CZ Open Build Theory

[CZ75SP01Marc]

I currently have a hard time to get the holes for my optic mount drilled into the SP01 frame.

I changed to Carbide drills which works, no I have the problem to get a tap to cut the thread.

Anybody has a source where I can acquire a tap which will work in the obviously heat treated frame material.

[AcePrater]

Ok, I'm on this train now. I've been lurking for a while. I just sold and S2, got my SP-01 safety model back so I have $$$ to build it now. The SA just didn't compare to my SAO gun, I have minimal interest in DA/SA. I thought about building up my 75B limited, but the beavertail on the 01 just feels so much mo bettah and that was the ultimately the deciding factor...

about to order a threaded barrel and comp. Really like the long square comp, where did you get that one?

After that SAO/Race Hammer, springs and magwell. Sights/optic will be last.

[RonnieJr]

I bought the SJC 11 port comp from Shooters Connection. You can also order straight from SJC. 

[Rusl]

14 hours ago, CZ75SP01Marc said:

I currently have a hard time to get the holes for my optic mount drilled into the SP01 frame.

I changed to Carbide drills which works, no I have the problem to get a tap to cut the thread.

Anybody has a source where I can acquire a tap which will work in the obviously heat treated frame material.

 

I just used normal hss drill and tap, I actually was surprised at how easy it was to drill, I did use a large drill press though.

[Rusl]

Ok, today after around 300 rounds through the gun with the new optic mounted the screws came loose, I had blue locktite on them but I didn't de-grease the holes/screws before assembly so that may be the issue, I have degreased every thing and reassembled it, is there any thing else you guys are doing different to stop the mounting screws from loosening ?

[zombywoof]

4 hours ago, Rusl said:

Ok, today after around 300 rounds through the gun with the new optic mounted the screws came loose, I had blue locktite on them but I didn't de-grease the holes/screws before assembly so that may be the issue, I have degreased every thing and reassembled it, is there any thing else you guys are doing different to stop the mounting screws from loosening ?

I degrease, alcohol, acetone screws and threads. I use blue Loctite on the threads.  I then apply a small amount of Gorilla glue construction adhesive under the heads of the screws and the top portion of the screw. It helps bond the screws to the body of the optic not just relying on thread locker. This prevents the screws from moving and they release easily. 

 

 

[muncie21]

4 hours ago, Rusl said:

Ok, today after around 300 rounds through the gun with the new optic mounted the screws came loose, I had blue locktite on them but I didn't de-grease the holes/screws before assembly so that may be the issue, I have degreased every thing and reassembled it, is there any thing else you guys are doing different to stop the mounting screws from loosening ?

Definitely need to de-grease and use some form of thread locker as a minimum.

[Mauserlover]

Professor Atlas, I don't know if you still follow this thread, but if so, your threads have gotten me into a deep, dark hole with no escape. I am now looking to build a CZ-85B into an open gun (or at least work that way). 

 

I've spent too much time searching for this, obviously I'm doing it wrong. 

 

CZ hole patterns and Tanfoglio hole patterns are different, right? They are also different hole sizes and thread pitches, right? 

 

Where can I find the specs for these patterns? I've looked at C-More's site, Cajun, CZ Custom, etc. Anyone know what it is? I'm not spending $50 on a jig that I don't need when I have a milling machine. 

 

If nobody has the CZ pattern, does anyone have the Tanfoglio pattern? Thanks. 

[kneelingatlas]

The threads are M4X0.7 on both, but the patterns are different, I don't recall the spacing, but I'll look tonight.

[kneelingatlas]

Best I can tell they're 14.4mm on center, but you might want to get your mount and double check.

 

Edited February 18, 2020 by kneelingatlas

[Mauserlover]

Is that the normal CZ hole pattern? I'm guessing the Czechmate and TS would be some sort of standard for the folks who manufacture mounts, right? I might even make my own mount, rendering this conversation partly moot anyway. 

 

Thanks, the other information about the screws made my mind up about which taps to get! 

 

[kneelingatlas]

Czechmate and TSO have the same hole pattern, I'm not sure about the Champion.

[RonnieJr]

I used an EAA Witness(tangfo) mount and the hole spacing is 10mm on center and they are .330" down from the top edge of the dust cover of my Sp-01, which was the recommendation from Cajun Gun Works.  Good luck

[Ludde]

On 2/9/2020 at 11:40 PM, hawaiifivebro said:

 

Have you had a chance to test this out yet?

 

Now I've shot 3 full mags without any issues so far. Will be doing some minor tweaks to further improve the next test version.

