The ZFK55 Scope

[Pierre]

First, unless you are very experienced in servicing Swiss Scopes........ do not attempt disassembly.
My visiting Father In Law is extremely experienced. One of the three who developed the world's first Atomic Microscope for Stanford University, R&D Head of Dept. for Jenkyl & Davidson, Head of R&D for Swift Instruments and a few other I don't remember........ he's qualified to do the job. This is what he discovered, and this applies to all zfk55 scopes.

All of them come with windage/elevation ball detents, however few of them can actually be felt when turning the knobs. Reason? Highly likely weak or broken springs under the single ball itself. A hole, the exact size of the ball and the spring is drilled into steel ring container. The spring is dropped in, the ball goes in on top of it and then the edge of the drilled hole is very gently and precisely "peened" with a circular tool of the correct diameter, trapping the ball just above diameter center.

There is, apparently, grease of a synthetic base in that ball detent hole as well as in the outer casing. The age may be the culprit for that spring to have weakened. Without that spring pressure, the ball simply either engages the detents very weakly or not at all. We're field testing on sent to us today. It did have a small screw floating in the windage housing, but that was only the reason for the reticle "jumping". The spring in this particular scope is either broken or extremely weak.

Having reassembled the turret, we found that there is very little resistance in the turret knob. We'll have two options to offer the owner later today. One, disassemble, remove the ball and spring, re-drill that hole 1/1000th larger, use a ball that's 1/1000th larger than the original and actually fabricate the required tool for "peening". Fortunately, my FIL is a machinist and more importantly, a micro-machinist. No ideas as of yet on the cost of doing this initial process, but both turrets would need to be done.

Second option: Add an extremely heavy grease, filling the inside of the turret to stabilize it an prevent the reticle from moving when the rifle is fired. We'll see about that one with field testing, so................

Don't get too bothered about your scope not registering either felt, or actual detent locking. You're all (including me) in the same boat

[Pierre]

and...... Standby. He's found a third option and he's dis-assembling again. LOL

[Pierre]

This is the rest of the running conversation from another forum.

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Seems that the manual says you can't hear or feel it. We can definitely feel it if you turn it slowly. That

"feel" will depend entirely on the depth of engagement by the ball. A bit confusing as the manual says

"no".

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Decision made 10 minutes ago by Grandpa. He is taking it back to the coast when he leaves. He needs his equipment and he'll be micro-machining a complete set of tools for working on these zfk55 scopes.

I'll let everyone concerned know when he's in a position to take care of your scopes. Be advised, he's nearly 91 years old and if he tires or it or is deluged with too many requests, there may be a time lag of a few months before he can supply Latigo with a complete set of tools and instruct him in detail as to the disassembly repair and reassembly of these scopes. It's not a simple process.

We have determined that Petrov's scope has indeed been disassembled and reassembled by someone who did no know what they were doing, and... we did find a small screew floating in the turret once again....... I reiterate that the windage detents can absolutely be felt, albeit lightly. The moa function in windage seems to be in the neighborhood of 1/8th moa. These other scopes are the norm, not the exception. I'll let you know about elevation later in the next few days. Petrov's must be disassembled and inspected anyway. That turret does seem to be different than the windage, but "how" has yet to be determined.

There may be an optics expert in your neck of the woods, but before you hand it over to him to "look and see", be damned sure of his qualifications.
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There is no ball and no spring in Petrov's elevation turret. There IS a place for them and there are detents, however, he noted that the slight "peening" required to retain the ball is not there and never has been. That leads him to believe that in the elevation system, they were not required as the turret is manufactured with built in "resistance" holding the elevation line tightly in place. Mine seem to be the same.

He intends to have a supply of the correct balls and springs on hand to install in the elevation turrets. I'd feel better "feeling" those detents as they are in my windage. That will be an option offered to any zfk55 mount owners that choose to do so.

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Now we know why the ball/spring is not necessary in the elevation turret........The Elevation turret has a very strong compression washer in it to hold it in adjustment. The hole is there and the detents are there, but no ball or spring. Today we're doing a test on the elevation turret. We're installing a ball and spring just to see how it works, but I can tell you that the compression washer is very strong, so there is no need for the ball and spring.

It's just interesting that is set up exactly like the windage. If you cannot actually feel the ball/detent clicks in your windage, then you definitely have a problem.
P

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The drilled hole for the ball is simply a pre-sizing hole. It's not the trued and finished size required for the ball. Because of that, the ball would not fit, so....... not required. The Tension Washer does the job.
P

[Miller Tyme]

+1, no ball & spring under my elevation turret, only on the windage turret.

[Pierre]

We'll be handling both zfk55 as well as the k31/43 scope repairs and renovations.
We now have the capabilities of Micro-Machining.
Both Edelweiss and Simpson's are our first customers.



P