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Why won't my slide lock back after last shot fired?

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July 18, 2010, 09:41 PM
ajp3jeh
Why won't my slide lock back after last shot fired?
On other weapon systems, like the magazine tube spring on an 870 or the buffer spring on an AR, there is a certain maximum and minimum length for springs. Has anyone tried to come up with numbers for Sig pistols?

I had a P220ST that wasn't reliably locking back. When I checked the magazine springs, the worst culptrits had springs that were roughly 6 1/2" long. Springs that were 6 3/4" locked back most of the time. This compares to the length of the new factory spring of 8 3/8".

FWIW, the magazines are 8 rounder current spec with the dimple.

When it comes to troubleshooting this issue, I found the best indicator was how deeply the slide catch lever engaged the notch in the slide. On the weaker springs, it was not at the top of the notch while the new springs drove it to the top.


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July 26, 2010, 03:56 AM
ybrik
On my first day in the range with my bnew sig p226 navy, I noticed the slide won't lock back after every last round. Just kept on shooting and thought this is a break-in period.
I let my wife shoot it and was surprised the slide locked on her last shots.
On our way home, I began to think that I may have not gripped the pistol firmly during shooting.
...In the end, I realized my thumb is pressing down the slide release everytime I shoot.
This is the way I shoot on 1911 pistols. Thumb pressing down on thumb safety lever.
November 27, 2010, 10:35 PM
the sparky
I have the same problem with my clips with respect to the ability to load ammo. can't get more than 3-4 to load and they have to be forced.


December 01, 2010, 09:39 PM
Flyinfast
Very helpful post.




May The Road Rise With You.

January 26, 2011, 02:44 PM
dhjenkins
I would add one more thing to the list, though it's probably not that large a concern in the civilian community:

Operator inteference with the slide's rearward movement.

Example - a shooter is employing a close in combat grip while firing. Unfortunately, his slide is hitting his gear/vest and not allowing the weapon to cycle back fully. Obviously this could cause other problems as well, but there's a sweet spot for everything and the slides don't "push back" as hard as you think.

In fact, you can grip the slide & frame together in front of the trigger guard and fire the weapon without damage to your hand.

This is something to remember if you're deep in it and your weapon has been taken from you. Grab that S.O.B. and do NOT let go. It'll fire once, but only once, giving you a chance to hit your assailant with whatever else you've got on you.


------------------------------------------------------------
Sig Sauer Factory Certified Armorer
March 25, 2011, 08:56 PM
cyberphobia
New SIG 226 .40, slide will lock back with all but 12 rounds in the mag.
0 to 11 it locks but that 12th round never.
Only put 150 down the pipe.
Most frustrating.


"Advertising is the art of convincing people to spend money they don't have for something they don't need"

Will Rogers

SIG 229R LEGION SAO
SIG 226R Elite SAO
COONAN COMPACT .357 MAG



March 31, 2011, 07:26 PM
Love Da Sig
quote:
Originally posted by cyberphobia:
New SIG 226 .40, slide will lock back with all but 12 rounds in the mag.
0 to 11 it locks but that 12th round never.
Only put 150 down the pipe.
Most frustrating.


Cyber - I had the same issue with my new P226 in 9mm awhile back. It wasn't the gun, it was the springs in the mags - even though they were all either new Sig factory or Mec-gar.

Bought a six pack of Wolff Gunsprings 10% extra power mag springs, 100% lockback unless the ID10-T behind the grip rides the slide lock....

Grab yourself a six pack of the above and you should be good to go. Surely can't hurt to try.


NRA Endowment Member
April 15, 2011, 03:45 AM
nvision
sigh, i guess this issue persists up to this day. i live in CA and got my new p226 9mm last week, and just went to the range tonight to break it in for the first time. the slide would not lock open after the last round, and would not manually lock with an empty magazine inside.

here's the odd thing: with the empty magazine inserted, the slide would not lock manually as i've mentioned. HOWEVER, when i experimentally engage the slide takedown lever (by turning it downward) the slide DOES lock manually with an empty mag inside.

so after reading 9 pages of this thread past 1am in the morning, which part is really the issue - mismatched slide catch lever, bad slide catch lever spring, mismatched 10rd magazine followers, or poorly calibrated slide takedown lever? Wink

think a call to Sig is in order.
April 15, 2011, 07:11 AM
cyberphobia
My mate has a 226 so I used his mags in my gun and my mags in his gun.
His mags did the same in my gun did not lock after last round but my mags worked perfectly in his ergo not the mag springs!!.

