Please explain how this would make the gun dangerous?
I am do not know if you are asking a serious question or being smart. I will take it as you really want to know.
The striker block is a drop safety, basically just like a Glock this safety is being pushed down at all times (unless you pull the trigger)and in the way of the striker so the striker can not hit a primer. Even if the sear slips from the striker there is a tab on the striker that will run into the striker block keeping the pistol from discharging unless you are pulling the trigger. When you pull the trigger the striker block is pushed up and out of the way allowing the striker to move forward when the sear releases it.
Were the problem would have most likely shown up first is in the striker block spring. This small part would have rusted to the point of weakening or even broke. One safety functions check is to make sure that safety block is free moving and springs back into place after it is pushed in and let go. You can do this on your own M&P's/Glocks/XD's by taking the slide off and flipping it over. Take a punch and push the button in, then let it go. Does it snap back into place. Functions check OK.
The second possibility is that the rust in the striker block hole will continue to grow and get worse. Once there is rust it will not go away on its own. So the rust would get to the point were it could slow down or even make the striker block get stuck in its hole. Either way the rust is not good, and I have seen this on other Shields before, but never this bad.
Third issue could arise that the finish on the striker seemed like it was peeling almost. Especially on the tab that would contact the striker block in the event a failure happened. If the tab were to be weakened enough maybe it could allow the striker enough additional movement that the striker could ignite a primer. Or even get stuck becoming jammed in between the striker channel and striker block.
For some of the comments that the wonder if he did this on purpose or is trying to get something from S&W. This customer did not know about the rust until I called him and sent him some pictures.
I told him to call S&W. I told him that I would not carry the pistol like that and would immediately take it out of service. As a gunsmith if I feel it would not be safe for me to use or give to my loved ones then why would I expect the customer to find that acceptable. I do not have any reason to believe the customer did this on purpose at all. But I do not know him any better that I know anyone on this forum. I have to take him at his word.
Look even if you do not know me, you can look up who I am and what my reputation is. What I do know is, that I touch an awful lot of these pistols and get to take them apart. This is not the first time I have seen rust in or around this safety. Before it was just so small an amount one couple simply just wipe it away and make sure to re-lube the area. This one was the worst one I have seen, and I wanted to share it. You should add this information to your toolbox for your inspections. Take the striker out and shine a flash light in the striker hole and examine your stuff. Hopefully you never have a problem, but if you do you will thank me you were able to find it.
Yes it would take time to get to the point of real damage. Or to be real dangerous. But I would not carry a gun in this condition and neither should you. Why wait try to catch it early or prevent it from happening. Thats why I posted this originally.
