Zero issue with S&W M&P 340 (J Frame)

[HCM]

I’m having a zero issue with my S&W M&P 340. It’s the model with the factory XS Big Dot Front sight and Laser grips.

I purchased this weapon from a S&W Law Enforcement dealer with the intention of getting it approved for duty use as a back-up weapon to replace my S&W 642.

The M&P revolver functions and groups fine, however. at 7, 15 and 25 yards it consistently hits to the right / 3 o’clock. The group moves further to the right as the distance increases. Approximately 3” at 7 yards, 6 “ at 15 yards , 8-10” at 25 yards etc.

The first time I fired the 340 I used Remington lead free Frangible . I thought the zero issue might have been the lead free ammo so tried with our duty round, CCI/Speer 135 grain +P .38 special as well as Remington and Winchester standard velocity 130 grain FMJ .38 special.

To eliminate the possibility this was shooter error, I shot the same ammunition through my S&W 642. The groups were centered with all three types of ammunition. I then tried dry fire with the laser grips and saw no pronounced movement to the right. Finally I had another experienced shooter/ Firearms Instructor shoot the 340 – all rounds were to the right for the second shooter as well.

I contacted S&W customer Service, they sent me a fed ex label and the 340 went back to S&W. A few weeks later the 340 was returned. the work order read : “Customer Complaint – Barrel Frame Line-Up” and “ Repaired Adjust Barrel Alignment.”

I took the 340 out to the range last Friday and it is still hitting consistently to the right with CCI/Speer 135 grain +P . I again had a second experienced shooter fire the weapon and again all rounds were to the right for the second shooter as well as myself. The barrel / front sight appeared to be centered.

S&W is sending another Fed Ex label but any thoughts / suggestions on cause and possible solutions would be appreciated.

.

[Failure2Stop]

You know you can zero the lazer, right?

[HCM]

Yes, Im aware, Thanks. I 've zeroed the laser however I'm a little old school and not comfortable relying on the laser 100 %. The more visible big dot sight was a a big selling point for me since I'm not allowed to utilize the laser for agency quals. We are prohibited via policy from using WML / laser combos but laser grips are a grey area - since these are factory installed I can get by with them policy wise.

[Failure2Stop]

Sounds like you zeroed it at a close distance and are experiencing the difference in beam/trajectory intersection.

I zero mine at 25 yards.
Would have done 50, but lighting conditions didn't work out for me.

Typos brought to you via Tapatalk and autocorrect.

[HCM]

The zero issue / hitting right is with the iron sights ( sorry if that was unclear in the original post.)

[JBRIII]

Have you tried 158's? Mine was consistently shooting low with 125 or 135's, but switched to Buffalo Bore 158 +P LSWC and now it's dead on.

[ImBroke]

Perhaps the rear u notch wasn't cut centered in the backstrap? I wouldn't worry about it until it comes back from S&W again. Hopefully they will fix it this time. Sounds like you went through the proper procedure to rule yourself out, good job.

[T2C]

It sounds like the barrel was screwed in too far, which will cause your pistol to shoot that far to the right. Contact S&W again and ask them to remedy the problem.

[SpankMonkey]

Have you tried 158's? Mine was consistently shooting low with 125 or 135's, but switched to Buffalo Bore 158 +P LSWC and now it's dead on.

This. You really need to try 158 grain rounds. I've had many j-frames that only 158 grain ammo would shoot POA/POI.

[CAVDOC]

Iirc the big dots are dovetailed into the barrel. If so just tap front sight in dovetail till you get zeroed

[The Dumb Gun Collector]

I think those big dots are actually pinned in. This is a factory only repair (or at least a gunsmith with balls and tools).

The only gun I ever had this issue with was a G17 years ago. Glock said I was limp wristing, holding my breath wrong, couldn't shoot, etc. I had a big-wheel Glock competition shooter and it shot even further to the left than with me (it seems I was already compensating). I hand carried it to Glock and the gunsmith took it to the range and confirmed it was bad. Then they shipped it back to me, with a target with a group about 1 inch to the left that said "Meets Glock Specs." I exploded and posted pictures on Glock Talk and Glock called me back just "asking to see how the gun was." The guy confirmed to me that they had someone who watched GT for these kinds of things. They gave me a new gun.

[HCM]

I'm a Firearms Instructor for my agency so I've learned the first thing to eliminate when diagnosing problems is "Loose nut behind the trigger":smile:

The 340 M&P has the newer style two piece barrel - The big dot is pinned with a roll pin.

