This week at the range I started having a few light strikes (not sure if that is the right term) that would leave a mark on the primer but not fire. The round would fire on the second strike. I checked out my striker assembly and it did have some gunk in it (i think from cleaning with too much CLP). I cleaned it up as good as possible and put it back. Any advice out there as to if that should do it (haven't been to the range again yet). Has anyone else had this problem? Should I check anything else before trying it again? I'll be more careful not to get CLP into the striker area from now on and actually take it out and look at it more often, but I'm interested in other ideas.

Same thing happened to me on my Shield (cartridge test-fire 1-31-13). It took 3 trips to S&W. They replaced the striker the first 2 times...do you know you can`t order a striker from S&W parts ? The 3rd time they replaced the slide and barrel. It does appear that Winchester ammo is the main culprit but I have "never" had a failure to fire with my 40c. I would suggest trying some other ammo if you can get it and see how that goes.
Good Luck, John

Do you oil your striker? If you do that is your problem. Take your pistol down totally and clean it well, I bet this fixes your problem. Do not put any oil on the striker assembly. Dry lube only if you feel the erg.

Thanks for the ideas. I use the exact same ammo in my full size and never a problem, that's why I was thinking it was the striker or something. I did totally clean out the striker assembly and will try to keep it as dry as possible (didn't think of asking S&W for a striker but I did order a striker assembly from Midway since I have two M&Ps that it could go in - figured it wouldn't hurt to have an extra)

I think it was wise of you to order a strike assembly. When you take the old one out inspect it for gunk & debris. An oily striker will work okay on its own but it will attract & hold residue from firing. If you take it out & find that's the case then you'll have a spare once you clean it up. Make sure there are no burrs or dings on it because that, too could cause a problem with light strikes. Don't forget to clean the channel that the striker rides in before installing a new one. If the striker is dirty then assume the channel is, too.

A test you can make on striker strength is clear the chamber, jack the slide, then put a pencil down the barrel eraser side down. Dry fire & see how far the pencil flies out. If it just barely clears the muzzle then your striker is too weak. Mine will jump all the way out a good six inches or more on both my FS 40 & Compact.

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Former USN, Retired US Army

Had a couple of early guns that started light striking. Got replacement strikers and you could see a small buildup on the sear pad that would give them slightly more travel. All the later guns I have got have this striker in them. S&W did send me the striker at the time but might be just because I was a dealer.