M&P 40 Light strikes

[aspenvalley]

I am getting light strikes in my M&P 40. I think its the striker channel needs to be cleaned out. I can't for the life of my figure out how to get it apart. I looked on Youtube and I am sure not following.

Can someone tell me what I am missing? I hope there is just something simple I am missing. While I have it apart should I change or upgrade the striker spring?

[SDARFAN]

Have to depress the striker sleeve down then slide off end plate.

[skosh69]

Apex Tactical has the best videos to show how to detail strip an M&P

https://store.apextactical.com/WebDirect/Products/Details/191850

Follow the 3rd one regarding the USB

[smak28]

Apex Tactical has the best videos to show how to detail strip an M&P

https://store.apextactical.com/WebDirect/Products/Details/191850

Follow the 3rd one regarding the USB

This. Very easy to see and follow.

[etwinam]

I had this problem too, it turned out to be the striker block connection, so now I have a brand new Apex Striker block and a new firing pin assembly. It wouldn't hurt to clean out the firing pin Channel, I used Q-tips and cleaning rags.

[smak28]

Are you using steel, aluminum, or brass cased ammo? New or reloads? Steel & aluminum have hard primers where polymer pistols are known to possibly have light strikes.

[aspenvalley]

It happens with my reloads using CCI primers and with Hornady XTP with I use for Home defence. Firing it a second time it normally goes off.

[smak28]

I'm not an expert on the primers, but here's a thread mentioning CCI primers are the hardest, so sounds like your primer may be the culprit.

http://smith-wessonforum.com/ammo/137156-hard-soft-primers.html

[aspenvalley]

I don't think its the primers. They work fine in my G19, cz75bd, CW9, and Ruger Security Six.

I was able to get the striker out after watching the videos posted. I am not seeing anything that looks like a problem. It seems to be the older striker design with the 2 part cup to retain the striker spring. Should I upgrade and/or replace the spring?

[smak28]

I would think the Apex upgrades, as etwinam mentioned, should help increase the power of the firing pin striking the primer.

Here's a post from forums.1911forum.com:

https://forums.1911forum.com/showthread.php?t=226666

#10 Old 03-08-2009, 08:17 AM
RetiredRod's Avatar RetiredRod RetiredRod is offline
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Join Date: Jun 2002
Location: Springfield, Missouri
Posts: 12,246

As a reloader who occasionally has gotten light primer strikes, is it possible that you didn't seat your primers deep enough? It happens. First strike seats the primer and second strike pops it.

[rsrocket1]

Take a magic marker and color a few rounds completely. Load the rounds in the magazine and cycle them through.

Each time, look to see if the slide has closed 100%. Then check the cartridges to see if there is excessive ink rubbed off.

If the round is 99% in chamber, you will still be able to pull the trigger but he slide face is not flush against the head of the case and you will get an off-centered light strike.

You can try this with an empty case. Put it in the magazine and carefully ride the slide until it is about 1/4" from fully locked. Slowly move the slide forward while pulling the trigger. You will find a point where you will be able to pull the trigger and the slide is not 100% forward. When you remove the empty case, you'll see a light second strike mark off center.



As you say, it could also be a gunked up striker channel, but that would cause light strikes with any ammo, not just reloads.

You could also remove and clean out the extractor cavity which may prevent the claw from pushing out and allowing the case rim to cleanly slide under it.

[aspenvalley]

Iam getting light strikes with reloads and factory ammo. I don't think its the primers or the seating depth as I am not having light strikes with any of my other handguns using the same primers. I will look into upgrading the striker spring. Thanks for the help.

[smak28]

...light strikes with factory brass ammo in the M&P also? That does change things as that does eliminate the primer issue. If that's the case and you've cleaned out the striker channel, definitely try upgrading the striker spring.