I noticed the part number for the slide catch and the spring are the same for the 229,
SO I have swapped out the side catch and spring from my CPO 229 and the 226.

I will be going to the range a week today to see what happens with the two pistols.
See if the problem transfers across.


Watch this space.
Smile


"Advertising is the art of convincing people to spend money they don't have for something they don't need"

Will Rogers

SIG 229R LEGION SAO
SIG 226R Elite SAO
COONAN COMPACT .357 MAG



May 01, 2011, 10:08 AM
ffhounddog
I had issues with my P226 equinox in 40 yesterday. 3 mec gar and 3 factory and they did not lock back. Only shot 430 rounds of 180 grain stuff. The mec gars are 15 rounders and the factory are 12 rounders.

Should I get a new slide catch spring or new recoil spring or mag springs for the mags?

Ffh
May 01, 2011, 11:42 AM
gearhounds
Could also be a case of excessive lubrication, I suppose. I have seen it occur, especially with various grease lubes, and also with way too much oil. That seems like a really low round count to be a spring problem, unless they all came from a bad tempering, which the chance of would be astronomical.




“Remember to get vaccinated or a vaccinated person might get sick from a virus they got vaccinated against because you’re not vaccinated.” - author unknown
May 02, 2011, 09:03 AM
ffhounddog
I will take off the TW-25 and use slip2000 and see if that works.
May 14, 2011, 04:40 PM
fastk9dad
Had an interesting experience with my 220CED the past two range outings with it failing to lock back. At first I though it was magazine related as it only seemed to do it with two particular magazines (my two carry mags that are always loaded), then I noticed it would only do it on those magazines with a particular ammo (Winchester Ranger T 230gr I had just picked up for carry). I had previously been shooting PDX1, Win-Clean and Lawman with no issues. That was last Sunday and I only brought 50 rounds of the Ranger with me so I couldn't diagnose any further.

I went back today with 100 rounds of Ranger and some Magtech range ammo. With the Ranger it would still fail to lock back sometimes and this time it would fail with any of my 4 magazines. I was only loading a couple of rounds and making sure I wasn't accidentally hitting the release - which I wasn't. Through trial and error I discovered that if I held it with a stronger than normal grip the Ranger ammo it would lock back every time. And it's not like I have a loose grip or was limp wristing it in the first place. I then tried some of the Magtech and purposely limp wristed and it would lock back every time - I couldn't induce a failure.

Not sure why only the Ranger T gives me this issue. I might try replacing the slide release spring as it is a little stiff compared to my 228R. Gun now has 523 rounds through it so it's still fairly new and I grease the rails with Weapon Shield.
May 14, 2011, 05:41 PM
gtwnsig
quote:
Originally posted by fastk9dad:
Had an interesting experience with my 220CED the past two range outings with it failing to lock back. At first I though it was magazine related as it only seemed to do it with two particular magazines (my two carry mags that are always loaded), then I noticed it would only do it on those magazines with a particular ammo (Winchester Ranger T 230gr I had just picked up for carry). I had previously been shooting PDX1, Win-Clean and Lawman with no issues. That was last Sunday and I only brought 50 rounds of the Ranger with me so I couldn't diagnose any further.

I went back today with 100 rounds of Ranger and some Magtech range ammo. With the Ranger it would still fail to lock back sometimes and this time it would fail with any of my 4 magazines. I was only loading a couple of rounds and making sure I wasn't accidentally hitting the release - which I wasn't. Through trial and error I discovered that if I held it with a stronger than normal grip the Ranger ammo it would lock back every time. And it's not like I have a loose grip or was limp wristing it in the first place. I then tried some of the Magtech and purposely limp wristed and it would lock back every time - I couldn't induce a failure.

Not sure why only the Ranger T gives me this issue. I might try replacing the slide release spring as it is a little stiff compared to my 228R. Gun now has 523 rounds through it so it's still fairly new and I grease the rails with Weapon Shield.


I've been having a similar issue too. Mine fails to lock back with federal red box and WWB in both 165 & 180 gr. Not all of the time, but more times than not. Don't have a problem with Speer Lawman in 165gr.

