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I love the M&Ps.. but I'm losing faith.

3187 Views 19 Replies 9 Participants Last post by  lugnut
I've been having feeding problems with my FS .40. The round jams on the ramp with the bullets usually at least partially in the chamber. I know I've had my mag slip out before but I think this is different.... plus I've replaced the mag release with a new one yesterday. However today after shooting about 150 rounds I had this problem 4 times- (rounds in the middle of the magazine)!! When the problem occured the rounds chambered with a tap of the bottom of the magazine. This is addition to the small slivers of plastic that chipped off of my frame where the slide dust cover stops... S&W said this was not an issue. I'm going to replace the recoil spring and see if things get better. I love the guns but this has cost me time in matches and frustration in practice.



My M&P 9mm is a good shooter but I have the problem with occational brass spitting in my face.



I only use these guns for competition and when they are running right they are great... but I'm getting impatient. I'm hesistant to send it to S&W as it has a great trigger job on it... and since I'm from MA I don't want S&W to replace it with a crappy 10lber!



Sorry... I don't mean to vent and complain as I do love S&W... but I'm frustrated now.
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Hope everything turns out....
choochboost said:
How many rounds through it so far?


Just at 3400 now.
Sorry to hear. Send it in without trigger parts, or put factory stuff back in.
Well there's no doubt its broken in. I'm sure that's an easy fix for S&W.
So someone modified your pistol ("great trigger job") and now it's not working. Did it have any of these problems before the "great trigger job" by chance? Did this "great trigger job" happen to involve polishing the feed ramp or any work to the chamber?



When you replaced the mag catch, did you use a factory standard part? There are folks on this forum who recommend doing a little "work" removing material from the catch. Done improperly, this could easily result in a magazine that isn't being held in place properly therefore resulting in misfeeds.
ToddG said:
So someone modified your pistol ("great trigger job") and now it's not working. Did it have any of these problems before the "great trigger job" by chance? Did this "great trigger job" happen to involve polishing the feed ramp or any work to the chamber?



When you replaced the mag catch, did you use a factory standard part? There are folks on this forum who recommend doing a little "work" removing material from the catch. Done improperly, this could easily result in a magazine that isn't being held in place properly therefore resulting in misfeeds.


Only work was on the sear and the trigger bar. The trigger work was done months and about 3000 rounds ago. Nothing on the barrel/chamber at all. Nothing on the mag catch.
So your gun ran fine for 3,000 rounds and suddenly it's having a problem feeding?



More basic questions, nothing against you personally just a standard approach:



1. Have you been cleaning and lubricating the gun the same way as always? Same solvent, same lube, same method, etc.



2. Is it happening with all ammunition or just one particular load? If just one, have you shot that ammo successfully in the past?



3. Is it happening with all your mags or just one mag?



4. You said you replaced the mag catch. Did the problem only begin after you put the new mag catch in?



In my experience, guns don't spontaneously start having feeding problems like this. If the gun was new, maybe there could be a defect. If the gun was nearing the end of its service life, maybe something has worn out. But at 3,400 rounds you'd expect the gun to be just fine. So unless something has changed recently (like the mag catch) it's an awfully odd problem.
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ToddG said:
So your gun ran fine for 3,000 rounds and suddenly it's having a problem feeding?



More basic questions, nothing against you personally just a standard approach:



1. Have you been cleaning and lubricating the gun the same way as always? Same solvent, same lube, same method, etc.



2. Is it happening with all ammunition or just one particular load? If just one, have you shot that ammo successfully in the past?



3. Is it happening with all your mags or just one mag?



4. You said you replaced the mag catch. Did the problem only begin after you put the new mag catch in?



In my experience, guns don't spontaneously start having feeding problems like this. If the gun was new, maybe there could be a defect. If the gun was nearing the end of its service life, maybe something has worn out. But at 3,400 rounds you'd expect the gun to be just fine. So unless something has changed recently (like the mag catch) it's an awfully odd problem.


1) Yes

2) All ammo, which I've used in the past.

3) I haven't isolated the mags yet... close inspection looks like there are no problems. I will be marking them going forward.

4) Problem occured before and after replacing mag catch.



This problem started to appear at about 2800 rounds. Seems to be occuring more lately for sure.
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Try and figure out if it's just one mag. Otherwise, the only advice I can offer is to send the gun back to Smith, then. Very odd to have something like this start out of nowhere.
Just out of curiousity, what are you shooting through it?