Re bullet weight - changing bullet weight will affect POI with regard to elevation (high / low) but it doesn't affect windage in my experience. Regardless, the 135 grain +P gold dot is the only load I'm authorized to carry.

I'm thinking either the rear sight notch in the frame is off center or the barrel is "clocked" or screwed in to far but my understanding is that is not supposed to happen with two piece barrel. S&W addressed Barrel alignment last time it was there so ?????

Two of my co-workers have these and neither has windage issues. Nor does my 642 or my prior 640 BUG. It's just frustrating.

[turbo38gn]

Sounds pretty simple at this point, send it back, with a detailed lettter as you explained here and I would think it would be fixed.

[Failure2Stop]

The zero issue / hitting right is with the iron sights ( sorry if that was unclear in the original post.)

Sorry, jumped right to the laser as being the issue.
My bad.

[JGrelle]

I had the Exact same issue with my M&P 340, I sent it in to S&W last week, They received it on the 27th & it was finished & back on its way to me on Sat. the 2nd, Just picked it up this afternoon & it is good to go now, they aligned the barrel. Talk about fast service! I was expecting several weeks at the least, but it only took a few days, Way to go S&W!
They will get yours taken care of.


I’m having a zero issue with my S&W M&P 340. It’s the model with the factory XS Big Dot Front sight and Laser grips.

I purchased this weapon from a S&W Law Enforcement dealer with the intention of getting it approved for duty use as a back-up weapon to replace my S&W 642.

The M&P revolver functions and groups fine, however. at 7, 15 and 25 yards it consistently hits to the right / 3 o’clock. The group moves further to the right as the distance increases. Approximately 3” at 7 yards, 6 “ at 15 yards , 8-10” at 25 yards etc.

The first time I fired the 340 I used Remington lead free Frangible . I thought the zero issue might have been the lead free ammo so tried with our duty round, CCI/Speer 135 grain +P .38 special as well as Remington and Winchester standard velocity 130 grain FMJ .38 special.

To eliminate the possibility this was shooter error, I shot the same ammunition through my S&W 642. The groups were centered with all three types of ammunition. I then tried dry fire with the laser grips and saw no pronounced movement to the right. Finally I had another experienced shooter/ Firearms Instructor shoot the 340 – all rounds were to the right for the second shooter as well.

I contacted S&W customer Service, they sent me a fed ex label and the 340 went back to S&W. A few weeks later the 340 was returned. the work order read : “Customer Complaint – Barrel Frame Line-Up” and “ Repaired Adjust Barrel Alignment.”

I took the 340 out to the range last Friday and it is still hitting consistently to the right with CCI/Speer 135 grain +P . I again had a second experienced shooter fire the weapon and again all rounds were to the right for the second shooter as well as myself. The barrel / front sight appeared to be centered.

S&W is sending another Fed Ex label but any thoughts / suggestions on cause and possible solutions would be appreciated.

.

[Pappabear]

I took mine out a two weeks ago and shot the piss out of it. But I cant say I would know if it was hitting right a couple inches. Im happy to hit a steel plate at 25 yards. I was quick drawing but still, interesting.

Might take mine tomorrow and try some slooow fire and see.

That gun is awesome.

[JC1990]

I'll 2nd the using 158 grain bullets. My 640 Pro was aggravating with anything else. Buffalo Bore makes a good round in that weight. My M&P 360 was regulated for 158 grains as well

[HCM]

I'll 2nd the using 158 grain bullets. My 640 Pro was aggravating with anything else. Buffalo Bore makes a good round in that weight. My M&P 360 was regulated for 158 grains as well

My first back up gun, a 640, used to shoot POA/POI with 158 grain loads and Low with 110 grain +P+.

However, 158 grain is not an option anymore - I bought it as a back up gun for work - 135gr Gold Dot +P is the only authorized load for .38.

[HCM]

The 340 M&P came back from S&W two days ago. Got in a quick trip to the indoor range today - 30 rounds of 135gr +P GDHP at 7, 15, and 25 yards.

There is noticeable improvement but it is still hitting to the right . POI is about half as far to the right as before this trip to S&W.

Call me picky but this is not acceptable for a gun that costs nearly $800.

[spr1]

I would send it back and demand a new gun. I have successfully done that with lemons before.
Something is seriously misaligned.