Warning: long post ahead. TL;DR: Was getting light primer strikes on Shield, removed striker assembly, it was dirty, I cleaned it, fingers crossed that fixes the issue.
Full post: So I have an M&P Shield9 v1.0 with APEX DCAEK and AEK trigger installed. It was installed by a professional gunsmith/M&P armorer when the gun was brand new, before it got to me (I purchased the gun, parts, and install service brand new all at once). Anyway, I've had this pistol since July 2017. In the time I've had it I've put approximately 1,000 rounds through it, with absolutely zero malfunctions of any kind, regardless of ammo. Well, that all changed recently. I was at the range with some family during Christmas, and I had some light primer strikes resulting in a failure to fire, about 3-4 light primer strikes within 200 rounds. At first I thought it may be the ammo since it was a really cheap Remington range ammo, and the gun was clean (I always clean my gun after every shooting session, so I'm always starting with a clean gun each session). After we finished up at the range and got home, I field stripped and cleaned the gun very diligently.
Fast forward to the next shooting session a month later, I'm getting more of those dreaded light primer strikes resulting in failure to fire. This time though I was using a multitude of ammo: Federal HST, Speer Lawman, and your standard Federal ammo from Walmart that comes in the red box. In 250 rounds, I had 4 light primer strikes, and it happened with each type of ammo. It would happen at random: first round, middle of a mag, didn't matter when it just happened randomly. This was very concerning given the multitude of quality ammo, so at that point I ruled out ammo as the factor and figured it has to be the gun.
Another thing I noticed during this session is that whenever I insert a fresh mag, I always give it a good smack with the heel of my hand to make sure it's seated all the way. Well I noticed this caused the slide to pop out of battery, which has never happened to me before with this gun in the 19 months I've owned it. For example, if I want +1 in the chamber and top off the mag, I rack a round into the chamber, eject the magazine, top the mag off with the last round, and then reinsert it back into the gun and give it a smack to make sure it's seated all the way. When I did that, the smacking of my hand on the bottom of the mag was forcing the slide to jump out of battery. Picture here: https://imgur.com/daJGcxK
After I finished shooting, I talked to the store's gunsmith on my way out. He said it was probably the Apex springs because Apex doesn't use good springs and told me to get Wolff springs instead. I told him the Apex parts were installed by a professional gunsmith who is also an M&P armorer, and he was like oh okay, hmm (with a perplexed look on his face). He said to give the gun a good cleaning (which I already did prior to the shooting session) and see if it happens again, and that he could look at it. He couldn't look at it that day because he was busy and I was on my way out anyway. He also said not to top the mag off and +1 in the chamber because it can damage the gun because it's putting to much pressure on everything, and that he got lots of police trade ins of other guns with similar problems...
I get home that night and research M&P Shield light primer strikes. Did the usual internet sleuthing reading through various forums, and most people said to disassemble and clean the striker and firing pin. All this time I was under the assumption that the rear sight had to be removed in order to do this, and never realized how easy it actually is to do. I've never once done this to the gun until now. Credit to this video here for teaching me how to remove and reassemble the striker: [ame]https://www.youtube.com/watch?v=6vJQuxBVplY&t[/ame]
So I do exactly that, and wow the striker, firing pin, and striker channel were pretty dirty. Tons of gunk, debris, oil, and pieces of brass shavings everywhere. I cleaned up the striker and channel, using q tips and patches to get all the gunk and debris out. I also ran some Q tips covered with Breakthrough Military Grade Solvent to clean it, because in my experience it's really good at cleaning up gunk and I noticed that it dries completely after just 5-10 minutes which is nice. It fully evaporates and doesn't leave anything left behind. Everything I've read said to leave the striker and channel dry, never lubricate or oil it.
Below are some pictures of how dirty it was. I went through dozens and dozens of Q tips to fully clean the channel out. After I cleaned it, the white plastic and the silver striker and firing pin were nice and shiny. I haven't been able to shoot it yet after cleaning it since I literally just did this yesterday. Hopefully just a dirty striker was the cause of the light primer strikes and I don't get any more of those malfunctions next time.
After cleaning and putting everything back together, I tried to re-create the slide popping out of battery when smacking a mag in, and I couldn't re-create the issue. So it seems fixed for now. I'm still not sure why or if a dirty striker would cause such a thing, or if it's a separate issue entirely, so I'm going to keep an eye on it in case it happens again.
I also decided I'm going to start cleaning the striker and channel as part of my normal cleaning routine. I never knew it was this easy to do until now.
