[jtucker]

I had been complaining about FTEs with my 9mm. I had been using WWB, several different boxes purchased at different locations. Today I tried some Remington UMC, 150 rounds (15 clips at 10 rnds each) with no FTEs. The only issue was twice the slide would not lock back after the last shot. Looks like my 9 doesn't care for WWB.

 

[Morphire]

Can you try taking a caliper to those WWB rounds and seeing what the overall cartridge length (OAL) is on them? I'm curious if overly long or short rounds are causing the FRB failures some have been experiencing with some 9mm factory rounds.

 

[G56]

Not all pistols or rifles like all ammo, that's why it's important to try ammo out, you found out yours didn't like WWB, that way you know what not to buy. In addition sometimes a pistol needs some break in, 1911's are notorious for that, but after you have shot a few hundred rounds out of it, you might try the WWB again to see if it will work.



If you haven't already cleaned and oiled it, you might try that also. I clean and lube all new firearms before shooting.

 

[greener]

Anyone found that ammo weight makes a difference with these problems?



I try to remember reports of problems with various brands of ammo. So far mine has fired around 2000 rounds of a mixture of the lowest cost I can find. About 1/3 has been WWB. I've had zero problems with any I've tried. The variations between pistols and ammo sure does make it interesting.

 

[G56]

So far all I have shot (40 S&W) is 155 gr and 165 gr, I haven't shot any 180 gr at all.

 

[jtucker]

I'll look to see if I have any of the WWB left. I may have the last of it in one of my Kahr mags. I actually own a set of dial calipers, so I can make an accurate measurement. BTW, I cleaned and lubed the M&P before the first range session and after each subsequent one, so I don't think that was the problem. I'd also like to note that mine still shoots consistently low. If I compensate for that I am geeting really good results as far as accuracy is concerned. I let the guy in the next lane shoot it also. I think we will have another member soon.



J. Tucker

 

[Arizona Smithshooter]

My M&P 9 had two FTE's early on, both with WWB ammo. In trying to figure out the problem I noticed a lot of carbon buildup underneath the extractor claw. Once cleaned, I shot various kinds of ammo without another failure. At least 1000 rounds of WWB have since been shot through the gun without another failure. Now I pay close attention to the extractor when cleaning.

 

[G56]

I'd also like to note that mine still shoots consistently low.

J. Tucker

Shooting low with what weight bullet? Generally speaking lighter bullets will impact lower on the target than heavier bullets, so if it's shooting low with 155 or 165 gr bullets, switching to 180 gr might make the difference.

 

[greener]

My M&P9 shot consistently low (4-6"). I tried bullet weight and shooter retraining to no avail. Shipped it to S&W and it came back with a shorter front sight. Today it pretty much shot POA at 25 yards with 115 gr and 147 gr. Couldn't tell much difference between the two weights.



As a last resort, blame the pistol. Worked in my case.

 

[tstrenuous10]

my M&P .40 didn't always lock the slide back when I ran out of ammo using WWB for a day but a different day it was completly fine.

 

[revolverman357]

My M&P9 does not like WWB at all. Rem umc for now on, or handloads work great.

 

[jtucker]

9mm dimensions

By request, here are the average dimmensions of the Remmington and WWB:

Avg Length: WWB = 1.157" Rem = 1.106"

Avg Dia: WWB = .386" Rem = .386"

The diameter was measured at the rim.

 

[UPSguy]

Re: 9mm dimensions

By request, here are the average dimmensions of the Remmington and WWB:

Avg Length: WWB = 1.157" Rem = 1.106"

Avg Dia: WWB = .386" Rem = .386"

The diameter was measured at the rim.

by any chance did you measure the case lengths? Were these both 115grs?

 

[Morphire]

Thank you for the time with a calipers. I'm finding my M&P9 Standard likes shorter loads if I'm using JHP. So far the load it likes appears to be between 1.130" and 1.140" with Zero 115 JHP bullets.

 

[ClosetCaseNerd]

Okay I mentioned this in another thread but, does nobody else think that because the MP9 uses the same mainspring as the MP40 that it may have a detriment to ejection and feed reliability? I test shot an MP9 and it dribbled brass across my forearm. My MP40 (and the other I tested before I bought it) flings brass a few feet with authority. Both pistols firing Rem UMC. Granted this is an extremely small sample and shouldn't be taken as reliable findings, but in theory I could see to strong of a spring being a factor in extraction/feeding reliability.



Could be coincidental, but anyone with more time with a few of each variant (possibly the smiths on this board...) and have any observations that could confirm/mitigate my hypothesising?

 

[UPSguy]

I am not a smith but this has being brought up numerous times already. The gun is not having a problem ejecting it is having a problem extracting WWB. Since it will extract just pulling the slide back slowly while doing a press check I "think?" that eliminates the same spring as being the culprit here.

 

[ClosetCaseNerd]

Since it will extract just pulling the slide back slowly while doing a press check I "think?" that eliminates the same spring as being the culprit here.

If anything, the point that the extractor is gripping the rim fine during hand cyclnig would make me look closer at springs being too strong for reliable ejection in light recoiling target ammo.

 

[UPSguy]

I don't think anyone is having failures to eject, they are having failures to extract. Hence my opinion that this is not recoil spring related.