Are CZs especially hard on Red Dot Sights?

[Motorcop]

Sometimes it is difficult figuring out what is "good" tight and what is too tight.  If you have to force the optic into the cutout I would think it could be too tight needing some clearance work.  I had a couple of Holoson optics and had a problem with one that had a misaligned outer grid image.  It drove me nuts and Holoson said it was normal.  I literally gave them away to my kid and went back to only using Trijicons in RMR or SRO variants.  My kid is happy because he didn't have to pay for the optics and I am happy to have gotten rid of foreign made optics.  I took a chance on Chi-Com stuff and knew better.  To recite my father, "What was I thinking?"

Rick H.

[MMH]

It could be that since it is so tight in the milled area, the forces are being transferred to the frame ends instead of the screw/pin locations where it was designed to be transmitted through.  This causes different harmonics and different internal forcing/bending that could be leading to failures

This does not make any sense to me.  The forces from the slide are not transmitted to the optic via frame ends.  The forces in the optic are from the mass of the optic and the acceleration that it sees as a result of the recoil and slide moving backward (i.e. F=ma).  The only way that screws would lessen this force is if the optic would move (in which case the acceleration would be slightly reduced resulting in a lower force being generated).  If the screws hold the optic firmly in place, the forces will be the same.  Personally, I would rather have a machined register rather than rely on screws getting loaded in shear.  Standard screws are NOT designed to take shear loads.  If this is their intended function than shoulder bolts should be used.

If the slide is improperly milled such that the optic is tight (i.e. wedged into the milled slide) than there are additional forces from the wedging action which could be harmful. is your slide that tight?

[Thauglor]

This does not make any sense to me.  The forces from the slide are not transmitted to the optic via frame ends.  The forces in the optic are from the mass of the optic and the acceleration that it sees as a result of the recoil and slide moving backward (i.e. F=ma).  The only way that screws would lessen this force is if the optic would move (in which case the acceleration would be slightly reduced resulting in a lower force being generated).  If the screws hold the optic firmly in place, the forces will be the same.  Personally, I would rather have a machined register rather than rely on screws getting loaded in shear.  Standard screws are NOT designed to take shear loads.  If this is their intended function than shoulder bolts should be used.

You didn't understand what I was writing or I didnt explain it well enough.  Yes the forces are the same, but if the part was designed to transmit the forces through the middle, then with a tight fitting slide now you are causing the edges to do it, the application is different than the design and could cause issues.  Especially so on anything that is designed to be as light as possible as these are, when you get lighter, off design points cause more issues. 

Changing the location of the force changes what parts are in tension/compression

If the slide is improperly milled such that the optic is tight (i.e. wedged into the milled slide) than there are additional forces from the wedging action which could be harmful. is your slide that tight?

This could add even more stress causing more failures, but it sounds like it is tight, without some FEA results, you will not be able to know what is tight or too tight

[Atomic Punk]

It could be that since it is so tight in the milled area, the forces are being transferred to the frame ends instead of the screw/pin locations where it was designed to be transmitted through.  This causes different harmonics and different internal forcing/bending that could be leading to failures

This does not make any sense to me.  The forces from the slide are not transmitted to the optic via frame ends.  The forces in the optic are from the mass of the optic and the acceleration that it sees as a result of the recoil and slide moving backward (i.e. F=ma).  The only way that screws would lessen this force is if the optic would move (in which case the acceleration would be slightly reduced resulting in a lower force being generated).  If the screws hold the optic firmly in place, the forces will be the same.  Personally, I would rather have a machined register rather than rely on screws getting loaded in shear.  Standard screws are NOT designed to take shear loads.  If this is their intended function than shoulder bolts should be used.

If the slide is improperly milled such that the optic is tight (i.e. wedged into the milled slide) than there are additional forces from the wedging action which could be harmful. is your slide that tight?

The RDS does not need to be forced into place. It is more like wiggle it side to side and lightly push at an angle to get it into just the right position for it to drop into place.

I just broke a 6 month old slide stop yesterday so I am going up to a 14lb recoil spring.

