M&P 9mm accuracy issue for me

[Bkreutz]

Obviously the rifling in the older models was causing a problem, otherwise S&W wouldn't have changed it.

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I have to disagree on this one. I think S&W changed the twist rate in response to perceived problems that were being discussed on various internet forums , Faster twist rates have some marginal improvements in certain situations but if it were a real problem, the barrel makers like KKM, Storm Lake and others would have changed to a faster twist rate, which they didn't All of my KKM barrels are a 1:18 (or so) twist rate which is what the older factory barrels are. I think changing the twist rate in the barrel was more of a marketing thing than an actual improvement in performance. (that way Smith could sell a whole new generation of M&P's to those that just have to have the latest version). I can swap barrels around to various manufacturers and twist rates and my accuracy is the same no matter which I am using. I did buy them to see if they were any better, and my male pride would sure like to say that I spent my money wisely, but IMO I didn't. Shooting better doesn't come from "upgrades" but rather from a lot of practice. "Upgrades" are fun, and I like new gadgets as much as the next "tinkerer". But in the end, it's boring practice that is the best return on investment.

 

[attrapereves]

I have to disagree on this one. I think S&W changed the twist rate in response to perceived problems that were being discussed on various internet forums , Faster twist rates have some marginal improvements in certain situations but if it were a real problem, the barrel makers like KKM, Storm Lake and others would have changed to a faster twist rate, which they didn't All of my KKM barrels are a 1:18 (or so) twist rate which is what the older factory barrels are. I think changing the twist rate in the barrel was more of a marketing thing than an actual improvement in performance. (that way Smith could sell a whole new generation of M&P's to those that just have to have the latest version). I can swap barrels around to various manufacturers and twist rates and my accuracy is the same no matter which I am using. I did buy them to see if they were any better, and my male pride would sure like to say that I spent my money wisely, but IMO I didn't. Shooting better doesn't come from "upgrades" but rather from a lot of practice. "Upgrades" are fun, and I like new gadgets as much as the next "tinkerer". But in the end, it's boring practice that is the best return on investment.

I messed with an aftermarket barrel for my Glock 20 and like you, found no improvement in accuracy. However, it's nice to be able to fire lead bullets.

Have you tried different bullet weights in your early stock barrel? Apparently the twist rate was causing issues with 115gr ammo, but other weights were fine. I usually shoot 124gr jacketed or lead and have seen no issues.

I read a few stories where people sent their guns to S&W and they suggested 147gr for whatever reason.

 

[Wessels69p]

I had some friends try it and have the same issues as I. I looked into the barrel change. Mine is a 2013 model and does not have the "improved" barrel update. I called S&W, they said due to people installing .40 barrels on 9's and vice versus, they won't sell barrels anymore (directly). He said I could send the gun in on a targeting warranty claim. Their spec is 3" group at 20ft. I do have an apex trigger so I'm sure I have to swap the stock one in before sending in.

 

[WR Moore]

OK, let's clear up the rifling twist issue. S&W used the 1-18.75 rifling twist on all their 9mm pistols from 1949 until very recently. There is no body of evidence suggesting that suddenly, the rifling twist presents an accuracy problem in need of solution. By recently changing rifling twist, S&W is simply changing to the rifling twist used most commonly for 9mm. The change may be of benefit to those competitors using 147 gr bullets at 800 fps or so.

Having disposed of that, we can move on. The trigger action of the M&P series is much like that of an extremely well tuned double action revolver. Many people more accustomed to the trigger action of most other semi-auto pistol designs tend to lose patience during the trigger stroke and finish it off with a hefty yank. This typically results in low, left hits for right handed shooters. Certainly did for me and for most of those I was instructing in transition training. This is corrected by practice, perhaps aided by qualified instruction.

So, hate to break it to you, but the problem is most likely software, the nut behind the trigger or however you wish to describe yourself. And any friends who may have "assisted" you.

Once you're accustomed to the trigger action, the sights may need a wee bit of adjustment to get the final shot placement correct.

 

[Johnmuratore]

Why should Smiths care about people using 9mm barrels in 40s? I'm sure they make money selling barrels, and if they don't they could raise the price. A company that doesn't want to sell something they could make money from needs help in the marketing/sales department.

 

[Wessels69p]

I do acknowledge that I may still be the problem. I'm going to the range and do some instructor assisted drills this Saturday before I buy a barrel or send back to S&W. Again, I am not bashing the gun. I love it and my other s&w pistol, too. I am just challenged with this particular one in ways I am not with my other handguns.

 

[Prasko]

Have someone else shoot it. It's a quick easy way to rule out user error.

 

[lhump1961]

Have someone else shoot it. It's a quick easy way to rule out user error.

