Fixed

[Joseg1320]

Found the issue, thumb was hitting slide lock when the gun recoiled. Fixed my grip and haven't had an issue since.

[seal20]

I'm guessing your thumb is pushing up on the slide stop lever.

[ojisan]

Is your ammo is a wide mouth hollow point?
Some HP ammo can be so wide that as the next round in the mag is coming up, it can push the slide stop up.
I have not heard of this problem on the Shield but I have seen it before on other guns.
How to check?
Remove slide, insert full mag of this ammo and see if the bullet would hit the tab on the stop that pushes the stop up.
If so, the fix is a brand of ammo with a narrower bullet.

[Joseg1320]

I'm guessing your thumb is pushing up on the slide stop lever.

I just checked my grip on the gun and my thumb is about 3/4" away from the slide stop lever. I would need to grab the gun in an awkward grip to be able to push against the lever.

Is your ammo is a wide mouth hollow point?
Some HP ammo can be so wide that as the next round in the mag is coming up, it can push the slide stop up.
I have not heard of this problem on the Shield but I have seen it before on other guns.
How to check?
Remove slide, insert full mag of this ammo and see if the bullet would hit the tab on the stop that pushes the stop up.
If so, the fix is a brand of ammo with a narrower bullet.

I was using Federal FMJ 180 gr.

[ojisan]

I'd still check.
It only takes a minute.
Some FMJ Round Nose are pretty wide up front.

[Joseg1320]

I'd still check.
It only takes a minute.
Some FMJ Round Nose are pretty wide up front.

I removed the slide and inserted a mag and the bullet doesn't touch the tab, but I can see where a bullet would touch the tab if I move the bullet slightly forward. I'm wondering if the round wasn't seated all the way back in the magazine and that caused the bullet to hit the tab on the way up.

[squeeze]

Joseg1320
I have 2 9mm Shields. Shoot the gun using one hand. That way you know you are not pressing on the slide. My guess is that you are. When it locked back; where was the round that was supposed to have been chambered? Was it caught under the feed ramp or in its proper place?

I took my dremel and used rubbing and/or polishing compound to polish the feed ramp. Both of mine were not very smooth. Maybe even start with a pencil wrapped with emery paper. Go at them until the shine (and keep them that way!).

Also; take your mags apart and clean them. Make sure the plastic plate moves up and down freely. One of mine constantly sticks while loading. Mark the mag that is being used when you have a FTF.

As suggested; some hollow points a really broad where the pointy end is. You don't want to have an unreliable gun. Especially the Shield which is often a CCW. Since I have 2 of them; let us/me know what you found and or solved.

[Joseg1320]

Joseg1320
I have 2 9mm Shields. Shoot the gun using one hand. That way you know you are not pressing on the slide. My guess is that you are. When it locked back; where was the round that was supposed to have been chambered? Was it caught under the feed ramp or in its proper place?

I took my dremel and used rubbing and/or polishing compound to polish the feed ramp. Both of mine were not very smooth. Maybe even start with a pencil wrapped with emery paper. Go at them until the shine (and keep them that way!).

Also; take your mags apart and clean them. Make sure the plastic plate moves up and down freely. One of mine constantly sticks while loading. Mark the mag that is being used when you have a FTF.

As suggested; some hollow points a really broad where the pointy end is. You don't want to have an unreliable gun. Especially the Shield which is often a CCW. Since I have 2 of them; let us/me know what you found and or solved.

I'll take a look at the feed ramp. If the problem occurs again, ill make sure to inspect it while it's jammed instead of just racking the slide again and continue shooting like I did last time.

Do the mags need any oiling? Or just taken apart and cleaned with gun cleaner?

The sad thing is I purchased the shield because I wanted to use it for CCW, it's my first and only gun, when it jammed up on me I felt so disappointed because what if it had failed on me when I actually needed it.

[SlowDrifter]

I removed the slide and inserted a mag and the bullet doesn't touch the tab, but I can see where a bullet would touch the tab if I move the bullet slightly forward. I'm wondering if the round wasn't seated all the way back in the magazine and that caused the bullet to hit the tab on the way up.

Just a thought, if the rounds have room to move forward in the magazine, they may do so with recoil. Recoil does strange things and the ammo in the magazine and the magazine attached to the gun don't move simultaneously.

[squeeze]

Take the mag apart and use a cleaner. NO OIL maybe a dry spray lube? Do the feed ramp 1st then check the bullet/mag while jammed if it repeats. Was this gun new or used?

[Joseg1320]

Take the mag apart and use a cleaner. NO OIL maybe a dry spray lube? Do the feed ramp 1st then check the bullet/mag while jammed if it repeats. Was this gun new or used?

It was new. I've taken it to the range twice. First time I put 50 rounds through it, no problems. Took it home and cleaned/oiled it. Second time is when I had the two failure to feed, I put 150 rounds through it. I wiped down the feed ramp but didn't really pay too much attention to it when I was cleaning the gun. I'll take it apart and inspect the feed ramp when I get home. I haven't cleaned the magazines. How often should that be done?

[Pupulepeter]

How did you lube it? Did you lube the magazine? I just pulled mine out and checked. The simplest reason I could find was a round not being fully seated in the mag tripping the lock. However, I have a 9mm, not a .40. Lubrication on the feed lips definitely would not help.

Where was the next round when the slide locked? If it was still seated in the mag then it was definitely you’re fault. If the round locked back the slide you would probably need to drop the mag to release the slide. It sounds like that was not the case. You also do not mention a jam, just the slide locking back.

How detailed was your cleaning? Could the spring that holds down the catch have been installed incorrectly or somehow disabled?

I wouldn’t blame the pistol. All have pretty much the same mechanism in place to lock the slide back. You said this was your first and only gun. I take it you’ve received training, have a proper grip and have eliminated yourself as a reason, but it’s worth asking. There is no shame if it was. It’s part of the learning experience with a new gun and why you train to develop muscle memory. I’m sure someone will come by with a more definitive answer for you.

[seal20]

When you shoot, I would bet your thumb is activating the slide stop. Even though it may look like your think is far enough away the recoil might move your thumb up enough to activate the slide stop.

I sold a compact m&p because of this very issue.

I don't have the problem on full sized m&ps

[Joseg1320]

It's the first gun I own but not the first one I've shot. There was no jam, just the slide locked back. Now that I think about it, it probably was me hitting the lock since the next round never chambered.

When you shoot, I would bet your thumb is activating the slide stop. Even though it may look like your think is far enough away the recoil might move your thumb up enough to activate the slide stop.

I sold a compact m&p because of this very issue.

I don't have the problem on full sized m&ps

I'm going to the range sometime this week again and I'll pay attention to my grip.

[Supersapper]

A few things before you go and start all of this extra work polishing and detail stripping:

1. Make sure you are cleaning and lubing the firearm in all of it's appropriate places after every shoot or every other time you go to the range. I've had to fix a lot of firearms in my time with folks and one of the most common I see comes from too little cleaning. Make sure the slide lock operates without resistance.

2. Take a few magazines with you. Maybe borrow one from the range.

Load them with 6 or so rounds and insert. Make certain the magazine is firmly seated and not loose. The idea is to eliminate the magazine as a part of the issue. I don't think it is here, but if the follower has something wrong with it, a second and third mag should eliminate the problem.