 

[MMH]

This does not make any sense to me.  The forces from the slide are not transmitted to the optic via frame ends.  The forces in the optic are from the mass of the optic and the acceleration that it sees as a result of the recoil and slide moving backward (i.e. F=ma).  The only way that screws would lessen this force is if the optic would move (in which case the acceleration would be slightly reduced resulting in a lower force being generated).  If the screws hold the optic firmly in place, the forces will be the same.  Personally, I would rather have a machined register rather than rely on screws getting loaded in shear.  Standard screws are NOT designed to take shear loads.  If this is their intended function than shoulder bolts should be used.

You didn't understand what I was writing or I didnt explain it well enough.  Yes the forces are the same, but if the part was designed to transmit the forces through the middle, then with a tight fitting slide now you are causing the edges to do it, the application is different than the design and could cause issues.  Especially so on anything that is designed to be as light as possible as these are, when you get lighter, off design points cause more issues. 

Changing the location of the force changes what parts are in tension/compression

If the slide is improperly milled such that the optic is tight (i.e. wedged into the milled slide) than there are additional forces from the wedging action which could be harmful. is your slide that tight?

This could add even more stress causing more failures, but it sounds like it is tight, without some FEA results, you will not be able to know what is tight or too tight

You are overthinking this.  If it is tight and wedging, then that can cause a failure.  I don't need an FEA analysis to prove that I can split a piece of wood with a wedge. 

The answer is simple.  Mill the slide to assure that you have some clearance. Bolts can exert tremendous clamping force.  If there is insufficient clearance to the edge, then instead of exerting this clamping force to secure the bottom of the optic to the slide, there will be a moment (i.e. a twisting force) from the center of the bolt hole location of the optic to the edge that 'is too tight'.  This will flex (via tensile forces in the bottom and compressive forces on the top) the optic base.  In addition these forces will distort the housing in other unpredictable ways, possibly breaking electronic connections (depending how the PCB board is designed, fits/mounts in the housing etc). 

[gunbuster]

Want to add a green dot instead of red to a CZ SP01 or Phantom. Has anyone tried green dots? Willing to get a trijicon but seems harder to get the parts. Suggestions appreciated. Thank you.

[RSR]

Want to add a green dot instead of red to a CZ SP01 or Phantom. Has anyone tried green dots? Willing to get a trijicon but seems harder to get the parts. Suggestions appreciated. Thank you.

Green work the same as red -- the question is whether wherever you're shooting has a lot of greenery that makes for less of a contrast for a green dot than a red one.

[Wobbly]

I just broke a 6 month old slide stop yesterday so I am going up to a 14lb recoil spring.

This is from the OP !

So, your gun busted a slide stop and keeps breaking optics? I'd say your recoil springing* isn't stout enough (either too low of a spring rating OR simply worn out OR completely wrong spring) for the energy in the cartridges you are shooting.

* Remember on recoil, the recoil spring AND the hammer spring work together to slow and cushion the rearward travel of the slide. One or both of those springs needs replacing, or you need some different ammo.

In my experience, your brass should be traveling 4 to 8 feet upon ejection. The acceleration of the slide as it travels rearward directly impinges upon the case during ejection. Thus, the ejection distance is directly proportional to the energy in the slide, which of course is 100% directly related to the ammunition you are shooting.

[MMH]

* Remember on recoil, the recoil spring AND the hammer spring work together to slow and cushion the rearward travel of the slide. One or both of those springs needs replacing, or you need some different ammo.

In my experience, your brass should be traveling 4 to 8 feet upon ejection. The acceleration of the slide as it travels rearward directly impinges upon the case during ejection. Thus, the ejection distance is directly proportional to the energy in the slide, which of course is 100% directly related to the ammunition you are shooting.

So 4 to 8 feet is a good distance for a P-01?  Mine ejects the brass further than that - probably 12 feet or so.  Standard ball ammo, stock P-01 around 1000 rounds.  Functions great so I am not inclined to change springs or anything else.  On the other hand, I do not want to beet my gun up if my springs are too weak.

I used to have a HK P7 that would toss the brass 30 to 40 feet - no exaggeration.  Was a great gun and SUPER reliable.  Put many thousands of rounds through it but saving your brass was impossible.

[RSR]

* Remember on recoil, the recoil spring AND the hammer spring work together to slow and cushion the rearward travel of the slide. One or both of those springs needs replacing, or you need some different ammo.

