NP29 slide fails to lock after last round - any wisdom?,,other than get another gun..

plinkercases

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I did do a search and saw other problems (luckily which I don't have). It is a well used and reportedly problem free purchase. It did not like one brand of ammo and had several FTE's so at least I learned what to feed it. That's not problem.

However, it never once locked back the slide after the last round with all three mags I have - 1 mag is Norc and other 2 both different manufacturers.

I have heard of this before and tell of taking a screw driver to tweak the magazine so it engages the slide lock. can someone (who owns this gun perhaps?) let me know how I can address this issue. I want it to lock as designed... unless of course someone tells me the NP29 was not designed to do that...? Doubt it.

So any help is appreciated and thanks in advance.
 
OK it isn't the thumb as I am wise to that from other 1911's. Can you post a pic pointing to the "mag catch lip" just to be sure I bend the right thing... as I have never had to do this tweak before.
 
I did do a search and saw other problems (luckily which I don't have). It is a well used and reportedly problem free purchase. It did not like one brand of ammo and had several FTE's so at least I learned what to feed it. That's not problem.

However, it never once locked back the slide after the last round with all three mags I have - 1 mag is Norc and other 2 both different manufacturers.

I have heard of this before and tell of taking a screw driver to tweak the magazine so it engages the slide lock. can someone (who owns this gun perhaps?) let me know how I can address this issue. I want it to lock as designed... unless of course someone tells me the NP29 was not designed to do that...? Doubt it.

So any help is appreciated and thanks in advance.

Q) can you lock the slide back using your finger on slide stop ??

Q) have you added a buffer ? Ca you take it out

Q with a empty mag in, -- if you pull back the slide -- will it lock back
It did not like one brand of ammo and had several FTE's so at least I learned what to feed it. That's not problem.

What I have heard is the 9mm extractor is not very good, compaired to a name brand extractor ( any extractor will need to be tuned for best results)
9mm is different than the 45 and for $20-30 it will make a diference
 
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Does the slide lock back correctly if you rack it with an empty mag in the well? That's a first step. If it can't catch correctly under this situation then something is mechanically wrong. Look for the slide lock's finger not reaching the mag follower or the follower not pushing up the finger high enough. Since it's doing this with all three mags it would then likely be the finger on the slide lock isn't reaching down far enough.

If it does lock back bump the back of the slide firmly but not enough to cause discomfort and see if the slide kicks free. It may be that the slide lock notch has become peened so it's not catching well. Under firing it may be bouncing and letting the slide drop back.

And finally there is the more likely of the causes. And that is simply that the recoil spring is a bit heavy and the slide isn't cycling back for the full stroke. A lot of folks think springs become weak with use. But in reality they work harden and become stronger and more brittle. And that's why old springs tend to break instead of collapse. At least the better ones do. If they collapse and become softer then they were not good springs in the first place. Your recoil spring likely started out a little heavy or has become stiffer with use and needs a good replacement.

You can usually see this on a semi auto by the way it ejects the brass. You want to see a nice arc of the brass out at least a half meter to the side before it falls below the pistol. If it's dribbling out over the back of your hand the recoil spring is WAY too strong or the loads too weak for that spring. But that's pretty extreme and you'd likely be seeing a lot of stovepipe jams as well. But even at an ejection arc of up to a half meter that is still not that strong. I had a Beretta 92fs that was on the ragged edge which ejected the brass out to about 30 to 40 cm before it fell below the gun and it would only lock open about one in three times. A friend wanted it badly so he bought it from me before I got a new spring to try.

In your case you likely just need the stock 12# spring if using regular factory ammo. If you're loading up IPSC or other 130'something PF loads then you would likely need more around a 10# spring. A good source of direct to your door springs is Wolff springs out of the US. They do have a shipping fee but just add in a few other springs for your other guns and magazines to make the order up to around $100 and the shipping fee becomes more reasonable. Bring a few friends in on the order if need be to get the price up to that level or a little more. Wolff ships via USPS which converts directly to Canada Post so no brokerage fees are involved. Just direct to your door delivery.
 
"Just Having Some Fun" thanks and I can test your questions next weekend when I am a the gun's "House".

BCRider this spring theory sounds very likely as the shells don't get too far and a few just lop back onto my hat. I am using factory target ammo so 12# seems likely. Even when racking it to clear the FTE's with the goofy ammo it was a tough push.. tougher than I would have expected. And it has had some good use before I got it.

