Need to clean up some hammer hooks

[Dave Gundry]

Hey all, I'd like to get some better engagement out of my hammer on my CZ SP01. I picked up a CZ Custom Shop hammer. Dropped it in and checked it out. I get ~3lb SA break, which would be great, but about 1.5 of that is trigger return spring force. Also, I've got .009-.010" sear engagement. The sear face is ~.030". I'd like to deepen the engagement to ~.020", but I don't have stones to do so. Hopefully deepening and squaring the notches will increase my pull a bit, but if not, I'd at least have some surface area to work with in the future, and less worry-some engagement.

So, can anyone recommend a decent (but hopefully inexpensive) stone to deepen and square the hooks? Also, how would one go about cutting a relief notch in the hooks? I'd buy the Brownell's $125 kit in a heartbeat, but thats a bit out of the budget and skill level at this point.

Thanks for any help

[Radical Precision Designs]

Hey all, I'd like to get some better engagement out of my hammer on my CZ SP01. I picked up a CZ Custom Shop hammer. Dropped it in and checked it out. I get ~3lb SA break, which would be great, but about 1.5 of that is trigger return spring force. Also, I've got .009-.010" sear engagement. The sear face is ~.030". I'd like to deepen the engagement to ~.020", but I don't have stones to do so. Hopefully deepening and squaring the notches will increase my pull a bit, but if not, I'd at least have some surface area to work with in the future, and less worry-some engagement.

So, can anyone recommend a decent (but hopefully inexpensive) stone to deepen and square the hooks? Also, how would one go about cutting a relief notch in the hooks? I'd buy the Brownell's $125 kit in a heartbeat, but thats a bit out of the budget and skill level at this point.

Thanks for any help

That is not a "gentle, easy" undertaking, even with the proper tools/stones/jigs. It is like a fast dance over thin ice ... Thread very, very carefully.

[Dave Gundry]

Sorry to be such a newb, but I don't see how deepening the hooks by .010" and cleaning up the surface the sear rides on is that difficult. Go slow, even pressure in the right direction, measure and test fit often. The only part beyond me is cutting the relief notch. I am not looking for a supermatch trigger that'll last tens of thousands of rounds.

Worse case scenario - I wreck the hammer, need to put the stocker back in and get a new sear to refit the safety...

[L9X25]

K,

Another thing to consider is that the CZ uses leverage to move the sear. Increasing the hammer hooks will significantly increase the length on pull on the trigger to make it fire. In my experience, these guns have short engagements for a reason and I have never experienced a problem as a result.

Good luck with your project.

[Dave Gundry]

Correct, but on the stock setup, the sear engagement was 100%, or ~.030". Which is also why it was a horrible trigger with 3 distinct creep points... you could actually see the sear start and stop while it was traveling across the hammer hooks...