In my experience, your brass should be traveling 4 to 8 feet upon ejection. The acceleration of the slide as it travels rearward directly impinges upon the case during ejection. Thus, the ejection distance is directly proportional to the energy in the slide, which of course is 100% directly related to the ammunition you are shooting.

So 4 to 8 feet is a good distance for a P-01?  Mine ejects the brass further than that - probably 12 feet or so.  Standard ball ammo, stock P-01 around 1000 rounds.  Functions great so I am not inclined to change springs or anything else.  On the other hand, I do not want to beet my gun up if my springs are too weak.

I used to have a HK P7 that would toss the brass 30 to 40 feet - no exaggeration.  Was a great gun and SUPER reliable.  Put many thousands of rounds through it but saving your brass was impossible.

Is your gun factory sprung or altered?  If factory, you're good to go, provided changing recoil spring at least every 5k rounds.  Factory setup is milspec and intended to work across a wide range of rounds/loadings.

IIRC, Admin Wobbly is a reloader and don't know offhand to what extent he tunes his guns and/or uses them in competition, but all are a whole other ballgame from a standard "factory-spec" gun and ammo shooter...  However, if you're exclusively shooting hot NATO-spec 9mm ball and/or+P 9mm self-defense ammo then you *might* want to test upping your recoil spring weight a level or two for ~500 rounds to ensure reliability and protect the alloy frame -- but if not, I'd suggest leaving it alone.

[Wobbly]

So 4 to 8 feet is a good distance for a P-01?  Mine ejects the brass further than that - probably 12 feet or so.  Standard ball ammo, stock P-01 around 1000 rounds.  Functions great so I am not inclined to change springs or anything else.  On the other hand, I do not want to beet my gun up if my springs are too weak.

What is the weight of the bullet weight and velocity of this "standard ball" ammo ? Is this standard set by NATO or Walmart ?

You might expect 12 feet from European made 115gr. If I was getting 12 feet from Winchester 115gr "white box" or Remington UMC then I might investigate.

How far are they thrown when using 124 or 147gr ?

I used to have a HK P7 that would toss the brass 30 to 40 feet - no exaggeration.  Was a great gun and SUPER reliable.  Put many thousands of rounds through it but saving your brass was impossible.

Different gun designs use different parts of the frame and internal works to stop the slide. I can't discuss the HK design because I don't know. But 30 to 40 feet would seem to indicate an excessive amount of energy being imparted to the cases.

[Wobbly]

RSR and I were posting at the same time. But we basically agree... with different caveats.

"For every action, there is an opposite but equal reaction." The operation of the slide is the "reaction". Some hot 115gr might get you to 12 feet. Try some 124gr.

[MMH]

So 4 to 8 feet is a good distance for a P-01?  Mine ejects the brass further than that - probably 12 feet or so.  Standard ball ammo, stock P-01 around 1000 rounds.  Functions great so I am not inclined to change springs or anything else.  On the other hand, I do not want to beet my gun up if my springs are too weak.

What is the weight of the bullet weight and velocity of this "standard ball" ammo ? Is this standard set by NATO or Walmart ?

You might expect 12 feet from European made 115gr. If I was getting 12 feet from Winchester 115gr "white box" or Remington UMC then I might investigate.

How far are they thrown when using 124 or 147gr ?

I will have to start collecting more detailed data.  Also, have somebody watch to see how far the case is tossed.  It may be bouncing on the range floor and skidding further away than it is ejected.

I used to have a HK P7 that would toss the brass 30 to 40 feet - no exaggeration.  Was a great gun and SUPER reliable.  Put many thousands of rounds through it but saving your brass was impossible.

Different gun designs use different parts of the frame and internal works to stop the slide. I can't discuss the HK design because I don't know. But 30 to 40 feet would seem to indicate an excessive amount of energy being imparted to the cases.

Agreed.  The P7 was essentially a blow back design w/ a retarding gas piston.  A truly unique design.  Also had a fluted chamber to assist in extraction.  Hot loads would fire form in the chamber and the case would not be reloadable.  The gun was designed w/ ultimate reliability in mind.  excessive energy imparted to the case just a side effect.  Reminded me how hard a MP5 would eject a case.