Author Topic: CZ 97 BD Trigger Job Recap  (Read 8851 times)

Offline PappaWheelie

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CZ 97 BD Trigger Job Recap
« on: June 16, 2016, 10:02:00 PM »
     My long-awaited (106 days on special order) CZ 97 BD finally arrived, and is simply beautiful, with its “cheese grater” (Cajun Gun Works terminology- love it!) thin aluminum grips and totally elegant proportions, sculpting and faceting.  I submitted a Customer Testimonial at CZ-USA’s 97 BD webpage after my first trip to the range: http://cz-usa.com/product/cz-97-bd-45-acp-black-aluminum-grips-3-dot-tritium-night-sights-10-rd-mags/
-see also my writeup of the incomparable CZ 2075 RAMI BD below the Product Description at: http://cz-usa.com/product/cz-2075-rami-bd-9mm-black-alloy-3-dot-tritium-sights-14-rd-mags/
The CZ 97 BD, unlike the CZ 97 B, comes with the highly curved black trigger like the one that also came on my CZ 2075 RAMI BD; CGW offers an argent “OEM ‘Thick’ Trigger” (same as the one that comes stock on the CZ 97 B and, per the illustration on my owners manual, at one time also came on the BD) that increases trigger reach by virtue of its reduced curvature, and its more blunt tip significantly increases fingertip comfort.  Mounting the two triggers side-by-side on a pair of matching trigger pins to align their holes clarifies ~4mm forward relocation of the trigger’s belly in the case of the “OEM ‘Thick’ Trigger.”
 
I have glove size XL hands, and the CZ 97 BD’s trigger reach, ~1/8” longer than the seeming “global standard” (the Colt 1911) per the RealGuns review, is helpful ergonomically but not as much as I’d like. The first chance I got I swapped out the trigger, springs, etc. using CGW’s Short Reset Kit, Reduced Power Trigger Return Spring, and Floating Trigger Pin.  This, via the “OEM ‘Thick’ Trigger,” brought my trigger reach to the same as that of the CZ 97 B, the global best-in-class for all but the smallest hand sizes: my wife has quite small hands, and she reaches the SA mode trigger perfectly.
 
This, my 2nd trigger job, was a breeze, and I learned a few things that may potentially be of benefit to others. 
 
Firstly, the CGW “Slave” sear cage pin worked best for me with its rounded end doing the work of displacing the Sear Cage Pin, i.e., oriented left, to enter, as required, from the right towards the left.  The difference was substantial (I tried the other, flat face first, orientation originally and gave up), particularly near the end of its insertion where it enters the Decocking Lever (#61 in the parts diagram): the bullet-nosed end provides sufficient “pointiness” to align the variously spring-misaligned holes it must enter.
 
Secondly, the Sear Cage doesn’t require complete disassembly as suggested by the NC Gunowners Ongoing review – CZ 75 SP-01 Tactical blog, http://www.ncgunowners.com/forum/showthread.php?tid=42855&page=3
-or the fussy full reassembly, working right-to-left, as also detailed there, to install the CGW Short Reset Kit’s Firing Pin Block Lever.
 
My CZ 97 BD’s trigger was so excellent “out of the box” that I decided to simply inspect the sear’s trigger engagement “OD” with a jeweler’s loupe to see to what extent polishing of machining marks might be warranted.  Like the Hammer’s SA tooth, it was seen to be nearly flawless, meaning Sear disassembly for polishing would largely be a waste of time.  So I decided to replace the Firing Pin Block Lever (hereafter FPBL) and reassemble it and its tiny Spring only, leaving the Decocking Lever, Sear, and their Springs intact in the Sear Cage as a significant “fussy labor” savings.  This entailed merely moving the Slave Pin leftward far enough to remove and replace the FPBL, then moving the Slave Pin back through the FPBL, leaving a gap to the inner wall of the Sear Cage through which the tiny hairpin FPBL Spring can be inserted, using tweezers, far enough to enable it to be pulled the rest of the way down (to where the Slave Pin can enter its loop) using a dental pick or a toothpick.
 
