S/A Take Up Improvement

[Steve Menegon]

Say for example you only wanted to reduce the S/A take up on a 75B. You are happy with every other aspect of the gun and do not want to install any aftermarket parts. Would it be as simple (🙄) as building up the disconnector hook and fitting it?

Thoughts?

[Wobbly]

The problem is making anything longer usually involves welding of some form. Most forms of depositing metal involve enough localize heat to take the hardness and temper out of steel. Hardness makes the surface long-wearing; temper makes it tough.

So how would you extend the part? With epoxy ? It's not nearly hard or tough enough. You immediately get into a battle with cost. Yes it can be done, but generally at a cost 5 or 8 times what the CGW replacement part costs.

[Steve Menegon]

I agree with you Wobbly, but I was bored and thinking about the idea.

Epoxy would be used for a test molded/fitment piece. I planned on adding a cut to fit stainless steel brake pad shim. I have access to some amazing industrial strength epoxy compounds. Permanent bonding would be a non-issue. Marine Tech epoxy has a 5,000 psi bonding strength.

Just to clarify, I prefer all metal, but it is fun to think about. My other 3 CZ guns have CGW Pro Kits in them. I'm not opposed to getting the part or parts, but I just thought about that sole improvement I'd like and how I could do it on my own.

Thanks for your input.

[tdogg]

You also have to take into account the timing of the action.  You are advancing the trigger but if you don't alter the reset it may not function.

Cheers,
Toby

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[Steve Menegon]

I am with you Toby. I wanted to stop the pre-travel just before the FPBL begins to lift. In theory, it should work. 😁

[Steve Menegon]

To clarify, I will only test this out at my next range trip. Even if it functions perfectly during live fire, the disco is coming out. I needed to prove to myself it could be done.

What I did first was see if I could measure the distance inside the gun where the FPBL was just beginning to lift. I did this with an old wire spark plug gauge. See blue arrow in photo.

Once I roughly figured out that distance, it was tough to get it
 perfect, I looked to add that
 amount to a spare disco.

I cut a piece of stainless steel brake pad shim as close as I could. Pain in the butt. Cleaned everything after scratching up with 60 grit sandpaper. Mixed up marine tech epoxy, set in place, and squeezed close to distance needed.

I polished up all the internals while gun was apart.

I let it cure, removed excess, and finished it off. First test installed was a fail, but it was close.

Tore it back apart and removed material from the metal pad. For the experiment of it, I tried to pry off the metal pad. It was not budging. I felt confident to continue.

Second attempt was successful. Plenty to room for reset plus a bit additional. I had .143" take up in S/A where the FPBL was beginning to lift. New distance is .078". So all but half.

I took a picture with my 97 BD which I had installed the Pro Kit from CGW. S/A positions are close, but the Pro Kit in the 97 is amazing.

Why did I not just buy the CGW kit instead of spending the time doing this? The action in the 75 is just as smooth, but not as light. The S/A pull on the 97 is under 3lb. If I recall correctly it is closer to 2.5lb. The 75 is 3.5lb as is. When test firing it the first time I did, I was ok with trigger weight. As I said previously, I just wanted less S/A take up my 3 CGW equipped guns exhibit.

It can be done and does work even if it will only be temporary.

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[OneWay]

A bunch of engineers designed the trigger system based on the required amount of movement in a number of fire control parts, not just the trigger.  The closer you come to no takeup, the closer you come to problematic reset. And the closer you might come to automatic fire.  All these things can be tweaked, but the platform is designed to work reliably with some free movement.  Familiarity with the feel of trigger operation is a good way to approach it, in my opinion.
OW

[Steve Menegon]

Yes, a bunch of engineers designed a trigger system, but things don't always get built as designed. I'm sure you are aware of all the possibilities of deviations from designs. Perhaps the safety margin was excessive compared to blueprints, I cannot say. All I did was reduce the free play somewhat while still allowing every aspect of the gun to function as designed. I may not have explained myself clearly and succinctly in my first couple posts.

In any case, it worked. Flawlessly.

[M1A4ME]

Years ago there was a thread on the forum started by a member that did modify/make some internal P07 or P09 parts to alter the way the action worked. 

Don't remember his name or the thread name but it might show up with a search.  Then again, even if it was found the pictures may be gone from it.

[Steve Menegon]

M1A4ME,
My little test came about because I was told I had to buy multiple pieces/kits to accomplish what I wanted to do. Having worked on my other 3 CZ guns and studying the action, I could see no reason this little test to take some freeplay out of the S/A wouldn't work safely and consistently.

I have no desire to make parts. 😁 I stated earlier I would try this and proceed to go the CGW route if so desired. I am leaning towards leaving the 75B as is, that is until I shoot the guns I installed the CGW kits. 🙄😍

[M1A4ME]

M1A4ME,
My little test came about because I was told I had to buy multiple pieces/kits to accomplish what I wanted to do. Having worked on my other 3 CZ guns and studying the action, I could see no reason this little test to take some freeplay out of the S/A wouldn't work safely and consistently.

I have no desire to make parts. 😁 I stated earlier I would try this and proceed to go the CGW route if so desired. I am leaning towards leaving the 75B as is, that is until I shoot the guns I installed the CGW kits. 🙄😍

I know what you mean, I think.  I've got an M&P Performance Center .40 S&W pistol.  I shoot it and I think, Trigger's not bad at all.  I can live with this."  Then I shoot one that has an Apex trigger kit in it and when I pick the PC gun up the trigger just doesn't feel right.  I know right away it's not an Apex trigger and I know it could be better.  Not hard at all to get spoiled.

[Steve Menegon]

You are on the money M1A4ME, I just have to leave the other CZ stuff at home when I shoot the 75B. 😁 Yes, we do get spoiled.

One of my shooting buddies had not shot my SP-01T with all the goodies in it. For whatever reason, I did not have the SP-01T with me when we hit the range together. Recently he had the opportunity. He shot a couple mags, never commented on accuracy, comfort in hand, or anything other than "That trigger is amazing, what did you do?" He and another guy will shoot the 75B tomorrow. It will be interesting to note his reaction.

[M1A4ME]

Enjoy the range trip.  Always great to open someone's eyes to what a nice CZ feels and shoots like.