Only thing my fullsize .40 doesn't like so far are montana gold 155gr hollowpoints. Those things are so cone shaped, that it just guides the feed ramp to the case rim. They might work with a roll gripm, but I avoid roll crimps in anything that isn't beign fed to a revolver.
Could it be a weak recoil spring that has lost just enough oomph that it sometimes fails to pull the slide fully back into battery after so many rounds?
Mag problem

Sounds like a mag problem. Most FTF are due to bad mags. Also, check at the base of your magwell and make sure nothing is keeping your mag from setting correctly. Also check inside the mag well for something causing the mag to set at an odd angle etc.



When all else fails and I can not find a what is causing me problems. I take everything apart and scrub and scurb and scurb. I follow that up with a good polish. I would also clean my magazines.



Good luck
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Thanks for all the good ideas guys. I'll change the recoil spring and mark suspect mags.



The bullets I'm using mostly are Berrys 180gr and WWB 165/180gr bullets. I guess it is possible that the funny shape of the Berrys and WWB 165gr (bullets are more staight on the sides as opposed to the rounded CCI 180grs). What I don't understand how it's become more of a problem recently. I'll try shooting other bullets to see what happens as well.
This might help a bit. I have been loading 155gr Rainier flat points (they're cheap) since late last year. During my load work-ups, I found that my flat-point loads over 1.130" OAL were prone to jamming against the top of the chamberI reduced them to 1.125" and all traces of it stopped. I load a meduim load of CLays, so my energy levels aren't real high, but I have reliable cycle as long as the OAL is below 1.130". Usually, all it takes is a slight pull back on the slide for the round to free up and go about it's business of being potential energy. I think it's your bullets. I've shot 165gr WWB with no issues, but that ammo has had QC issues before. IF those rounds were slightly long, they might jam like that, simply because the 165's are a tapered down 180gr, very similar to the Berrys.



The kicker is the Mag fix. All of the M&P's have somewhat loose tolerances at the mag-well. Mine usualy has a little bit that I can force it up further into the well. When you jam up in the chamber like that, and you push the mag in further, you're reducing the angle of the bullet to the chamber, and it frees up.

Try a lower charge and shorter OAL with the berrys, or a different profile bullet. I'd put 10 on that being the problem. If you're convinced it's an actual wear problem with the gun, a RN 165, shouldn't work. Run 100 CCI Blazer Brass 180's through it. If it jams in that same fashion, I will send you my $10.
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FieroCDSP said:
This might help a bit. I have been loading 155gr Rainier flat points (they're cheap) since late last year. During my load work-ups, I found that my flat-point loads over 1.130" OAL were prone to jamming against the top of the chamberI reduced them to 1.125" and all traces of it stopped. I load a meduim load of CLays, so my energy levels aren't real high, but I have reliable cycle as long as the OAL is below 1.130". Usually, all it takes is a slight pull back on the slide for the round to free up and go about it's business of being potential energy. I think it's your bullets. I've shot 165gr WWB with no issues, but that ammo has had QC issues before. IF those rounds were slightly long, they might jam like that, simply because the 165's are a tapered down 180gr, very similar to the Berrys.



The kicker is the Mag fix. All of the M&P's have somewhat loose tolerances at the mag-well. Mine usualy has a little bit that I can force it up further into the well. When you jam up in the chamber like that, and you push the mag in further, you're reducing the angle of the bullet to the chamber, and it frees up.

Try a lower charge and shorter OAL with the berrys, or a different profile bullet. I'd put 10 on that being the problem. If you're convinced it's an actual wear problem with the gun, a RN 165, shouldn't work.
Fiero- those are some good ideas. I actually usually load the 180gr Berrys to 1.125" COL but I know some have got close to 1.30". I use 6.2gr of Power Pistol for a relatively mild load. The more I look at those bullets the more I wonder about that being part of the issue. I do have several boxes of the CCI 180grainers so I might just use all them to see if the problem persists. I will say that I don't honestly recall this problem with the WWB 165gr bullets but either way you might be onto something. It's just wierd that it seems to be happening more lately.
On another note... does anyone know if the shape of the Rainier bullets are the same as the Berrys or do they have a rounded shoulder? I'm talking about the 180gr .40 S&W obviously. Thanks



EDIT: I think the Rainier RNFP are what I would want as opposed to the regular FP.
Just made a batch with 1.123" +/- .002 COL with just a tad more crimp for good measure. Let's see how things work out.
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