Striker block not working

[horseman]

This was a used MP MM 4.25. It had been messed with. Sear was ground to nothing and had to bend the trigger against the stop to get it to go off. Replaced sear. Working much better. Was having light strikes and put in an extra power striker spring. Seemed to fix the problem for about 500 rounds. Today more light strikes. Maybe 6 or 8 out of 100. Cleaned it and it was indeed nasty. Cleaned my 40 Pro next since I was in the mode. Something different. I could push the firing pin forward without pushing the disconnect on the MM. It came with a bunch of parts including what appears to be an unused striker spring and the parts that holds them together. So I put that assembly in. No difference. The pin still goes forward. I can feel it dragging slightly which goes away when I push the disconnect button down. It came with Warren sights. Is it possible that little bearing that goes under the sight, spring and plate is missing or damaged? I can see part of the plate under the Warren base. Both striker assembly's I have are old style according to Randy's video (two piece plastic part). What is the fix for this and what happens when your striker block does not work? Thanks

[RWF]

Wow, no idea really, i would remove or slide over the rear sight, as you said and inspect the spring and the plunger. it would have to one or both pieces damage or unsafely modifed. i think the parts on the 40 should work on the 9 at least the spring plunger if you do find anything that just looks wrong when look at the "bad" part. and test it like that. good luck.

but i am damn sure no expert!

[beastfrog]

Could be the spring is kinked. Does the striker block depress and return smoothly? I would probably just take the rear sight off and inspect the spring and spring cap. Because of the timing involved if the sear was really messed up it may be that the striker block got damaged from the striker hitting it. Inspect and replace if necessary.

[SpcStn]

I've had the same issue in my M&P Pro 9. Turned out what should have been a sharp edge/90 degree shoulder on the striker block was "rounded off" and no longer prevented the striker from moving passed the striker block - it effectively nullified the striker block safety. This is not a good thing. I replaced the striker block with another one of the same type and manufacturer and I continue to keep an eye on it to ensure the edge/shoulder doesn't get rounded off again. What's puzzling to me is that I put the striker block in myself about a year ago and have less than 5000 rounds on it before I noticed it failed (I say "noticed it failed" because I don't know how long it was that way before I found it.). With relatively few rounds through the gun, I don't understand how the striker block edge could be rounded off (unless the material was bad or out of spec). So I'm curious to know if anyone else has had this problem.

Edited December 9, 2011 by SpcStn

[Dan Burwell]

You did try retracting the striker a bit to see if it would then engage? A lot of people forget that when you take the gun apart the trigger bar disengages the striker block as you remove the slide; if you do not reset it by pulling the striker back just a bit you can push the striker forward.

[horseman]

Well who knew. Dan, thank you very much. I did not know that. I could hear it click when I pulled it back just a little and then it functioned appropriately.

[Dan Burwell]

Well who knew. Dan, thank you very much. I did not know that. I could hear it click when I pulled it back just a little and then it functioned appropriately.