Opinions please

[1bird]

          This question is for CZ 75 BSA : What is the one part in the trigger that has the greatest influence on trigger pull ? I understand that. Many things make up trigger pull weight, creep, reset etc but what one thing only has the biggest influence ? Talking factory trigger here, my thoughts are tool marks, roughness etc but just a guess. Thanks for your input  John

[The Guardian]

What is the one part in the trigger that has the greatest influence on trigger pull ?


Hammer spring.....factory is 20#.....keeping everything else stock you can go down to a 16#, makes a significant difference 

[jDeLaBay]

Besides the hammer spring, maybe hammer itself? If you're looking for an inexpensive upgrade the CGW reduced power trigger return spring helps too.

[M1A4ME]

Maybe I've misread/misunderstood some replies in previous threads with similar questions - but I though the hammer spring didn't have much to do with the single action trigger pull.  I thought that reducing the hammer spring weight/strength was more for the double action trigger pull.

I've changed out the only SA conversion I've done to a 15 lb. spring, but I think I'd ordered that spring already when someone mentioned it wouldn't have much effect.

Hopefully someone with more experience/knowledge will peek in here and correct me if I'm wrong.

I would think SA trigger pull would be affected by the trigger return spring (not much), the firing pin block spring (not much), friction of the trigger bar on the frame (more) and the smoothness/angle of the sear to hammer contact surfaces (more).

My Compact SAO conversion got some polishing on the trigger bar where it contacts the frame, a lighter trigger return spring and firing pin block spring, I removed the disconnector, added the SA trigger (don't think that had a real/feel effect) and installed the CGW race hammer and adjustable sear.  The trigger pull dropped to 2&3/4 lbs. and it's not yet broke in (about a box of ammo through it so far.)

I did not polish the hammer spring guide, the sides of the hammer or sear, the pin the hammer spring guide spins on where it connects to the hammer, the firing pin block or lifting arm or the bottom slots in the trigger bar where the spring arms sit to push it upwards.

[rhart]

Be  nice ifsomeone would measure SA trigger pull before and after hammer spring change so we'd know for sure. I think the HS affects SA pull - just not as noticeable as DA pull.

[The Guardian]

Even in SA the tension applied to the hammer & sear interface from the hammer/main spring is lessened significantly when the hammer spring is reduced to 16#. Pulling the trigger releases that tension whether it?s 20# or 16#......the latter being lesser tension, hence a reduced pull effort on the trigger in both SA & DA. SA is just the final stage of the DA trigger pull effort......think of two strong magnets (20# spring) stacked, now try to slide them apart......do the same for two weaker magnets (16# spring), less force is needed to separate them.....same general concept 

[RedLizard]

+1 on changing out the factory hammer spring to a 16# spring.
The best part is that it's easy to do and it's the only thing I do
to help me shoot all my CZ's with consistency.

[Earl Keese]

I have several CZ's (75's and a 97) converted to SAO. All of them use an oem hammer spring and CGW trigger return spring. With CGW race hammer, TS hammer, or CZC comp hammer the pull weight is between 2-2.5lbs. Without the Cajun return spring, pull weight goes up a half pound. Hammer hooks play a significant role in SA pull weight as well. One of the main benefits of SAO is the ability to use the stronger hammer spring for reliable primer ignition and compatibility with a Kadet - All while getting a nice clean crisp break on the trigger.
 A lighter hammer spring may be more beneficial with an OEM SAO hammer, but creep will be more noticeable the lower you go.

[briang2ad]

Depends what you want.  There are two pulls of course: DA and SA. 

SA has to do with the sear and hammer hook interface.  On many CZs this can be poorly done and give you a stagey pull prior to the break.  ALL CZs are made to 'cam' - but this camming can be uneven or gritty.  Shooting 1000 rounds can sometimes make this pretty good.  Use a O-Ring and dry fire the smooth out of it and you can help this also.

DA has to do with the mainspring weight AND smoothness.  You can dry fire and fire the HECK out of it and get a smooth DA pull.  Or you can AID this by detail stripping and polishing the hammer bar, pins, hammer strut, etc.  This can have a VERY major impact along with a 16/17 Lb mainspring without much else.  If you go lower, you then need an extended firing pin. 

Polishing and smoothing alone can also do MUCH to make the pull feel much lighter.