The FPBL features a “dovetail-section,” or undercut, face groove that acts to capture the hairpin FPBL Spring’s rear leg against the RH face of the FPBL, thus biasing it CCW (as viewed from the RH leftward): it’s important to assure the proper nesting of the Spring’s rear leg in the FPBL face groove (a dental pick can lift it into place if not) in order to secure proper Firing Pin Block function.
 
I did do some token polishing of the Hammer’s SA tooth before reassembly just because I could, but I don’t think the original surface had enough texture that such polishing could result in a “feelable” difference.  The trigger was stunningly smooth and crisp as shipped, as if produced on all new tooling.
 
I would like to mention that I’ve read several reviews of CZ BD pistols that attributed detectable trigger “grittiness” to the presence of the decocker hardware.  My CZ 2075 RAMI BD had such, but its Hammer’s SA tooth had a photographically documentable broach mark about 5/8 of the way from root to tip, a testimony to lax tool change practice; polishing this machining mark to near invisibility completely removed all traces of grittiness.  Beyond such subjective testimony, however, simple removal of the Slide and observation of trigger actions (both DA and SA) reveals absolutely no interaction between trigger pull and the decocker parts.
 
Replacement of the Trigger Return Spring with CGW’s Reduced Power Trigger Return Spring is facilitated by the short dummy trigger pin that CGW provides with its Floating Trigger Pin, to hold the Spring in place with the Trigger as it is pushed, against the Spring’s “hairpin” closing bias, into place where it can then readily be displaced by the Floating Trigger Pin itself.
 
I didn’t replace the Firing Pin Block Spring with the CGW kit spring because it (the latter) dragged heavily in the spring bore.  CGW assured me that this is deliberate, and that with over 20K (!) of them sold, none have been problematic.  The CGW spring is to be “screwed” into place, but the considerable OD friction, besides representing a needless wear opportunity, effectively shortens the spring’s working length thus increasing its effective spring rate.  If/when I ever pull my Firing Pin Retaining Pin, I may just shorten the stock Spring a bit to lower its preload; the two springs don’t appear to exhibit very different rates to begin with, but the CGW spring has substantially shorter free length.
 
I didn’t get pre-trigger job force measurements, but after swapping all but the one CGW spring the CZ 97 BD’s very nice new pull values are 5.4 lb. DA and 2.5 lb. SA, measured at the trigger’s tip for consistency.  I used my Rapala digital fish scale, pulling on an elongated “C” shaped steel rod having slightly concaved trigger engagement  “socket” on the pistol engagement end, a testimony to my latent blacksmith genes.  The hollow was hammered into shape before the bending into the “C” shape, obviously…
 
What a work of art is the CZ 97 BD!  Its very narrow grip width feels more like a single stack pistol than the 10+1 double stack powerhouse it really is, but its side view proportions are unmatched and its ergonomics are much more excellent for bigger-than-average hands than any other .45 ACP, IMHO.  The narrowness makes concealed carry a practical possibility, given a dual clip holster like the Crossbreed SuperTuck which, incidentally, I’ve requested to be provided in CZ 97-specific embodiment.
 
« Last Edit: November 10, 2016, 02:04:30 PM by PappaWheelie »
Member, Gun Owners of America
CC: CZ 2075 RAMI BD in PappaWheelie Invisible 15 Round RAMI Holster
Homeboy: CZ 97 BD, Underwood 45 Super 120 Grain Xtreme Defender ammo
UBG: CZ 75 SP-01 Tactical Urban Grey Suppressor-ready
-all w/ CGW Short Reset Kit/1485-T2 Disco, 5 "Thick" Trigger, polished SA tooth

Offline jwinch2

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Re: CZ 97 BD Trigger Job Recap
« Reply #1 on: June 17, 2016, 09:39:59 PM »
Incredible write up.  Thanks for that!