Smith & Wesson Forum

Go Back   Smith & Wesson Forum > Smith & Wesson Semi-Automatic Pistols > Smith & Wesson M&P Pistols
o

Notices

Smith & Wesson M&P Pistols All Variants of the Smith & Wesson M&P Auto Pistols


Reply
 
Thread Tools Display Modes
  #1  
Old 11-21-2011, 11:55 PM
HunterL35 HunterL35 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Sep 2011
Location: Grand Rapids, MI
Posts: 13
Likes: 0
Liked 0 Times in 0 Posts
Default Why won't my M&P 45 slide lock back after last shot?

After shooting about 200 rounds of winchester white box this past weekend my slide only locked back after firing the last round about 4 of the 20 magazines that I shot ? Not sure what's going on?

Anyone have similar experiences or know what's going on?

Last edited by HunterL35; 11-22-2011 at 12:00 AM.
Reply With Quote
  #2  
Old 11-22-2011, 12:19 AM
OKFC05 OKFC05 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Aug 2007
Location: Oklahoma
Posts: 8,158
Likes: 3,605
Liked 5,199 Times in 2,172 Posts
Default

Not enough info.
Was the gun cleaned and lubed per manual before firing?
Have the magazines been disassembled, cleaned and wiped dry?
Is it only one magazine acting up, or multiple?
Is this the first time you fired the gun?

The reason I ask is the large number of people who shoot a new gun without cleaning it first and get problems at the range.
__________________
Science plus Art
Reply With Quote
  #3  
Old 11-22-2011, 12:37 AM
HunterL35 HunterL35 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Sep 2011
Location: Grand Rapids, MI
Posts: 13
Likes: 0
Liked 0 Times in 0 Posts
Default

I have shot 616 rounds exactly out of my pistol and have cleaned it throughly after every outing which usually consists of 100-150 rounds on average. I have a total of 3 magazines and have not been keeping track of whether any of them do it more than others but I load all 3, shoot them all, load them all again, shoot them, and so on... I have never disassembled the magazines but wipe them down and clean the inside with a rag and a brush.
Reply With Quote
  #4  
Old 11-22-2011, 12:49 AM
Dragon88 Dragon88 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Dec 2009
Location: North Carolina
Posts: 3,054
Likes: 107
Liked 456 Times in 205 Posts
Default

Put an empty magazine in the unloaded gun and rack the slide. Does it lock back? Please try this at least five times with each of your magazines and report back.
Reply With Quote
  #5  
Old 11-22-2011, 12:50 AM
OKFC05 OKFC05 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Aug 2007
Location: Oklahoma
Posts: 8,158
Likes: 3,605
Liked 5,199 Times in 2,172 Posts
Default

Suggest you number your magazines and note any failures by specific magazine.
Suggest you disassemble and clean your mags when new before shooting, and at least every 1000 rounds or so. I spray all the parts with CRC Silicone, wipe dry and reassemble. No wet lube in mags.
Combination of dirty mags and wimp ammo can cause failure to lock back. Also grit in slide lock on gun, or excessive lubrication.
After all those possibilities are eliminated, the next likely candidate is one bad mag, followed by damaged slide lock.
Do 88's test above to check for mechanical problem.
__________________
Science plus Art
Reply With Quote
The Following User Likes This Post:
  #6  
Old 11-22-2011, 11:21 AM
Armed Babysitter's Avatar
Armed Babysitter Armed Babysitter is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Oct 2011
Posts: 182
Likes: 21
Liked 31 Times in 23 Posts
Default

Could be a mag problem, might not be. I've seen guys have that problem because their thumb rides the slide release during recoil.

Insert empty mags and see if the slide locks back, and go from there. Hope you get it solved without a trip back to MA.
Reply With Quote
  #7  
Old 11-22-2011, 11:24 AM
10 X 10 X is offline
Member
 
Join Date: May 2008
Posts: 129
Likes: 0
Liked 4 Times in 4 Posts
Default

Simple answer:
If you can manually pull back the slide with the mag in and the slide locks back and won't lock back when firing, then when firing the slide is out running the mag spring. You need to get stiffer (+5% or +10%) mag springs from someone like Wolff Gunsprings.
Reply With Quote
  #8  
Old 11-22-2011, 11:28 AM
evnash's Avatar
evnash evnash is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Dec 2009
Posts: 395
Likes: 0
Liked 144 Times in 51 Posts
Default

dirty mags.
Reply With Quote
  #9  
Old 11-22-2011, 02:15 PM
weum817 weum817 is offline
Member
 
Join Date: Dec 2007
Location: Carlisle, KY
Posts: 20
Likes: 0
Liked 1 Time in 1 Post
Default M&P

