no malfunctions. Also, I later sent the barrel by itself to Storm Lake to see if there was anything they could do with it, and they reamed the chamber a little more and said that the chamber was in spec, but the malfunctions persisted when I got it back.