I have asked the previous owner if he had the same issue just to make sure there isn't some strange operator error going on...even though I am sure the thumb was clear... you never know. I will check out Wolff springs and then next weekend run some of the diagnostics mentioned here.

Thanks folks.
 
I have the same problem on my NP34... Only one mag does it though, so I'd love to hear some more suggestions... And what the heck is the "mag catch lip"? If I can bend crap to fix it, I will!
 
Great troubleshooting steps above. I just went through a similar problem with a Sig 226, which hadn't seen much use lately.
- The first hint was that NONE of the mags (two manufacturers) were engaging the slide lock, (ah, but keep reading!)
- I was able to engage the slide lock with my thumb while firing, so I knew the slide was recoiling back far enough (so not a light load)
- The slide lock was engaging when any empty mag was installed and slide pulled back.

So, I thought I had eliminated the mags (since they were all doing it), the load and slide movement, and the mechanism.

Then, as I was trying it for the third session in a week (obsessed with fixing it), I was loading a mag, and thought "thank goodness the mag spring isn't as stiff as on an M&P" - then it occured to me to stretch the spring. I disassembled the mag, gave it a free-handed stretch, and reassembled. "That's a bit stiffer - more like the Shadow I had". I loaded 5 into the mag, and lo-and-behold, the slide locked! I Stretched all but one mag spring, and loaded 2 rounds into each. They all locked back, except the one I didn't stretch! Stretching that one fixed it too.

So, in my case, my theory is that the weak springs weren't able to raise the slide lock fast enough to catch the slide, while shooting, but any manual rack of the slide was slow enough to catch it.

The oddest part was all six mags had the same problem. My technical training screamed at me that if it was a mag issue, at least one mag would still function properly. To have all of them behave the same, the problem had to be on the gun!

Hope you find your solution.
 
That's a nice fix sulisa. As long as the springs don't collapse again later from being compressed with full loads you've got a solution for your situation.

If they do sag a bit and the issue comes back I'd say it's time for new mag springs.

Folk,s such as Slavex, that shoot lots of rounds per year tend to regularly change out the recoil and mag springs just to avoid issues as seen in this thread. When we're beating on these things a lot they don't last forever.
 
more good suggestions. I cant wait to get the gun this weekend and try to sort it out. All 3 of mages are different but all not spring chickens ... pun intended... so that may be the issue.
Does Wolff springs have mag replacement springs as well? and how do you order them specifically... 9mm single stack etc.?
 
I had that issue on 1911 (Dominion Arms/ Norinco). Not always staying open after last round. Fix for me was bending the mag lip so it engaged the slide lock. I used a pair needle nose pliers to bend the mag lip. Has not been a problem since.
 
I have experienced this problem as well, and it would lock open on an empty mag while manually working the slide. I picked up a new slide lock and the issue hasn't reoccurred in approx 500 rounds.

Good luck!
 
Thumb thumb thumb... (imagine that like to old movie sound track)
Mia Culpa......Yup when working it through and doing some elimination stuff I realised that the NP29 has a slightly wider slide release than I am used to and I usually sit my right thumb on the safety . but on this gun then the tip/corner of my thumb just touches the slide control enough to keep from engaging fast enough. So re-grip and no problems with that issue.
But now still getting some stove pipes (when rapid firing) this time with Winchester bulk 9mm. so it has only really liked S&B. I will take the next steps there and get a new spring and perhaps replace the extractor. Any advice on that front?
 
Can you post a pic pointing to the "mag catch lip" just to be sure I bend the right thing.

And what the heck is the "mag catch lip"? If I can bend crap to fix it, I will!

The slide lock is pushed up by the mag follower as it comes up to the top of the mag body when the last round is stripped from the mag. The slide lock has a piece that sticks out over the front corner/edge of the mag body and the follower comes up and hits that piece to push up on the lock as the slide cycles back. Put an empty mag in your gun and cycle the slide back so it catches open. Look down into the ejection port and you will see the mag follower pushing up on the slide lock lever from the inside. The bending part is sometimes you have to tweak the point on the follower that engages the slide lock so it hits it correctly and pushes up far enough that the lock engages the slide when it cycles.


Mark
 
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