I work for an agency that just went from M&P to glock.. We had this happen all the time..with the ambi slide release lever ...most of the time the person accidently is either touching the slide stop lever...( you barely have to touch it on either side) or a mag problem.. we also had several slide stops wear just a little (even on new guns)
this was an ongoing problem..
Mine did it a lot and I have fired several thousand rounds through it and kept it well cleaned, it's just a problem some of them have.
Reply With Quote
  #10  
Old 11-22-2011, 04:02 PM
handgunner356 handgunner356 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Dec 2003
Location: SE Iowa on the Mississipp
Posts: 3,137
Likes: 1
Liked 352 Times in 230 Posts
Default

All things mentioned can cause the problem, I would be inclinded to think the Winchester White box might not be that hot. Not cycling the slide far enough to the rear long enough for the stop to engage. Add a dry gun, loose grip, thumb riding or dirty mag and it becomes that much more likely. If the slide locks back every time manually then ammo would be my first change.
Reply With Quote
  #11  
Old 11-22-2011, 06:06 PM
Hammerdown77 Hammerdown77 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Jul 2010
Location: North Alabama
Posts: 228
Likes: 0
Liked 28 Times in 15 Posts
Default

Winchester White Box is plenty hot. 850 fps over the chrono out of several of my guns. I've run 700 fps handloads that cycle the slide fine.

My slide won't lock back if the thumb of my trigger finger hand (strong hand) bumps the slide release under recoil. I shoot thumbs forward, strong hand thumb resting on top of the base of the support hand thumb.

Try locking back the slide with the empty mag like previous posters suggested. If that works, try making sure you have none of your fingers/hand near the slide release. if you shoot thumbs forward, try tucking the strong hand's thumb under the other hand, just as an experiment.
Reply With Quote
  #12  
Old 11-23-2011, 06:58 AM
Bicky Robby's Avatar
Bicky Robby Bicky Robby is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Jun 2011
Location: Smack dab in the middle
Posts: 304
Likes: 0
Liked 7 Times in 5 Posts
Default

Thumb to high on the frame is making contact with the slide release. I fight this all the time myself. Try adjusting grip and dry fire in a safe direction in your home.
__________________
NRA Certified Instructor
Reply With Quote
  #13  
Old 11-24-2011, 06:08 AM
Martya's Avatar
Martya Martya is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Dec 2010
Location: NW PA
Posts: 897
Likes: 343
Liked 446 Times in 240 Posts
Default

On my M&P45FS when the the slide lock engages the slide the tab goes up barely 1/3 of the way into the notch in the slide when the mag is empty. I have not done it yet, and I might the next trip to the range, but I can imagine slamming a loaded mag in there with enough exuberance that the slide jumps the lock tab and chambers a round. I believe I have read posts about that happening.

When I manually engage the slide lock the little tab fully engages the slide notch.

Could a bit of grit in just the right spot further hinder the slide lock from properly and fully 'rising to the occasion'?
__________________
Marty 4513TSW 13-1 642 60-10
Reply With Quote
  #14  
Old 11-30-2011, 09:39 PM
RJR573 RJR573 is offline
Member
Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot? Why won't my M&P 45 slide lock back after last shot?  
Join Date: Aug 2010
Location: Springfield, Missouri
Posts: 47
Likes: 1
Liked 3 Times in 2 Posts
Default

How well does the tab on the slide release contact the mag follower ?

On my M&P9 and others I've seen the metal tab does not contact the follower very well and may slip off or just not get pushed up with enough force to get all the way into the notch in the slide. If you bend the tab down slightly it will get a little more bite on the follower.
Reply With Quote
Reply

Tags
glock, lock, winchester

Thread Tools
Display Modes

Posting Rules
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Last round shot and slide locked back armallard Smith & Wesson M&P Pistols 14 05-09-2016 05:44 PM
Another M&P BG 380 slide failing to lock back brianjmac Smith & Wesson M&P Pistols 6 01-09-2016 12:56 PM
lock back slide dugsok Smith & Wesson M&P Pistols 6 12-16-2014 09:53 AM
Mod 41 will not lock slide on last shot dobe Smith & Wesson Semi-Auto Pistols 9 09-04-2010 06:17 PM
mdl 952 slide does not lock back after last round Peakbagr Smith & Wesson Semi-Auto Pistols 8 03-28-2009 01:16 PM

Powered by vBadvanced CMPS v3.2.3
smith-wessonforum.com tested by Norton Internet Security smith-wessonforum.com tested by McAfee Internet Security

All times are GMT -4. The time now is 02:22 PM.


Smith-WessonForum.com is not affiliated with Smith & Wesson Holding Corporation (NASDAQ Global Select: SWHC)