CZ P-07/09 OEM Hammer modification question

[Earl Keese]

I'm not an avoid shooter but the accuracy I'm seeing with my Duty P07 .40 pistol is better than I expected.  The pistol came with adjustable sights I've adjusted so the POA and POI intersect at 20 yds using 165 gr HST JHP ammunition.  I'm getting 3 shot bench rest groupings of 2.5" - 3.5" at this distance.  My reworked Sig P6 is identical and Sig P220 is only a bit better (2"-3") with carry ammunition on a good day.

My only quandary left is that it's SA break stills feels soft to me but isn't bad enough to kick the gun out of bed over.  Frankly, forum inputs vary enough that I'll find a tuned P07 or P09 pistol and make a direct comparison before I change it much more.  I live in the GSP SC area and have call back requests in at our local range and several gun shops.  Thks, Larry     

The mechanical accuracy of the P07/09 platform surprises a lot of new owners. They are capable of impressively small groups for a production pistol. The soft/rolling SA break is characteristic of the platform as well.

[Larry F]

I working to get my SA wall resistance to the point I think it's safe to use as a truck carry gun - not competitive shooting.  Where I'm at now is 7.5# DA measured trigger pull weight and the SA is at 4.25 #.  Of the 4.5# SA, I'm measuring 2.25# in take up to a wall and an additional 2# to break thru the wall.  My SA pull weight was 3# and I couldn't measure a wall with my RCBS spring scale.  To get the SA to this point I've worked thru the blue, the natural, and lastly the red CGW sear springs, 2 mainsprings and an over sized roller to reduce hammer roll-back to .008" measured at the hammer ring.

ScO - I'd say you're a better tuner than me with the results you're reporting.  Thks, Larry

[Earl Keese]

I working to get my SA wall resistance to the point I think it's safe to use as a truck carry gun

It was safe from the factory.

[SI VIS PACEM PARRABELLUM]

I have a question for Larry F. Are we talking about one P-07 or 2 p-07's that you have. Are we talking about the one mentioned in an early December post you paid your friend $250 for because he needed some Christmas cash or is this the one you mention in a January post that you traded an old set of golf clubs for???

https://czfirearms.us/index.php?topic=120503.0  post #14
https://czfirearms.us/index.php?topic=120890.0  post #4

[Larry F]

Good question - simple answer- my introduction to the CZ pistol world was thru horsetrading with a friend: progressed thru interest, offers, counter offers, buying agreement, second guessing, reversal, and then recognizing the other had something we both might be able to put to better use.

I see from your posting activities that you know your way around this pistol and would appreciate your input on another issue I've posted about and have yet to resolve.

My pistol had a outward bow in the polymer frame below the ejection port and had increased the frame to front insert gap that seems to be commonplace with this pistol.  The short slide stop spring leg was only partially seated in the frame causing the bow.  I made a quick fix by reseating the leg in the frame and pushing the frame back into shape as best I could.  I then realized the leg was still binding in the the cylinder it sits in and would probably back out as the slide stop was taken out and put back into place and the action's cycling back and forth could be amplifying the situation.  I pried the spring out of the frame and launched it somewhere in my shop.  I adjusted the new spring to fit in the the insert channel and the frame bushing and installed it by positioning the long leg under the front cross pin (took an notched screwdriver and 4 hands) as the last step to get a best practical fit.  I also beveled the leading edge of the slide stop pin so it slides under the spring with thumb pressure and touched the corner the spring crawls over when the pin is pulled out.  Lastly, my ejection distance was greater than I was comfortable with and I tried unsuccessfully to source a new 40 caliber recoil spring and am using a flat wire glock recoil spring and have trimmed it to produce a shorter ejection throw and maybe lessen impact loadings thru the slide stop pin.  I've now got the frame pretty much back into it's original shape and can only hope i've fixed the problem.

I've got a newer style front insert assembly the eliminates the L shaped leg and holding it in reserve.   

I know that MI4ME has an identical pistol to mine that he's used successfully with hotter ammunition and extreme ejection distance and hasn't had this problem.
Any thought on this issue and what I should consider?  Thks, Larry   

[SI VIS PACEM PARRABELLUM]

Interesting answer. Pretty good word salad anyway but no cackle at the end. You know you have 5 threads going regarding this pistol that could have been condensed into one and saved a bit of confusion. I answered part of this in the thread where you brought up the frame insert.
 You have an early DUTY model pistol and the long and short of it is there were issues with a large portion of them. The bulge issue was partly related to the leg on the slide stop spring but not all of it. CZ recognized a flaw in the polymer formulation on the early guns and it was rectified in the 2nd gen models along with several other changes including carry beveling the slide and frame, interchangeable backstraps, metal sights with a set screw on the front, nitride finish on the slide, and front serrations. I may have missed something but you get the idea.
So the bulge had a twofold problem.
As to the ejection issue CZ used the factory blue flat wire recoil spring both on the 9mm and the .40 S&W models. If your ejection distance is too far or too short then you simply increase or decrease the spring rate till it's acceptable.


https://czfirearms.us/index.php?topic=120640.0

[Larry F]

Thks for the quick response.  My tact in dealing with a problem is is break in down into smaller elements that can be addressed individually : i.e. the multiple threads.  I've read the 2nd generation improvement boiler plate and know the basics of recoil spring adjustment.  What I'm hoping for from guys like you is if there is something I've overlooked in fixing the frame issue as CZ has refused to exchange the frame for a replacement.  Thks, Larry

[SI VIS PACEM PARRABELLUM]

Thks for the quick response.  My tact in dealing with a problem is is break in down into smaller elements that can be addressed individually : i.e. the multiple threads.  I've read the 2nd generation improvement boiler plate and know the basics of recoil spring adjustment.  What I'm hoping for from guys like you is if there is something I've overlooked in fixing the frame issue as CZ has refused to exchange the frame for a replacement.  Thks, Larry

Well at some point mods will come along and put the stop to the multi-threads dealing with more or less the same issue, issues, pistol.
There is nothing more that you can do to that gun other than maybe install the upgraded front insert and hope for the other issues such as much worse frame bulge or the detaching of the trigger bar spring from the frame.
10 years ago CZ would have gladly replaced the ENTIRE pistol under warranty free of charge and they did many mine included. At this point they are under no further obligation as the five year warranty expired many moons ago.

[Larry F]

I have to keep reminding myself that I'm trying to improve a budget grade pistol and there is a practical limit on how much better I can make it and expect I'm close to that point.

Thks for putting up with my approach and style in using this forum.  Larry