Intermittent partial slide lock

[ziebart]

It seems to be getting worse, but I am having intermittent issues where the slide will stick partially back (about every 100 rounds or less). The slide stop is not engaged. The magazine will drop free. You cannot rack the slide with normal force. To unstick the slide I have to give it a hard rap forward. Once that is done most times it will move freely. Sometimes it will go forward, but still require excessive force to cycle.

 

It has been back to the smith and they replaced the recoil spring saying that it was most likely coil bind and a bad spring. This is due to the fact that they were able to duplicate the issue prior to changing the spring, but not after. 1 magazine was shot after replacement of recoil spring. 

 

Smith assures me that nothing is wrong with the lugs. My buddy has concerns since it looks like the metal is rolling over and people have noticed tumbling bullets in targets during matches I've shot. Buddy thinks the gun is now unlocking too early causing baffle strikes.

 

Anyone have any thoughts?

[GringoBandito]

I would try to isolate the issue by trying a few things. If it were me, I would inspect the slide and frame rails for galling. If nothing stands out, inspect the guide rod and frame to see if there are any indications of binding on the spring or where it contacts the frame. I would also insert the guige rod and spring into the slide and compress it as far as it will go. Does it touch the frame? If yes, you are good. I would also  check to see if the disconnector moves freely in the channel in the frame. If it is hard to compress. I would take everything apart to see if anything looks odd. Lastly, I would pull the guide rod and spring out, put the barrel in the slide and install the slide on the frame. Add the disconnector and rack the slide back and forth. If there is any weird resistance, I would call the smith that built it.   

 

You may also want to test if the horizontal impact surface was cut correctly. With the gun assembled, rack the slide. Place your finger on the barrel where it meets up to the breach face. If you can push the barrel down, you may have a problem. 

 

Good luck!

 

 

Edited August 25, 2019 by GringoBandito

[Powder Finger]

Sounds like barrel bump to me something wrong that wear is not normal tumbling not caused from early iunlock the barrel is the barrel it’s a tube that doesn’t change with lockup 

[Powder Finger]

Btw how many rounds on that barrel? Not many I assume 

[11MM]

Might post this down in the gunsmithing section. One of those guys might be able to look at the pics and see what might be happening (not me...). Who made the pistol? Not flaming them, just wanted to know if it was a mass produced pistol or a custom.

[ziebart]

Gringo,
Anything particular I should be looking for for coil damage? Not sure what google strings will get me there. I'm working through the rest of your suggestions now. Thank you, its very specific.

PF,

I don't keep track of round count, but I'd put the estimate between 5-10k. It didn't always do this. At first it was just very difficult to unlock. Turns out the bbl wasn't relieved for the extractor. 

What you said about the bbl and comp being a tube makes sense.

 

11mm,

I would rate this as semi custom. They sell off the self models, but I ordered one with a light rail. Now that you say it I realized this probably isn't the right section. 

[MikeBurgess]

Looking at the pictures it seems there is a bit of a bur forming on you barrel lugs that has been sheared off, likely there is not much clearance between your barrel and slide when it is unlocked, I would take a large stone or fine sandpaper on a hard flat surface and  carefully dress down the high spots that have formed on the lugs. you are looking to just bring the lugs back so they and the barrel hood are all on the same plane. 

[N3WWN]

Just throwing this out there:  Could the link be too long and forcing the lugs to be too high when going into battery and engaging prematurely?  (Total shot in the dark here)

 

[ziebart]

N3WWN,

How can I determine if the link is too long? Anything is possible.

 

I didn't see anything obvious from the first reply. I will spend some time looking up galling to ensure I'm not missing anything.

[Sparky]

Ziebart,

The wear you are having is not normal.  I've had barrels and slides with 80 thousand rounds fired

not look like that.  Get a second opinion from another gunsmith.  Not saying anything bad about

your gunsmith, but if it ain't right it ain't right.......

[ziebart]

I could get second opinion, but then I'm coming out of pocket to get it fixed instead of the warranty. Even if it's abnormal the OEM said its fine because there is enough engagement left.

[ehowell12]

I had a barrel / slide look very similar to that in wear - it ended up resulting in a cracked slide. The crack started from the front corner of the ejection port (follow the first lug around). 

I sent the slide back to STI to get it replaced, but they wouldn't because they said the barrel was improperly fit. I just had them toss it in their scrap bin. 

Basically, in my case, the barrel did not drop far enough to clear the slide, causing the two lug edges to be rounded. Thus, putting more stress on the lugs in the slide. 

Hope this isn't the case for you, but I wish I knew now what I didn't know then!

[Benji]

I would send to a different smith for a second opinion. 

[ziebart]

If the barrel wasn't fit properly and the slide already has some damage then what is the point? 

[N3WWN]

N3WWN,
How can I determine if the link is too long? Anything is possible.
 
I didn't see anything obvious from the first reply. I will spend some time looking up galling to ensure I'm not missing anything.

I've never measured it or had to change links, but I found this info:
https://forums.1911forum.com/showthread.php?t=138412

Sent from my SM-G950U using Tapatalk

[ziebart]

Thanks. Looks like I have a few more things to try. Always have a hard time googling gun stuff cause seems like most folks have different ideas of what is "right"

[ziebart]

On 8/30/2019 at 8:29 AM, ehowell12 said:

I had a barrel / slide look very similar to that in wear - it ended up resulting in a cracked slide. The crack started from the front corner of the ejection port (follow the first lug around). ....

 

 

You called it. I've got a half inch long crack coming from that exact same spot.

 

Smith drop shipped a new guiderod that was beveled on the back that seemed to stop the jams. Still tumbling bullets though.

 

I'm trying to get with Venom for a top end rebuild. Figure I need a new barrel, slide and comp. Any thoughts on if that is a waste and just scrap the whole thing?

[zzt]

Put the gun into battery- no ammo, no mags.  Press down hard on the top of the barrel ithat shows in the top of the ejection port.  If there is any movement, the link is too long.  You can also check to see that the hole in the link the slide stop goes into is perfectly round.  Some smiths want to use a #3 link, because that shows a 'perfect' fit.  However, unless everything else is perfect, the barrel will not be sitting on the barrel rest.  So smiths elongate that hole so it does.  Elongating the hole means the barrel is not pulled down as far as it normally would be.  There are other things that might case this.  If the bottom lugs were not cut deeply enough,  they ride on the SS and jam the top lugs up into the slide.  The effect is the same as too long a link, but more severe.  If you get movement from the barrel when you press down, it's the link.  If not, it's the bottom lugs. 

 

Your lugs were damaged by improper fit.  I would not use that smith again for any reason, especially since he is telling you to use the gun because there is 'enough' engagement left.  If you do you will eventually shear off the top lugs.

 

Since your slide is also cracked, you need a new top end by a competent gunsmith.  If you like your comp, it may be reusable.  It all depends on the threads on the new barrel.

[ziebart]

Thanks for the info zzt. The comp fit loose on the barrel so I'm sure the threads were cut incorrectly there too and not reusable.

 

Other than Venom, I'd need to do some research into who is willing to work on a busted gun.