Crosman Rear Sight CDPT1 Sloppy Threads

[Mike Carter]

Hello All,
Prior to the release of the Challenger 2021 our team purchased 4 Challenger 2009 rifles that were shipped with the new CDPT1 sight sets.
The difference between the older sight and the newer one being the ability to cant the sight, and the knob direction. The link below shows the sight I am referring too.
https://www.champchoice.com/mc-airgun/a ... set-cdpt1C

The amount of play in the rear diopter is enough to move the point of impact 3 scoring rings if it is bumped by or moved by the athlete, either with their head touching the blinder, or any other reason. Checking the run out with a dial indicator vertical and horizontal deflection is .030".
Why? The threads in the aluminum casting that moves when the spindles are turned are not tapped the complete length of the drilled hole. It appears they even made a clearance hole for the threaded spindle, which would have necessitated two machining operations.
In essence, there is not enough thread contact to eliminate the play between internal threads of the casting and the threads of the spindle. The only thing that keeps the rear diopter from moving is easily is the supplied sight blinder from Crosman that clips onto the rear diopter.

Has anyone else experienced this? And if so, have you developed a solution?
I tested the deflection in real time by wearing my precision shooting coat, ISSF Saur Sling and from the prone position at 10m on a Sius Hybrid score I could not form a consistent group in the 10 ring. I pressed the rear diopter to one side and took a shot and it was an 8 at 9:00. I pressed the other side, took a shot and it was a 9 at 3:00. Just for validation, I mounted a Walther rear sight from an LG300 and shot a ten shot string with a score of 99.
I realize mounting the Walther sight is illegal. I want to find a solution. I would also like to hear any feedback that has been provided by Crosman, aside from "What do you expect from a $150 rear sight" I know what I could expect from a $184 rear sight. Precision!!!https://www.champchoice.com/mc-optics-s ... ht-rig-590

In the end the Crosman Challenger with a Lothar Walther barrel is a very accurate air rifle, providing the rear sight could be made repeatable.
For the record I asked another coach who was visiting Champions Choice to check this deflection on a brand new sight out of the box. He said it had some deflection but not as much as what we had on ours. There should be no deflection on the rear sight as is on a precision rear sight.

If I were the product manager at Crosman I would evaluate the expense necessary to replace that aluminum casting with a steel billet with the threaded holes running the entire length of hole. I think the change in material would not adversely affect the cost of the rear sight while greatly improving the reliable repeatability on par with a precision rear sight.

Thanks for taking the time to read this and I hope a productive dialog will be the result.