TUNING the thumb safety

[swbrian]

I like the thumb safety and MAY use it for an excuse for a hard sear and a lighter pull. However, it seems way too easy to flick on and off to be a really useful thumb safety. CAN the thumb safety be tuned - to be harder to switch on/off? Thanks.

 

[Gunsmart]

A good gunsmith should be able to. I don't know any easy way to harden it. Another possibility would be to reduce it in size to look like the one in the shield.

 

[ejeli]

Very easy to do yourself by filing the notch. Remember it doesn't need to be deeper, just steeper angles on the sides.
e.

 

[swbrian]

I really dom't see how removing plastic in the slotakes it harder. It would make it even looser. I guess that I'd it's lose it's lose

 

[robotoid]

There was a thread at the MP-pistol forum under the gunsmithing section that had pictures, but the picture links are dead and the OP never got with me on my request to get them or host them.

 

[ejeli]

It's not the notch in the plastic. If you field strip the weapon and pull the pins to remove the sear assembly the safety will come with it. There you will see the notches that need reshaping.
e.
M&P40 Armorer Manual

 

[swbrian]

Thanks. OK - so it's tunable? Has anyone done it to good effect.

I ask, because if I install a hard sear and get a 4.25 trigger pull, a safety would not be a bad idea. One of my objections to the PPQ, is that yes, it has a wonderful crisp light trigger, BUT for a weapon with no manual safety, this MAY not be a great thing.

 

[Nakanokalronin]

I'm pretty mechanically inclined and have worked on enough pistols that when I got my FS M&P in 9mm, I immediately made the thumb safeties more positive in the on and off position. What it takes is filing of the notches in the metal where the detent springs into on the sear block. It's quite easy but you want to go slow and test often so you don't take off too much metal.

I'd do it to my Shield but the little tab on the outside is not big enough to make me want to make it harder to engage/disengage.

You can see the detent on the left sear block. You want it to go into the thumb safety "zig zag" notches a little more positively, but not enough where it makes it hard to push in the up or down position. Only modify the notches on the thumb safety.