Video and pictures below:
Video of my dirty striker: [ame]https://www.youtube.com/watch?v=exzcKpKXDiE[/ame]
Pictures:
Imgur: The magic of the Internet
Imgur: The magic of the Internet
Imgur: The magic of the Internet
Imgur: The magic of the Internet
Full post: So I have an M&P Shield9 v1.0 with APEX DCAEK and AEK trigger installed. It was installed by a professional gunsmith/M&P armorer when the gun was brand new, before it got to me (I purchased the gun, parts, and install service brand new all at once). Anyway, I've had this pistol since July 2017. In the time I've had it I've put approximately 1,000 rounds through it, with absolutely zero malfunctions of any kind, regardless of ammo. Well, that all changed recently. I was at the range with some family during Christmas, and I had some light primer strikes resulting in a failure to fire, about 3-4 light primer strikes within 200 rounds. At first I thought it may be the ammo since it was a really cheap Remington range ammo, and the gun was clean (I always clean my gun after every shooting session, so I'm always starting with a clean gun each session). After we finished up at the range and got home, I field stripped and cleaned the gun very diligently.
Fast forward to the next shooting session a month later, I'm getting more of those dreaded light primer strikes resulting in failure to fire. This time though I was using a multitude of ammo: Federal HST, Speer Lawman, and your standard Federal ammo from Walmart that comes in the red box. In 250 rounds, I had 4 light primer strikes, and it happened with each type of ammo. It would happen at random: first round, middle of a mag, didn't matter when it just happened randomly. This was very concerning given the multitude of quality ammo, so at that point I ruled out ammo as the factor and figured it has to be the gun.
Another thing I noticed during this session is that whenever I insert a fresh mag, I always give it a good smack with the heel of my hand to make sure it's seated all the way. Well I noticed this caused the slide to pop out of battery, which has never happened to me before with this gun in the 19 months I've owned it. For example, if I want +1 in the chamber and top off the mag, I rack a round into the chamber, eject the magazine, top the mag off with the last round, and then reinsert it back into the gun and give it a smack to make sure it's seated all the way. When I did that, the smacking of my hand on the bottom of the mag was forcing the slide to jump out of battery. Picture here: https://imgur.com/daJGcxK
After I finished shooting, I talked to the store's gunsmith on my way out. He said it was probably the Apex springs because Apex doesn't use good springs and told me to get Wolff springs instead. I told him the Apex parts were installed by a professional gunsmith who is also an M&P armorer, and he was like oh okay, hmm (with a perplexed look on his face). He said to give the gun a good cleaning (which I already did prior to the shooting session) and see if it happens again, and that he could look at it. He couldn't look at it that day because he was busy and I was on my way out anyway. He also said not to top the mag off and +1 in the chamber because it can damage the gun because it's putting to much pressure on everything, and that he got lots of police trade ins of other guns with similar problems...
I get home that night and research M&P Shield light primer strikes. Did the usual internet sleuthing reading through various forums, and most people said to disassemble and clean the striker and firing pin. All this time I was under the assumption that the rear sight had to be removed in order to do this, and never realized how easy it actually is to do. I've never once done this to the gun until now. Credit to this video here for teaching me how to remove and reassemble the striker: [ame]https://www.youtube.com/watch?v=6vJQuxBVplY&t[/ame]
So I do exactly that, and wow the striker, firing pin, and striker channel were pretty dirty. Tons of gunk, debris, oil, and pieces of brass shavings everywhere. I cleaned up the striker and channel, using q tips and patches to get all the gunk and debris out. I also ran some Q tips covered with Breakthrough Military Grade Solvent to clean it, because in my experience it's really good at cleaning up gunk and I noticed that it dries completely after just 5-10 minutes which is nice. It fully evaporates and doesn't leave anything left behind. Everything I've read said to leave the striker and channel dry, never lubricate or oil it.
Below are some pictures of how dirty it was. I went through dozens and dozens of Q tips to fully clean the channel out. After I cleaned it, the white plastic and the silver striker and firing pin were nice and shiny. I haven't been able to shoot it yet after cleaning it since I literally just did this yesterday. Hopefully just a dirty striker was the cause of the light primer strikes and I don't get any more of those malfunctions next time.
After cleaning and putting everything back together, I tried to re-create the slide popping out of battery when smacking a mag in, and I couldn't re-create the issue. So it seems fixed for now. I'm still not sure why or if a dirty striker would cause such a thing, or if it's a separate issue entirely, so I'm going to keep an eye on it in case it happens again.
I also decided I'm going to start cleaning the striker and channel as part of my normal cleaning routine. I never knew it was this easy to do until now.
Video and pictures below:
Video of my dirty striker: [ame]https://www.youtube.com/watch?v=exzcKpKXDiE[/ame]
Pictures:
Imgur: The magic of the Internet
Imgur: The magic of the Internet
Imgur: The magic of the Internet
Imgur: The magic of the Internet
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