[Ludde]

My first test of the gun after being modified. This is with minor PF N320 loads I had laying around.

 

This is also the first live fire test with the base pad prototype.

 

Ignore my sloppy recoil control, first time shooting in almost 6 months.

 

 

Next up load development and testing spring combos.

[Dan4147]

18 hours ago, Ludde said:

My first test of the gun after being modified. This is with minor PF N320 loads I had laying around.

 

This is also the first live fire test with the base pad prototype.

 

Ignore my sloppy recoil control, first time shooting in almost 6 months.

 

 

Next up load development and testing spring combos.

 

That brass...perfect.  I hope it does that with major.  You can use any dot mount you want!

[CZ75SP01Marc]

recoil looks nice, wonder how much difference there is shooting with comp or without with the minor load.

[Ludde]

5 hours ago, Dan4147 said:

 

That brass...perfect.  I hope it does that with major.  You can use any dot mount you want!

 

I hope so too, let's see how it goes. The test firing was with random mixed brass.

 

I plan on using the sebo weapons rearwards mounted sight mount.

[Ludde]

1 hour ago, CZ75SP01Marc said:

recoil looks nice, wonder how much difference there is shooting with comp or without with the minor load.

 

There is for sure a difference but I assume most of it is because of the added weight of the steel comp and cone thread adapter.

[mandaloin]

I'm looking to have a heavy "full profile" comp made for my SP-01, along the lines of these. Can anyone direct me to someone who would be willing to do the work? Haven't had any luck searching myself.

 

[kneelingatlas]

On 3/8/2020 at 3:00 PM, mandaloin said:

I'm looking to have a heavy "full profile" comp made for my SP-01, along the lines of these. Can anyone direct me to someone who would be willing to do the work? Haven't had any luck searching myself.

 

 

Scott Springer did that one, although I wasn't blown away.

[arkadi]

On 2/7/2020 at 10:04 AM, Rusl said:

That comp on the front of yours looks the part, is it custom made? I  assume you have fitted a threaded barrel. Never owned a gun with a comp I'm assuming you unscrew it each time to strip the slide off the gun or is there some other way around it?

 

The top gun is Binary Eng comp with custom steel conversion cone.

The bottom gun is a custom steel comp modeled after Binary Eng's comp with cone as one piece.

 

The barrel is original SP-01 barrel threaded 1/2" - 28.

 

I cannot remove barrel from slide as both comps are glued on. I clean it in place. CZ rarely needs cleaning.

[arkadi]

On 3/9/2020 at 12:00 AM, mandaloin said:

I'm looking to have a heavy "full profile" comp made for my SP-01, along the lines of these. Can anyone direct me to someone who would be willing to do the work? Haven't had any luck searching myself.

 

Are you searching for looks or function?

 

If looks are important, then making comp parallel to the slide on CZ is not trivial. It is not parallel on the photos you posted. IMO it would look as a chunk of metal out of place, in person. Also, it weight must be supported by something during recoil - either by cone or guide rod or both.

 

As for function, the best comps are compact and light. A light comp will work for major and minor.

 

 

[mandaloin]

 

3 hours ago, arkadi said:

 

The top gun is Binary Eng comp with custom steel conversion cone.

The bottom gun is a custom steel comp modeled after Binary Eng's comp with cone as one piece.

 

The barrel is original SP-01 barrel threaded 1/2" - 28.

 

I cannot remove barrel from slide as both comps are glued on. I clean it in place. CZ rarely needs cleaning.

 

I mostly want function but I do like the look of a full profile comp. From the sounds of it you're no longer able to remove your barrel from the slide at all? If so that's a dealbreaker for me.

 

I've noticed a lot of Glock guys just thread a comp on their barrel, tighten down a set screw, and call it a day. Is there a reason I don't see that with CZs?

Edited March 10, 2020 by mandaloin

[arkadi]

You could have a guide rod channel and barrel lug machined (for clearance), and a reverse plug installed, as per discussion somewhere above. Just never got to that point.

 

If I really-really need the barrel removed - due to a cracked comp for example - I use propane torch to kill Loctite and unscrew the comp. I also have a set screw in the cone.

 

Speculation: Glock guys who just tighten down a set screw never really shoot that much and/or they shoot plinking ammo. Until barrel thread and comp threads are matched exceptionally well, each shot will damage the threads.

 

I wouldn't look into Glock Open guns as an example to model my gunsmith practices on. There is a thread about Open Glocks here on BE. Anyway, I now have more Open 2011 than Open CZs.