The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > The Smithy

Reply
 
Thread Tools
Old February 7, 2012, 05:50 PM   #1
dajowi
Senior Member
 
Join Date: November 2, 2005
Posts: 976
Refit Barrel - STUMPED!

What are the main fixes to the problem of a firearm which fails to lock back on the last round fired from the magazine?

What benefit would refitting the barrel have in correcting this program?
dajowi is offline  
Old February 7, 2012, 05:54 PM   #2
jaguarxk120
Senior Member
 
Join Date: February 28, 2008
Location: Michigan
Posts: 1,944
It would be a great help if you told every one the Rifle involved.

Make, model, type of acton, caliber, size of magazine.

And why do you want to refit the barrel?
jaguarxk120 is offline  
Old February 7, 2012, 08:00 PM   #3
PetahW
Senior Member
 
Join Date: September 19, 2008
Posts: 4,679
[What are the main fixes to the problem of a firearm which fails to lock back on the last round fired from the magazine?]
Causes, not fixes:
A worn locking edge on a vertical magazine actuated slide lock.
A worn/broken stop latch.




[What benefit would refitting the barrel have in correcting this program? ] - None.

.
PetahW is offline  
Old February 7, 2012, 09:16 PM   #4
James K
Staff
 
Join Date: March 17, 1999
Posts: 19,482
The OP just said "firearm", which could include any gun with a magazine - pistol, rifle, or shotgun - including many that were never made to lock open on empty.

I think we need to wait for pictures or at least a better description of the "firearm."

Jim
__________________
Jim K
James K is offline  
Old February 7, 2012, 11:57 PM   #5
dajowi
Senior Member
 
Join Date: November 2, 2005
Posts: 976
The firearm in question is a Springfield Armory EMP 9mm 1911 pistol. It fails to lock back the slide on the last round fired. It makes no difference who shoots it. It malfunctions with both 115 Gr. and 124 Gr. FMJ ammo. It fails with all three magazines which came with the gun. The first trip back to SA the barrel was refitted and the slide stop was tuned. They machined off some of the back of the slide stop. The gun continued to malfunction. It went back to S.A. and is in the process of being returned. They again, refitted the barrel and did extensive test firing.

So beside the original question of what good would refitting the barrel do to correct this program? If it continues when returned are their other possible fixes?
dajowi is offline  
Old February 8, 2012, 04:19 AM   #6
gyvel
Senior Member
 
Join Date: August 30, 2009
Location: Northern AZ
Posts: 5,229
I can't think of any other reason besides magazine followers that aren't hitting the hold open, unless the barrel link is causing a slight downward twist of the slide stop. (I am assuming that there is a barrel link and not a cam lock arrangement.) The only other thing, although far fetched, is that the recoil spring is not allowing the slide to travel back far enough for the slide stop to engage.
gyvel is offline  
Old February 8, 2012, 12:32 PM   #7
brickeyee
Senior Member
 
Join Date: December 29, 2004
Posts: 3,342
Check if the magazine follower is catching the slide stop since that is how the 'last shot lock' operates.

See if the follower is catching when you hand cycle the slide (good test with dummy rounds).
Look down into the rejection port as you cycle the slide by hand.

If the mags have a lot of use on them they may need new springs.

You can also try different magazines.

If someone messed with the slide catch it may need to be replaced.
brickeyee is offline  
Old February 9, 2012, 06:27 AM   #8
HiBC
Senior Member
 
Join Date: November 13, 2006
Posts: 3,638
Maybe:Hotter ammo,firmer hold,lube,any rubber buffers added?.45 slide stop in a 9mm.

Q:Is it real easy to engage the slide stop manually?Smetimes a little detent is drilled in the slide stop,and it can be too much detent real easy.

Empty mag inserted,pull the slide full back,does it engage?

Weak mag spring?Try a new Wolfe +5%
HiBC is offline  
Old February 11, 2012, 02:50 PM   #9
dajowi
Senior Member
 
Join Date: November 2, 2005
Posts: 976
UPDATE: After a second trip to Springfield Armory for repair, (on their dime) the second "barrel refit" appears to have corrected the problem. Went to the range and shot 113 rounds of mixed 147 gr. fp, 115 gr. fmj and 115 gr. RNL. All worked perfectly with the exception that twice the slide failed to lock back on the 147 gr. FP. The OAL of the 147 Gr. cartridges are shorter than the other ammo I shot whether that had anything to do with it I don't know.
dajowi is offline  
Old February 13, 2012, 05:52 AM   #10
gyvel
Senior Member
 
Join Date: August 30, 2009
Location: Northern AZ
Posts: 5,229
A so-called "barrel refit" would make sense regarding my thoughts that the swinging link was exerting too much pressure on the slide stop.

The resulting friction/torsion when the barrel is swinging down out of engagement with the locking lugs in the slide would cause the slide stop to rotate down.
gyvel is offline  
Old February 22, 2012, 08:38 AM   #11
sarg1c
Junior Member
 
Join Date: February 19, 2012
Posts: 3
Refit Barrel-stumped

Check the lever spring, My Walther broke this very small spring and slide would not stay back on last round. I man. new spring, problem solved...
sarg1c is offline  
Old February 22, 2012, 08:53 AM   #12
ScottRiqui
Senior Member
 
Join Date: January 27, 2010
Location: Norfolk, VA
Posts: 2,905
I had the same problem with my brand-new EMP .40 S&W. Eight mags, and none would lock the slide back reliably. I contacted SA, and they sent me a new slide stop pin with a different profile (I think they called it an "A-cut profile") that fixed the problem immediately and completely.

Glad they got yours taken care of as well!
ScottRiqui is offline  
Old February 22, 2012, 08:53 AM   #13
Herr Walther
Senior Member
 
Join Date: April 10, 2001
Location: A Place Worse than California
Posts: 782
That little spring can get away from you too during a strip cleaning. I always have a few extra around.
__________________
"It was people who upheld their duties to their office, the constitution, and the public by opposing Hitler who were called traitors"
-------------------------------------
"...a historian asked what had happened to the German people for them to accept a criminal government. Unfortunately, nothing needed to happen. In nations across the world people accept government crime."
-------------------------------------
"In democracies as well as dictatorships, subordinates illegally obey their rulers. Subordinates who remain true to their oaths of office by opposing their rulers are rare."
Herr Walther is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 10:18 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.08670 seconds with 9 queries