I've gone throught the check lists at the top of the post and I'm wondering now if its the grease I'm using (Shooter's Choice). I'm going to clean it well before my next outing and just use oil to see if that resolves the issue.


________________________
The collection is growing

P226R Elite Dark
STI Edge
May 20, 2011, 10:28 AM
cyberphobia
I compared the inards on my 226 and 229 and noticed the safety lever was sticking up on the 226 and was down on the 229, the safety lever is binding on the sear or frame on the 226.

Also when I take the slide off the 226 it seems to get stuck just about where it contacts the saftety lever.
Same when I put the slide back on with the hammer cocked it gets stuck at the safety lever;
with the hammer decocked the slide goes on much easier.
I am thinking the slide is hanging up on safety lever and causing the last shot problem.
Any thoughts on this.

Today I am shooting with my mate who has a 226 I am going to swap slides and frames to see if this happens on his 226.
Watch this space


"Advertising is the art of convincing people to spend money they don't have for something they don't need"

Will Rogers

SIG 229R LEGION SAO
SIG 226R Elite SAO
COONAN COMPACT .357 MAG



May 29, 2011, 07:20 PM
Section88
I have also seen 2-3 new Sig 226's and 1 220 in the last 6 months that had slide release levers that were to thick and were binding very badly on the mags. With the slide removed the lever was binding so bad there was no way the mag spring could raise the lever. I had to use a dremel with a sanding drum and take a little material off at the lower rear corner of the release on the inside, I just took a little off until the lever would move as it should with a mag in and the slide off.
May 30, 2011, 11:05 AM
gtwnsig
quote:
Originally posted by gtwnsig:
I've been having a similar issue too. Mine fails to lock back with federal red box and WWB in both 165 & 180 gr. Not all of the time, but more times than not. Don't have a problem with Speer Lawman in 165gr.

I've gone throught the check lists at the top of the post and I'm wondering now if its the grease I'm using (Shooter's Choice). I'm going to clean it well before my next outing and just use oil to see if that resolves the issue.


UPDATE: Well I tried two things, one I angled the top of my magazine springs up a tad and then removed the Shooter's Choice grease and used the TW-25 sample that came with my 226. Worked great had no problems with Federal red box 180 gr. anymore. However, the Fed ammo wasn't as accurate as the Speer Lawman, so I'm back to the grease. It was more of an excerise to insure the gun worked with whatever I put through it and just a matter of principle.


________________________
The collection is growing

P226R Elite Dark
STI Edge
September 11, 2011, 08:01 AM
Sig Marine
While uncommon, failing to slide lock with newer guns can sometimes be attributed to the slide catch lever.

It's possible there's a burr on the lever which doesn't allow it to lift smoothly. You can check this by removing the slide and manually lifting the lever to see if it operates without hang-ups. If it moves freely, take a look at the magazine follower tab on the slide catch lever. This is the part of the catch lever that contacts the magazine follower to lift it into the slide arresting notch.

When I had issues with a P226, I discovered that Sig had two versions of slide catch levers. One designed for low capacity magazines (10 round) and another for hi-cap mags. If you are using 10 round magazines with a hi-cap slide catch, the magazine follower will not provide enough lift to engage the lever fully in the slide arresting notch.

Below is a picture to show the difference between the slide catch levers. The one on the left is capable of low capacity and high capacity magazines. The lever on the right, notice the notch on the magazine follower tab, will only work with high capacity mags.



Hope this helps...Semper Fi


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September 26, 2011, 06:29 PM
Harkonen
Hey guys, I'm having this problem on my W. German P228 that I picked up a few weeks ago. It's in mint LNIB condition, the previous owner only put about 20 rounds through it. I made sure my grip wasn't depressing the slide lock and with both factory magazines two different 115gr varities failed to lock back. I then field stripped the gun after I got home and noticed the rails were bone dry! Thankfully the recoil spring was on correctly and the gun itself was clean but there was no lubrication anywhere.

I went ahead and cleaned/lubed everything, ordered a Mec-Gar mag and am waiting for it to arrive to do another test. One question - when testing the last round to see if the slide will lock will it be ok to just load up one round in each magazine? Also, I think I assembled my magazines properly - how would one tell if the spring orientation is correct?
November 04, 2011, 12:19 AM
Will938
Thanks for the write up, I was having this same problem.