...assuming the next person can shoot worth a....!

 

[Rastoff]

These accuracy issues are quite common with the M&P and the cause is almost always the shooter.

If you haven't shot the gun from a rest, any statement on accuracy is anecdotal. It is possible that there is a problem with the gun. It wouldn't be the first one. Still, the assessment cannot be made while shooting off hand.

 

[WR Moore]

Why should Smiths care about people using 9mm barrels in 40s?

One word: LIABILITY. If some lame, cheap individual chooses to misuse their product by using it in a manner never intended by the manufacturer and is injured, they-or their estate-will find a scum sucking shyster to sue S&W. The grounds will be that if the barrel wasn't intended to fit a .40 caliber slide, S&W should have made it impossible to be installed in that slide/pistol.

To those who decide to make multi-caliber pistols by sticking barrels into slides not intended for them: buy the conversion barrels made specifically for this purpose. It's still not a bright idea, but, hey, it's your life.

 

[Bkreutz]

Why should Smiths care about people using 9mm barrels in 40s? I'm sure they make money selling barrels, and if they don't they could raise the price. A company that doesn't want to sell something they could make money from needs help in the marketing/sales department.

Number of possible reasons

* Legal Liability (as already mentioned).
* Profitability, they would rather sell 2 complete pistols than 1 pistol and an extra barrel and mag.
* Distribution, if they can't keep up with demand from resellers (Midway, Brownells, etc who are in a constant state of "out of stock"), why would they care about selling barrels direct to the public?

Personally I lean toward reason #3, for a long time I thought it was #2, but as you said, selling a product is selling a product.

 

[ironhead7544]

If the groups are good but only low it is probably just the sights. Figure out how far low you are hitting and call S&W. They should have different sight heights available.

 

[Rastoff]

If the groups are good but only low it is probably just the sights. Figure out how far low you are hitting and call S&W. They should have different sight heights available.

No on all accounts. S&W does not offer sights of different heights for the M&P line.

Also, as long as you're doing everything the same, the groups will be good. I've seen guys jerk the trigger the same every time. They've put up some really small groups, but that only indicates repeatability not accuracy. The two are not inherently linked.

 

[Johnmuratore]

WR Moore
I have to give you props on that one.
I've never been called lame, cheap and not so bright all in one post.

 

[WR Moore]

De nada.

Nothing personal, but I've been involved with firearms for over 50 years and I'm continually amazed by the things people try to get away with. I've never had much of a yen to do multicaliber things, but a couple of extra bucks buys a barrel designed to accomplish that without any crossed fingers.

I've also had the opportunity to observe the results of a few 'neat ideas' that didn't quite work out as planned. No deaths or maiming, but I'm not real sure why in a couple of cases.

Just because it can (or looks like it can) be done, doesn't make it a good idea. Good Luck.

I'll also tell one on myself. I was once commisioned to build a muzzle brake for a .22 rf pistol. I studied brakes made by gunmakers and did some research and ciphering on design. When I did the prototype, I used the same method of attachment as a couple factory brakes. About the 5th shot I heard this strange sound.....which was the prototype rolling down the shooting lane. Apparently, my brake trapped much more gas than the factory brakes and the internal pressures were much higher. By the time the project was over I had a lot of respect for the pressures generated by the lowly .22rf

 

[chiro972b]

So far, I shoot my sig 2022 way better than my m&p pro 5". I did find if I slow way down and really, really concentrate, I can get good groups with the m&p but it's not nearly as effortless as the sig, but that just means I need more trigger time with the m&p.

 

[actionpistol]

I won a fs 9mm at a shoot which was was a custom from aiet. This already had the apex trigger trinium sights and slide serrations cut into top of slide. Anyway I played with it off the bench at 15 yds with multiple reloads. In bullet weights ranging from 115 to 147. This isn't my first 9mm. Groups at 15 yards ranged from 2 1\2 to 5 inches. Which I did not find acceptable. But I loved the feel of the gun. Bought the storm lake barrel improved groups by 1\2 inch. Won a bar sto barrel at shoot and ordered the match target and had it installed. Now shoots between 1 inch and 2 inches with pretty much all bullet weights. Friend of mine had fs with regular trigger I could put them pretty much in the same hole at 15 yds off the bench. Your results may vary but those were mine.

 

[rsrocket1]

With my M&P40 FS with either the 40 or 9 barrel (yes, i'm one of those guys) I use sight picture #3 at 10 yards. Unfortunately, with my SP2022 40 and all other pistols, sight picture #2 works best at 10 yards. I know the POI is higher at longer ranges because it is closer to sight picture #2 when I shoot clay pigeons on the 50 yard berm using a sandbag rest.